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Sun of Goddard Space Flight Center (GSFC) from 1999
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Hubble Picture Adds to Plane
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| Title |
Hubble Picture Adds to Planet-Making Recipe |
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Hubble Telescope Reveals Swa
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| Title |
Hubble Telescope Reveals Swarm of Glittering Stars in Nearby Galaxy |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ] |
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Dying Star Sculpts Rungs of
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| Title |
Dying Star Sculpts Rungs of Gas and Dust |
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Polar Visible Aurora: Low So
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| Title |
Polar Visible Aurora: Low Solar Wind Conditions on May 11, 1999 over the North Pole |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar: PIXIE at Apogee on Ma
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| Title |
Polar: PIXIE at Apogee on May 11, 1999 (North) |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Aurora over the North Pole o
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| Title |
Aurora over the North Pole on April 17, 1999 (WMS) |
| Abstract |
When the charged particles flowing outward from the Sun (the solar wind) hit the Earth's magnetic field, they are channeled down the magnetic field lines to the ionosphere at the North and South Poles. The impact of these particles on atmospheric molecules causes the molecules to emit light, which forms the visible aurora. This visualization shows the development of the aurora over the North Pole for about three hours on April 17, 1999, as seen by the ultraviolet VIS Earth Camera on the POLAR spacecraft. The two main features of these ultraviolet images are the very bright ultraviolet emission from the reflected solar radiation on the dayside of the Earth and the bright ring of the auroral oval circling the North Pole. The aurora seen in this visualization is the diffuse aurora, a very large bright band that is actually too dim to be seen well from the ground by the human eye. What we normally think of as the aurora are the even brighter curtains of light within the diffuse auroral caused by very energetic electrons. These curtains are too small to be seen in this image. The diffuse aurora appears as a ring around the pole rather than as a bright spot over the entire pole because the solar particles actually spend extended time wandering about within the Earth's magnetic field before traveling down a very select set of magnetic field lines to the Earth. Near the end of this three hour period, the spacecraft was getting so close to the Earth that the edges of the globe were outside the camera's image, which accounts for the growing circular data gaps over Asia and the Pacific Ocean. |
| Completed |
2004-07-09 |
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Aurora over the North Pole o
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| Title |
Aurora over the North Pole on April 17, 1999 (WMS) |
| Abstract |
When the charged particles flowing outward from the Sun (the solar wind) hit the Earth's magnetic field, they are channeled down the magnetic field lines to the ionosphere at the North and South Poles. The impact of these particles on atmospheric molecules causes the molecules to emit light, which forms the visible aurora. This visualization shows the development of the aurora over the North Pole for about three hours on April 17, 1999, as seen by the ultraviolet VIS Earth Camera on the POLAR spacecraft. The two main features of these ultraviolet images are the very bright ultraviolet emission from the reflected solar radiation on the dayside of the Earth and the bright ring of the auroral oval circling the North Pole. The aurora seen in this visualization is the diffuse aurora, a very large bright band that is actually too dim to be seen well from the ground by the human eye. What we normally think of as the aurora are the even brighter curtains of light within the diffuse auroral caused by very energetic electrons. These curtains are too small to be seen in this image. The diffuse aurora appears as a ring around the pole rather than as a bright spot over the entire pole because the solar particles actually spend extended time wandering about within the Earth's magnetic field before traveling down a very select set of magnetic field lines to the Earth. Near the end of this three hour period, the spacecraft was getting so close to the Earth that the edges of the globe were outside the camera's image, which accounts for the growing circular data gaps over Asia and the Pacific Ocean. |
| Completed |
2004-07-09 |
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Polar: PIXIE at Perigee 1 on
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| Title |
Polar: PIXIE at Perigee 1 on May 11, 1999 (South) |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar: PIXIE at T055798 on M
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| Title |
Polar: PIXIE at T055798 on May 11, 1999 at 05:05 |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar: PIXIE at T055798 on M
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| Title |
Polar: PIXIE at T055798 on May 11, 1999 at 22:55 |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar: PIXIE at Perigee 2 on
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| Title |
Polar: PIXIE at Perigee 2 on May 11, 1999 (South) |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar Visible Aurora: North
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| Title |
Polar Visible Aurora: North Pole Comparison between May 11, 1999 and November 13, 1999 (Grid) |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar Visible Aurora: Low So
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| Title |
Polar Visible Aurora: Low Solar Wind Conditions on May 11, 1999 over the South Pole |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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Polar Visible Aurora: North
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| Title |
Polar Visible Aurora: North Pole Comparison between May 11, 1999 and November 13, 1999 (Continents) |
| Abstract |
On May 11, 1999, the solar wind that blows constantly from the Sun virtually disappeared. Dropping to a small fraction of its normal density and to half its normal speed, the solar wind died down enough to allow physicists to observe particles flowing directly from the Sun's corona to Earth. This severe change in the solar wind also drastically changed the shape of Earth's magnetic field and produced a rare auroral display at Earth's North Pole. |
| Completed |
1999-12-08 |
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A Solar Prominence from SOHO
| Title |
A Solar Prominence from SOHO |
| Explanation |
How can gas float above the Sun? Twisted magnetic [ http://antwrp.gsfc.nasa.gov/apod/ap971106.html ] fields arching from the solar surface can [ http://hesperia.gsfc.nasa.gov/~knisely/course_development.html ] trap ionized gas, suspending it in huge looping structures. These majestic plasma arches [ http://antwrp.gsfc.nasa.gov/apod/ap970918.html ] are seen as prominences above the solar limb. In September 1999, this dramatic and detailed image was recorded by the EIT experiment on board the space-based SOHO observatory [ http://seal.nascom.nasa.gov/explore/ ] in the light emitted by ionized Helium [ http://antwrp.gsfc.nasa.gov/apod/ap960520.html ]. It shows hot plasma escaping into space as a fiery prominence breaks free from magnetic confinement [ http://www.lmsal.com/solarsites.html ] a hundred thousand kilometers above the Sun. These awesome events [ http://antwrp.gsfc.nasa.gov/apod/ap970127.html ] bear watching [ http://umbra.nascom.nasa.gov/ ] as they can affect communications and power systems over 100 million kilometers [ http://antwrp.gsfc.nasa.gov/apod/ap981212.html ] away on Planet Earth [ http://antwrp.gsfc.nasa.gov/apod/ap050102.html ]. |
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LP 944-20: A Failed Star Fla
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| Title |
LP 944-20: A Failed Star Flares |
| Explanation |
The tiny spot circled on the right actually represents a big astronomical discovery [ http://chandra.harvard.edu/press/00_releases/ press_071100.html ] -- the first detected flare from a failed star. Failed stars, termed brown dwarfs [ http://chandra.harvard.edu/xray_sources/ browndwarf_fg.html ] in astronomers' parlance [ http://oposite.stsci.edu/pubinfo/background-text/ brdwarfs.txt ], are too low in mass to ignite nuclear hydrogen burning in their cores, yet still shine feebly as the energy from their gravitational collapse is converted to heat and light. In fact, the dim brown dwarf [ http://www.amsci.org/amsci/articles/97articles/ martin.html ] cataloged as LP944-20 is estimated to have only 6 percent the mass of the Sun (60 times the mass of Jupiter) and one-tenth the Sun's diameter. A mere 16 light-years distant in the southern constellation Fornax it is well studied [ http://www.eso.org/outreach/press-rel/pr-1997/ pr-07-97.html ], but this failed star recently startled astronomers [ http://xxx.lanl.gov/abs/astro-ph/0005559 ] by producing a flare visible at x-ray energies [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/ history1_xray.html ]. The above Chandra X-ray Observatory [ http://chandra.harvard.edu/ ] images of the LP944-20 [ http://chandra.harvard.edu/photo/cycle1/1054/ lp94420_hand.html ] star field were recorded in December 1999. Showing nothing (left) for the first nine hours, the brown dwarf generated a significant x-ray flare during the final hours of the observation. How did a failed star produced such a high-energy flare [ http://antwrp.gsfc.nasa.gov/apod/ap000608.html ]? Magnetic fields twisted and broken by turbulent motions near the surface of the brown dwarf may be the culprit. Difficult [ http://antwrp.gsfc.nasa.gov/apod/ap990324.html ] to detect because they are otherwise faint, brown dwarf stars are believed to be common [ http://www.amsci.org/amsci/articles/97articles/ mhowmany.html ] throughout the galaxy. |
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The Big Corona
| Title |
The Big Corona |
| Explanation |
Most photographs don't adequately portray the magnificence of the Sun [ http://www.nineplanets.org/sol.html ]'s corona. Seeing the corona [ http://www.lmsal.com/YPOP/Spotlight/Tour/corona2.html ] first-hand during a total solar eclipse [ http://www.mreclipse.com/TSE99reports/TSE99reports.html ] is best. The human eye [ http://www.orlions.org/eyetour/eyetourhome.html ] can adapt to see features and extent that photographic film [ http://web.islandnet.com/~yesmag/how_work/film.html ] usually cannot. Welcome, however, to the digital [ http://gcc.bradley.edu/exhibit/98/home.html ] age. The above picture [ http://www.mreclipse.com/TSE99reports/TSE99Espenak.html ] is a combination of twenty-two photographs that were digitally processed to highlight faint features of a total eclipe that occurred in August of 1999. The outer pictures of the Sun's corona [ http://www.windows.umich.edu/cgi-bin/tour.cgi?link=/sun/atmosphere/corona.html ] were digitally altered to enhance dim, outlying waves and filaments. The inner pictures of the usually dark Moon [ http://antwrp.gsfc.nasa.gov/apod/moon.html ] were enhanced to bring out its faint glow from doubly reflected sunlight [ http://antwrp.gsfc.nasa.gov/apod/ap960530.html ]. Shadow seekers [ http://sunearth.gsfc.nasa.gov/eclipse/eclipse.html ] need not fret, though, since as yet there is no way that digital image processing can mimic the fun [ http://antwrp.gsfc.nasa.gov/apod/ap990902.html ] involved in experiencing a total solar eclipse [ http://www.mreclipse.com/TSE99reports/TSE99Rao.html ]. The next total solar eclipse [ http://sunearth.gsfc.nasa.gov/eclipse/TSE2001/TSE2001.html ] will be visible from parts of Africa on June 21. |
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Analemma over Ukraine
| Title |
Analemma over Ukraine |
| Explanation |
If you took a picture of the Sun at the same time each day, would it remain in the same position? The answer is no, and the shape traced out by the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap000621.html ] over the course of a year is called an analemma [ http://www.uwm.edu/~kahl/Images/Weather/Other/analemma.html ]. The Sun's apparent shift is caused by the Earth's motion [ http://zebu.uoregon.edu/~soper/Orbits/earthorbit.html ] around the Sun when combined with the tilt of the Earth's [ http://www.windows.ucar.edu/tour/link=/the_universe/uts/earth2.html ] rotation axis. The Sun will appear at its highest point of the analemma [ http://solar-center.stanford.edu/FAQ/Qsunaspattern.html ] during summer [ http://antwrp.gsfc.nasa.gov/apod/ap001223.html ] and at its lowest during winter. Analemmas [ http://www.jgiesen.de/analemma/ ] created from different Earth latitudes [ http://en.wikipedia.org/wiki/Latitude ] would appear at least slightly different, as well as analemmas [ http://en.wikipedia.org/wiki/Analemma ] created at a different time each day. The analemma [ http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search?analemma ] pictured to the left [ http://vrum.chat.ru/Photo/Astro/analema.htm ] was built up by Sun photographs [ http://antwrp.gsfc.nasa.gov/apod/ap980526.html ] taken from 1998 August through 1999 August from Ukraine [ http://www.cia.gov/cia/publications/factbook/geos/up.html ]. The foreground picture [ http://www.digg.com/space/Pic_The_Path_Taken_By_The_Sun_Spread_Out_Over_A_Year ] from the same location was taken during the early evening in 1999 July. |
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Diamond Ring in the Sun
| Title |
Diamond Ring in the Sun |
| Explanation |
Today, earthbound skygazers can celebrate a solstice [ http://www-spof.gsfc.nasa.gov/stargaze/Sseason.htm ], a new Moon [ http://aa.usno.navy.mil/faq/docs/moon_phases.html ], the closest approach [ http://mars.jpl.nasa.gov/ ] of planet Mars since 1988 ... oh yes, and a total eclipse of the Sun, the first total solar eclipse [ http://sunearth.gsfc.nasa.gov/eclipse/TSE2001/TSE2001.html ] of the third millennium. Of course for some, today's most spectacular celestial views will be of the eclipsed Sun [ http://science.nasa.gov/headlines/y2001/ast19jun_1.htm ] from along the path of totality as the new Moon's shadow tracks across southern Africa and Madagascar [ http://www.madagascar-eclipse2001.com/eclipse_.htm ]. This picture from the August 1999 total solar eclipse captures the shimmering solar corona just as that eclipse's total phase ended, as seen from eastern Turkey. The first rays of bright sunlight shinning through edge-on [ http://sunearth.gsfc.nasa.gov/eclipse/TSE2001/TSE2001fig/ TSE2001fig08.GIF ] lunar mountains and valleys create the fleeting appearance of glistening diamonds set in a ring around the Moon's silhouette. Do you want to see today's solar eclipse? Eclipse expeditions are offering live webcasts [ http://www.bit-net.com/~pauer/eclipse01/ ]. |
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Total Eclipse of the Active
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| Title |
Total Eclipse of the Active Sun |
| Explanation |
A total eclipse of the Sun [ http://www.mreclipse.com/Special/SEprimer.html ] is that special geocentric celestial event [ http://www.earthview.com/tutorial/causes.htm ] where the Moon passes exactly in front of the solar disk. During a fleeting [ http://antwrp.gsfc.nasa.gov/apod/ap970827.html ] few minutes of totality, fortunate earthdwellers located within the path of the Moon's dark shadow can witness [ http://www.earthview.com/tutorial/effects.htm ] the wondrous shimmering solar corona [ http://antwrp.gsfc.nasa.gov/apod/ap010408.html ] sharing the sky with stars and bright planets. The next total solar eclipse will occur tomorrow, June 21 [ http://sunearth.gsfc.nasa.gov/eclipse/TSE2001/ TSE2001.html ]. Since the Sun is still near the maximum [ http://antwrp.gsfc.nasa.gov/apod/ap010301.html ] of its 11 year activity cycle, careful [ http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/safety.html ] eclipse-watchers will also likely see the spectacle of bright solar prominences lofted above active regions around the Sun's edge. In fact, a telescopic view could be similar to this stunningly detailed image -- a picture of the solar eclipse of August 1999 taken at the beginning of totality from Kecel, Hungary. The upcoming 2001 June 21 event [ http://www.skypub.com/sights/eclipses/solar/ 0009africapreview.html ] will be visible as a partial eclipse from some of South America and much of Africa, but will only be total along a 125 mile wide path that tracks across land [ http://sunearth.gsfc.nasa.gov/eclipse/TSE2001/ T01animate.html ] through Southern Africa and Madagascar. Of course, if you can't travel to Africa tomorrow [ http://science.nasa.gov/headlines/y2001/ast19jun_1.htm ] (and you're not already there), web sites plan [ http://www.bit-net.com/~pauer/eclipse01/ ] to offer live views from the Moon's shadow [ http://antwrp.gsfc.nasa.gov/apod/ap980312.html ]! |
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Pluto: The Frozen Planet
| Title |
Pluto: The Frozen Planet |
| Explanation |
The Hubble Space Telescope imaged [ http://www.ast.cam.ac.uk/HST/press/pluto.html ] Pluto and its moon Charon in 1994. Pluto [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/pluto.html ] is usually the most distant planet from the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap950813.html ] but because of its elliptic orbit Pluto crossed inside of Neptune [ http://antwrp.gsfc.nasa.gov/apod/ap950817.html ]'s orbit in 1979 and will cross back out again in 1999. Compared to the other planets, very little is known about Pluto. Pluto [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/pluto.html ] is smaller than any other planet and even smaller than several other planet's moons. From Pluto, the Sun is just a tiny point of light. Pluto [ http://dosxx.colorado.edu/plutohome.html ] is probably composed of frozen rock and ice, much like Neptune's moon Triton [ http://antwrp.gsfc.nasa.gov/apod/ap950805.html ]. Pluto has not yet been visited by a spacecraft, but a mission [ http://www.jpl.nasa.gov/pluto/ ] is being planned for the next decade. Tomorrow's picture: Our Solar System from Voyager |
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Analemma
| Title |
Analemma |
| Explanation |
If you took a picture of the Sun at the same time each day, would it remain in the same position? The answer is no, and the shape traced out by the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap000621.html ] over the course of a year is called an analemma [ http://www.uwm.edu/~kahl/Images/Weather/Other/analemma.html ]. The Sun's apparent shift is caused by the Earth's motion [ http://zebu.uoregon.edu/~soper/Orbits/earthorbit.html ] around the Sun when combined with the tilt of the Earth's [ http://www.crh.noaa.gov/fsd/astro/season.htm ] rotation axis. The Sun will appear at its highest point of the analemma [ http://solar-center.stanford.edu/FAQ/Qsunaspattern.html ] during summer [ http://antwrp.gsfc.nasa.gov/apod/ap001223.html ] and at its lowest during winter. Analemmas [ http://www.jgiesen.de/analemma/ ] created from different Earth latitudes [ http://www.cogtech.com/EXPLORER/lat-long.htm ] would appear at least slightly different, as well as analemmas [ http://www.wshs.fcps.k12.va.us/vault/svanbroc/analemma.htm ] created at a different time each day. The analemma [ http://www.finseth.com/~fin/Java/Analemma0.html ] pictured to the left [ http://vrum.chat.ru/Photo/Astro/analema.htm ] was built up by Sun photographs [ http://www.shadow.net/~bobt/office/office.htm ] taken from 1998 August through 1999 August from Ukraine [ http://www.cia.gov/cia/publications/factbook/geos/up.html ]. The foreground picture from the same location was taken during the early evening in 1999 July. |
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NEAR Mathilde
| Title |
NEAR Mathilde |
| Explanation |
Hey Earth, look what I found! On the way to visiting the asteroid [ http://hurlbut.jhuapl.edu/NEAR/Education/intro/minorobjects.html ] 433 Eros in February 1999, the Near Earth Asteroid Rendezvous [ http://sd-www.jhuapl.edu/NEAR/Education/NEARcurrlynx.html ] (NEAR) spacecraft flew right by another asteroid: 253 Mathilde [ http://hurlbut.jhuapl.edu/NEAR/Education/intro/mathilde.html ] last Friday. Shown above [ http://sd-www.jhuapl.edu/NEAR/Mathilde/images.html ] is one picture from the encounter. Mathilde is a large chunk of rock [ http://www.seds.org/nineplanets/nineplanets/asteroids.html ] roughly 60 kilometers across that orbits the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap960518.html ] between Mars [ http://antwrp.gsfc.nasa.gov/apod/ap970627.html ] and Jupiter [ http://www.seds.org/nineplanets/nineplanets/jupiter.html ] in the main asteroid belt [ http://ispec.ucsd.edu/student-pages/asteroids/ ]. Mathilde's surface is very dark and heavily cratered. The NEAR pictures of Mathilde [ http://sd-www.jhuapl.edu/NEAR/Mathilde/images.html ] received so far indicate that the asteroid has undergone spectacular collisions, one of which created the huge impact basin in the center, which is estimated to be about 10 kilometers deep. |
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A Planet Transits the Sun
| Title |
A Planet Transits the Sun |
| Explanation |
Today an astronomical event will occur that no living person has ever seen: Venus will cross [ http://sunearth.gsfc.nasa.gov/sunearthday/2004/vt_edu2004_venus_back_his.htm ] directly in front of the Sun. A Venus crossing [ http://sunearth.gsfc.nasa.gov/sunearthday/2004/index_vthome.htm ], called a transit, last occurred in 1882 and was front-page [ http://image.gsfc.nasa.gov/poetry/venus/News/NYT12071882.pdf ] news [ http://image.gsfc.nasa.gov/poetry/venus/News/News.html ] around the world. Today's transit will be visible [ http://skyandtelescope.com/observing/objects/planets/article_1021_1.asp ] in its entirety throughout Europe and most of Asia and Africa. The northeastern half of North America [ http://science.nasa.gov/headlines/y2004/02jun_viewersguide.htm ] will see the Sun rise with the dark dot of Venus [ http://www.saao.ac.za/~wpk/tov1882/tovwell.html ] already superposed. Never look directly at the Sun [ http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/safety.html ], even when Venus is in front [ http://image.gsfc.nasa.gov/poetry/venus/TransitFAQs.html ]. Mercury's closer proximity to the Sun cause it to transit every few years. In fact, the above image mosaic of Mercury crossing the Sun [ http://www.space.com/scienceastronomy/venus_transit_2004.html ] is from two [ http://antwrp.gsfc.nasa.gov/apod/ap991119.html ] transits [ http://antwrp.gsfc.nasa.gov/apod/ap991210.html ] ago [ http://antwrp.gsfc.nasa.gov/apod/ap030513.html ], in November 1999. Will anyone living see the next Venus transit [ http://www.astronomy.com/content/dynamic/articles/000/000/001/745fvezh.asp ]? Surely yes since it occurs in 2012. |
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Bright Comet SOHO
| Title |
Bright Comet SOHO |
| Explanation |
Discovered this month [ http://antwrp.gsfc.nasa.gov/apod/ap980520.html ] with an orbiting solar observatory, bright Comet SOHO [ http://encke.jpl.nasa.gov/index.html ] has now emerged from the Sun's glare. This telephoto picture of the new naked-eye comet [ http://www.ozemail.com.au/~mhorn/soho.html ] was taken by astrophotographer Michael Horn [ http://www.ozemail.com.au/~mhorn/photos.html ] after sunset in the western twilight above Lake Samsonvale, Brisbane, Australia on May 18. The comet is seen [ http://www.astro.uio.no/~bgranslo/soho.html ] in the constellation Orion [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Orion.html ]. Its long lovely tail [ http://antwrp.gsfc.nasa.gov/apod/ap960502.html ] stretches nearly 5 degrees to the bright star Bellatrix [ http://www.astro.wisc.edu/~dolan/constellations/hr/1790.html ], near the top of the image. For Southern Hemisphere comet watchers, views of Comet SOHO (1998J1) will improve as this month draws to a close and the comet climbs to the south and east on its journey outward bound. In February 1999, NASA plans to launch the Stardust mission [ http://stardust.jpl.nasa.gov/top.html ] to fly close to a comet [ http://stardust.jpl.nasa.gov/news/ ] and return samples of dust from a comet's tail [ http://stardust.jpl.nasa.gov/comets/wild2.html ]. |
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Follow The Spots
| Title |
Follow The Spots |
| Explanation |
The Sun rotates [ http://wwwssl.msfc.nasa.gov/ssl/pad/solar/sunturn.htm ] on its axis about once every 27 days. How can you tell? Just follow the sunspots [ http://louis.lmsal.com/PR/science/exercise-1.html ]. This composite picture was constructed from solar images recorded daily by the MDI instrument [ http://soi.stanford.edu/science/obs_prog.html ] on board the space-based SOlar and Heliospheric Observatory [ http://sohowww.nascom.nasa.gov/descriptions/mission/english/ ] (SOHO). It shows the Sun's [ http://antwrp.gsfc.nasa.gov/htmltest/gifcity/interv.html ] visible surface for most days of August 1999 so that the same sunspots appear many times as the solar rotation carries them across the face of the Sun [ http://solar-center.stanford.edu/folklore/folklore.html ]. Sunspot [ http://es.rice.edu/ES/humsoc/Galileo/Things/sunspots.html ] temperatures are around 5,000 degrees C. but the spots appear dark as they are actually cooler than the surrounding regions of the solar surface. The sequential images of the sunspot groups [ http://antwrp.gsfc.nasa.gov/apod/ap980322.html ] show how these regions with high magnetic fields change from day to day. |
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A Leonids Meteor Storm in 19
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| Title |
A Leonids Meteor Storm in 1999 |
| Explanation |
The 1999 Leonids meteor shower [ http://www.skypub.com/sights/meteors/leonids/9911leo.html ] was not equally good for everybody. Only observers in Europe [ http://www.eso.org/outreach/info-events/leonids99/ ] and the Middle East with clear skies near 2 am (UTC) on 1999 November 18 saw rates shoot up to a meteor every few seconds. Above [ http://www.skylook.net/ ], however, is a picture taken from Spain during this time, with over a dozen faint meteors visible as green streaks [ http://antwrp.gsfc.nasa.gov/apod/ap981120.html ] eminating from Leo [ http://antwrp.gsfc.nasa.gov/apod/ap981208.html ] during just a six minute exposure. Although more numerous, the 1999 Leonids [ http://www.imo.net/leo99/leo99index.html ] did not have the same high proportion of bright meteors and fireballs as the 1998 Leonids [ http://antwrp.gsfc.nasa.gov/apod/ap981119.html ]. Last year's Leonid fireballs [ http://antwrp.gsfc.nasa.gov/apod/ap991112.html ] have been traced back [ http://www.arm.ac.uk/leonid/leopress.html ] to the 1333 passage of Comet Tempel-Tuttle [ http://www.lowell.edu/users/farnham/tt/tthist.html ]. The orbit of Jupiter [ http://www.seds.org/nineplanets/nineplanets/jupiter.html ] continually deflected one stream of cast-off particles while the smallest meteors [ http://leonids.hq.nasa.gov/ ] in this stream were removed by light pressure [ http://www.esc.cam.ac.uk/Library/Journals/J.Conf.Abs./1/222.html ] from the Sun. The remaining Leonids [ http://leonidslive.com ] were relatively large, pea [ http://www.umext.maine.edu/onlinepubs/htmpubs/4256.htm ] sized or larger, compared to the sand [ http://www.paccd.cc.ca.us/instadmn/physcidv/geol_dp/dndougla/SAND/SANDHP.htm ]-sized Leonids that are more common. |
|
Ant nebula
| Title |
Ant nebula |
| Description |
A new Hubble Space Telescope image of a celestial object called the Ant Nebula may shed new light on the future demise of our Sun. The image is available at http://www.jpl.nasa.gov/pictures/wfpc . The nebula, imaged on July 20, 1997, and June 30, 1998, by Hubble's Wide Field and Planetary Camera 2, was observed by Drs. Raghvendra Sahai and John Trauger of NASA's Jet Propulsion Laboratory, Pasadena, Calif., Bruce Balick of the University of Washington in Seattle, and Vincent Icke of Leiden University in the Netherlands. JPL designed and built the camera. The Ant Nebula, whose technical name is Mz3, resembles the head and thorax of an ant when observed with ground-based telescopes. The new Hubble image, with 10 times the resolution revealing 100 times more detail, shows the "ant's" body as a pair of fiery lobes protruding from a dying, Sun- like star. The Ant Nebula is located between 3,000 and 6,000 light years from Earth in the southern constellation Norma. The image challenges old ideas about what happens to dying stars. This observation, along with other pictures of various remnants of dying stars called planetary nebulae, shows that our Sun's fate will probably be much more interesting, complex and dramatic than astronomers previously believed. Although the ejection of gas from the dying star in the Ant Nebula is violent, it does not show the chaos one might expect from an ordinary explosion, but instead shows symmetrical patterns. One possibility is that the central star has a closely orbiting companion whose gravitational tidal forces shape the outflowing gas. A second possibility is that as the dying star spins, its strong magnetic fields are wound up into complex shapes like spaghetti in an eggbeater. Electrically charged winds, much like those in our Sun's solar wind but millions of times denser and moving at speeds up to 1,000 kilometers per second (more than 600 miles per second) from the star, follow the twisted field lines on their way out into space. The Space Telescope Science Institute, Baltimore, Md., manages space operations for the Hubble Space Telescope for NASA's Office of Space Science, Washington, D.C. The Institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA under contract with NASA's Goddard Space Flight Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. JPL is a division of the California Institute of Technology in Pasadena. Additional information about the Hubble Space Telescope is available at http://www.stsci.edu . More information about the Wide Field and Planetary Camera 2 is available at http://wfpc2.jpl.nasa.gov. |
| Date |
12.10.1999 |
|
N44C nebula
| Title |
N44C nebula |
| Description |
Resembling the hair in Botticelli's famous portrait of the birth of Venus, an image from NASA's Hubble Space Telescope has captured softly glowing filaments streaming from hot young stars in a nearby nebula. The image, presented by the Hubble Heritage Project, was taken in 1996 by Hubble's Wide Field and Planetary Camera 2, designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif. The image is available online at http://heritage.stsci.edu , http://oposite.stsci.edu/pubinfo/pr/2002/12 orhttp://www.jpl.nasa.gov/images/wfpc . On the top right of the image is a source of its artistic likeness, a network of nebulous filaments surrounding the Wolf-Rayet star. This type of rare star is characterized by an exceptionally vigorous "wind" of charged particles. The shock of the wind colliding with the surrounding gas causes the gas to glow. The Wolf-Rayet star is part of N44C, a nebula of glowing hydrogen gas surrounding young stars in the Large Magellanic Cloud. Visible from the Southern Hemisphere, the Large Magellanic Cloud is a small companion galaxy to the Milky Way. What makes N44C peculiar is the temperature of the star that illuminates it. The most massive stars -- those that are 10 to 50 times more massive than the Sun -- have maximum temperatures of 30,000 to 50,000 degrees Celsius (54,000 to 90,000 degrees Fahrenheit). The temperature of this star is about 75,000 degrees Celsius (135,000 degrees Fahrenheit). This unusually high temperature may be due to a neutron star or black hole that occasionally produces X-rays but is now inactive. N44C is part of a larger complex that includes young, hot, massive stars, nebulae, and a "superbubble" blown out by multiple supernova explosions. Part of the superbubble is seen in red at the very bottom left of the Hubble image. The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract with the Goddard Space Flight Center, Greenbelt, MD. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. |
| Date |
12.03.1999 |
|
Rotten Egg Nebula
| Title |
Rotten Egg Nebula |
| Description |
Violent gas collisions that produced supersonic shock fronts in a dying star are seen in a new, detailed image from NASA's Hubble Space Telescope. The picture, taken by Hubble's Wide Field and Planetary Camera 2, is online at http://www.jpl.nasa.gov/images/wfpc . The camera was designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Stars like our Sun will eventually die and expel most of their material outward into shells of gas and dust. These shells eventually form some of the most beautiful objects in the universe, called planetary nebulae."This new image gives us a rare view of the early death throes of stars like our Sun. For the first time, we can see phenomena leading to the formation of planetary nebulae. Until now, this had only been predicted by theory, but had never been seen directly," said Dr. Raghvendra Sahai, research scientist and member of the science team at JPL for the Wide Field and Planetary Camera 2. The object is sometimes called the Rotten Egg Nebula, because it contains a lot of sulphur, which would produce an awful odor if one could smell in space. The object is also known as the Calabash Nebula or by the technical name OH231.8+4.2. The densest parts of the nebula are composed of material ejected recently by the central star and accelerated in opposite directions. This material, shown as yellow in the image, is zooming away at speeds up to one and a half million kilometers per hour (one million miles per hour). Most of the star's original mass is now contained in these bipolar gas structures. A team of Spanish and American astronomers used NASA's Hubble Space Telescope to study how the gas stream rams into the surrounding material, shown in blue. They believe that such interactions dominate the formation process in planetary nebulae. Due to the high speed of the gas, shock-fronts are formed on impact and heat the surrounding gas. Although computer calculations have predicted the existence and structure of such shocks for some time, previous observations have not been able to prove the theory. This new Hubble image used filters that only let through light from ionized hydrogen and nitrogen atoms. Astronomers were able to distinguish the warmest parts of the gas heated by the violent shocks and found that they form a complex double-bubble shape. The bright yellow-orange colors in the picture show how dense, high-speed gas is flowing from the star, like supersonic speeding bullets ripping through a medium in opposite directions. The central star itself is hidden in the dusty band at the center. Much of the gas flow observed today seems to stem from a sudden acceleration that took place only about 800 years ago. The astronomers believe that 1,000 years from now, the Calabash Nebula will become a fully developed planetary nebula, like a butterfly emerging from its cocoon. The Calabash Nebula is 1.4 light years (more than 8 trillion miles) long and located some 5,000 light years (2,900 trillion, miles) from Earth in the constellation Puppis. The image was taken in December 2000 by the Wide Field and Planetary Camera 2. The image was originally released by the Hubble European Space Agency Information Centre, with a website at http://sci.esa.int/hubble. Additional information about the Hubble Space Telescope is online at http://www.stsci.edu . More information about the Wide Field and Planetary Camera 2 is at http://wfpc2.jpl.nasa.gov . Other scientists on the team include Valentin Bujarrabal and Javier Alcolea of Observatorio Astronomico Nacional, Spain, and Carmen Sanchez Contreras of JPL. The Space Telescope Science Institute, Baltimore, Md., manages space operations for Hubble for NASA's Office of Space Science, Washington, D.C. The institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract with the Goddard Space Flight Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. JPL is a division of the California Institute of Technology in Pasadena. |
| Date |
12.02.1999 |
|
Doradus Nebula
| Title |
Doradus Nebula |
| Description |
A panoramic view of a vast, sculpted area of gas and dust where thousands of stars are being born has been captured by NASA's Hubble Space Telescope. The image, taken by Hubble's Wide Field and Planetary Camera 2, is online at http://oposite.stsci.edu/pubinfo/pr/2001/21 and http://www.jpl.nasa.gov/images/wfpc . The camera was designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif. The photo offers an unprecedented, detailed view of the entire inner region of the fertile, star-forming 30 Doradus Nebula. The mosaic picture shows that ultraviolet radiation and high-speed material unleashed by the stars in the cluster, called R136 (the large blue blob left of center), are weaving a tapestry of creation and destruction, triggering the collapse of looming gas and dust clouds and forming pillar-like structures that incubate newborn stars. The 30 Doradus Nebula is in the Large Magellanic Cloud, a satellite galaxy of the Milky Way located 170,000 light-years from Earth. Nebulas like 30 Doradus are signposts of recent star birth. High-energy ultraviolet radiation from young, hot, massive stars in R136 causes surrounding gaseous material to glow. Previous Hubble telescope observations showed that R136 contains several dozen of the most massive stars known, each about 100 times the mass of the Sun and about 10 times as hot. These stellar behemoths formed about 2 million years ago. The stars in R136 produce intense "stellar winds," streams of material traveling at several million miles an hour. These winds push the gas away from the cluster and compress the inner regions of the surrounding gas and dust clouds (seen in the image as the pinkish material). The intense pressure triggers the collapse of parts of the clouds, producing a new star formation around the central cluster. Most stars in the nursery are not visible because they are still encased in cocoons of gas and dust. This mosaic image of 30 Doradus consists of five overlapping pictures taken between January 1994 and September 2000 by the Wide Field and Planetary Camera 2. Several color filters enhance important details in the stars and the nebula. Blue corresponds to the hot stars. The greenish color denotes hot gas energized by the central cluster of stars. Pink depicts the glowing edges of the gas and dust clouds facing the cluster, which are being bombarded by winds and radiation. Reddish-brown represents the cooler surfaces of the clouds, which are not receiving direct radiation from the central cluster. Additional information about the Hubble Space Telescope is at http://www.stsci.edu . More information about the Wide Field and Planetary Camera 2 is at http://wfpc2.jpl.nasa.gov . The Space Telescope Science Institute, Baltimore, Md., manages space operations for Hubble for NASA's Office of Space Science, Washington, D.C. The institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract with the Goddard Space Flight, Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. JPL is a division of the California Institute of Technology in Pasadena. |
| Date |
12.01.1999 |
|
Thackeray's Globules
| Title |
Thackeray's Globules |
| Description |
Inc., for NASA under contract with the Goddard Space Flight Center, Greenbelt, Md. The Hubble Space Telescope is a project of international cooperation between the European Space Agency and NASA. The California Institute of Technology in Pasadena manages JPL for NASA., Strangely glowing, floating dark clouds are silhouetted against nearby bright stars in a busy star-forming region viewed by NASA's Hubble Space Telescope. The image showing dense, opaque dust clouds - known as globules - in the star-forming region IC 2944 is available online at http://heritage.stsci.edu or http://oposite.stsci.edu/pubinfo/pr/2002/01 or http://www.jpl.nasa.gov/images/wfpc . It was taken by Hubble's Wide Field and Planetary Camera 2, designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Little is known about the origin and nature of these globules in IC 2944, which were first found by astronomer A.D. Thackeray in 1950. Globules are generally associated with large hydrogen-emitting star-formation regions, which give off the glowing light of hydrogen gas. The largest globule in this image consists of two separate clouds that gently overlap along our line of sight. Each cloud is nearly 1.4 light-years along its longest dimension. Collectively, they contain enough material to equal more than 15 times the mass of our Sun. The surrounding hydrogen-rich region, IC 2944, is filled with gas and dust illuminated and heated by a loose cluster of stars that are much hotter and more massive than our Sun. IC 2944 is relatively close by, only 5,900 light-years away in the constellation Centaurus. Using the remarkable resolution of Hubble, astronomers can for the first time study the intricate structure of these globules. They appear to be heavily fractured, as if major forces were tearing them apart. When radio astronomers observed the faint hiss of molecules within the globules, they realized that the globules are actually in constant, churning motion, moving supersonically among each other. This may be caused by powerful ultraviolet radiation from the luminous, massive stars, which heat up hydrogen gas in the region. The gas expands and streams against the globules, leading to their destruction. Despite their serene appearance, the globules may actually be likened to clumps of butter put into a red-hot pan. The globules are most likely dense clumps of gas and dust that existed before the hot, massive stars were born. But once the stars began to irradiate and destroy their surroundings, the clumps became visible when their less dense surroundings were eroded away. This exposed them to the full brunt of the ultraviolet radiation and the expanding hydrogen-rich region. The new images catch a glimpse of the process of destruction. The hydrogen-emission image that clearly shows the outline of the dark globules was taken with Hubble's camera in February 1999 by Bo Reipurth, University of Hawaii, Honolulu, and collaborators. Additional broadband images that helped to establish the true color of the stars in the field were taken by the Hubble Heritage Team in February 2001. The composite result is a four-color image. The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, |
| Date |
12.02.1999 |
|
ASTER Andes
PIA02654
Sol (our sun)
ASTER
| Title |
ASTER Andes |
| Original Caption Released with Image |
In this image of the Andes along the Chile-Bolivia border, the visible and infrared data have been computer enhanced to exaggerate the color differences of the different materials. The scene is dominated by the Pampa Luxsar lava complex, occupying the upper right two-thirds of the scene. Lava flows are distributed around remnants of large dissected cones, the largest of which is Cerro Luxsar. On the middle left edge of the image are the Olca and Parumastrato volcanoes, which appear in blue due to a lack of vegetation (colored red in this composite). This image covers an area 60 kilometers (37 miles) wide and 60 kilometers (37 miles) long in three bands of the reflected visible and infrared wavelength region. It was acquired on April 7, 2000. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
|
ASTER Images San Francisco B
…
PIA02606
Sol (our sun)
ASTER
| Title |
ASTER Images San Francisco Bay Area |
| Original Caption Released with Image |
This image of the San Francisco Bay region was acquired on March 3, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters about 50 to 300 feet ), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet. Image: This image covers an area 60 kilometers (37 miles) wide and 75 kilometers (47 miles) long in three bands of the reflected visible and infrared wavelength region. The combination of bands portrays vegetation in red, and urban areas in gray. Sediment in the Suisun Bay, San Pablo Bay, San Francisco Bay, and the Pacific Ocean shows up as lighter shades of blue. Along the west coast of the San Francisco Peninsula, strong surf can be seen as a white fringe along the shoreline. A powerful rip tide is visible extending westward from Daly City into the Pacific Ocean. In the lower right corner, the wetlands of the South San Francisco Bay National Wildlife Refuge appear as large dark blue and brown polygons. The high spatial resolution of ASTER allows fine detail to be observed in the scene. The main bridges of the area (San Mateo, San Francisco-Oakland Bay, Golden Gate, Richmond-San Rafael, Benicia-Martinez, and Carquinez) are easily picked out, connecting the different communities in the Bay area. Shadows of the towers along the Bay Bridge can be seen over the adjacent bay water. With enlargement the entire road network can be easily mapped, individual buildings are visible, including the shadows of the high-rises in downtown San Francisco. Inset: This enlargement of the San Francisco Airport highlights the high spatial resolution of ASTER. With further enlargement and careful examination, airplanes can be seen at the terminals. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example, applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
|
ASTER Images Tokyo
PIA02607
Sol (our sun)
ASTER
| Title |
ASTER Images Tokyo |
| Original Caption Released with Image |
This image of the city of Tokyo was acquired on March 22, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image the Earth for the next 6 years to map and monitor the changing surface of our planet. This false color infrared image covers an area 60 km wide and 75 km long in three bands of the short wavelength infrared region, with a spatial resolution of 15 m. It shows part of the Tokyo metropolitan area extending south to Yokohama, included are the Ginza District, Haneda airport and the Imperial Palace. To the west, Tokyo is hemmed in by mountains, covered with forests (displayed in red), on the southeast, Tokyo Bay is one of the world's great harbors. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
|
ASTER Images San Francisco B
…
PIA02605
Sol (our sun)
ASTER
| Title |
ASTER Images San Francisco Bay Area |
| Original Caption Released with Image |
These images of the San Francisco Bay region were acquired on March 3, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. Each covers an area 60 kilometers (37 miles) wide and 75 kilometers (47 miles) long. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image the Earth for the next 6 years to map and monitor the changing surface of our planet. Upper Left: The color infrared composite uses bands in the visible and reflected infrared. Vegetation is red, urban areas are gray, sediment in the bays shows up as lighter shades of blue. Thanks to the 15 meter (50-foot) spatial resolution, shadows of the towers along the Bay Bridge can be seen. Upper right: A composite of bands in the short wave infrared displays differences in soils and rocks in the mountainous areas. Even though these regions appear entirely vegetated in the visible, enough surface shows through openings in the vegetation to allow the ground to be imaged. Lower left: This composite of multispectral thermal bands shows differences in urban materials in varying colors. Separation of materials is due to differences in thermal emission properties, analogous to colors in the visible. Lower right: This is a color coded temperature image of water temperature, derived from the thermal bands. Warm waters are in white and yellow, colder waters are blue. Suisun Bay in the upper right is fed directly from the cold Sacramento River. As the water flows through San Pablo and San Francisco Bays on the way to the Pacific, the waters warm up. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands, evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
|
Typhoon Nanmadol
PIA07100
Sol (our sun)
SeaWinds Scatterometer
| Title |
Typhoon Nanmadol |
| Original Caption Released with Image |
1 Dec. 2004 This image, produced from data collected by the SeaWinds scatterometer instrument onboard NASA's QuikScat mission reveals the details of the surface winds and rain in Typhoon Nanmadol as it moves westward. The data was collected on 1 Dec. 2004 at approximately 8 in the morning. SeaWinds uses radar to peer through clouds and darkness to measure the near-surface wind speed over the ocean on a daily global basis. In this image of Typhoon Nanmadol, ocean wind speed is shown in color with wind barbs showing the wind direction. The Typhoon eye is visible as a brown patch within the purple area of most intense wind speeds (50+ knots) and rain. The red area of high winds (30+ knots) extends over 800 km around the eye. The grey area in the center left is the Island of Yap. The typhoon is moving about 28 mph to the west-northwest and is gathering strength before it hits the Phillipines a few days later, leading to 1000 casulties according to Reuters. In recent years, the ability to detect and track severe storms has been dramatically enhanced by the advent of weather satellites. Data from the SeaWinds scatterometer is augmenting traditional satellite images of clouds by providing direct measurements of surface winds to compare with the observed cloud patterns in an effort to better determine a hurricane's location, direction, structure, and strength. Specifically, these wind data are helping meteorologists to more accurately identify the extent of gale-force winds associated with a storm, while supplying inputs to numerical models that provide advanced warning of high waves and flooding. "QuikScat Background" NASA's Quick Scatterometer (QuikScat) spacecraft was launched from Vandenberg Air Force Base, California on June 19, 1999. QuikScat carries the SeaWinds scatterometer, a specialized microwave radar that measures near-surface wind speed and direction under all weather and cloud conditions over the Earth's oceans. More information about the QuikScat mission and observations is available at http://winds.jpl.nasa.gov [ http://photojournal.jpl.nasa.gov/catalog/PIA07100 http://winds.jpl.nasa.gov ]. QuikScat is managed for NASA's Science Mission Directorate, Washington, DC, by NASA's Jet Propulsion Laboratory, Pasadena, CA. JPL also built the SeaWinds radar instrument and is providing ground science processing systems. NASA's Goddard Space Flight Center, Greenbelt, MD, managed development of the satellite, designed and built by Ball Aerospace & Technologies Corp., Boulder, CO. The National Oceanic and Atmospheric Administration has contributed support to ground systems processing and related activities. |
|
ASTER Suez Canal
PIA02661
Sol (our sun)
ASTER
| Title |
ASTER Suez Canal |
| Original Caption Released with Image |
One of the most important waterways in the world, the Suez Canal runs north to south across the Isthmus of Suez in northeastern Egypt. This image of the canal covers an area 36 kilometers (22 miles) wide and 60 kilometers (47 miles) long in three bands of the reflected visible and infrared wavelength region. It shows the northern part of the canal, with the Mediterranean Sea just visible in the upper right corner. The Suez Canal connects the Mediterranean Sea with the Gulf of Suez, an arm of the Red Sea. The artificial canal provides an important shortcut for ships operating between both European and American ports and ports located in southern Asia, eastern Africa, and Oceania. With a length of about 195 kilometers (121 miles) and a minimum channel width of 60 meters (197 feet), the Suez Canal is able to accommodate ships as large as 150,000 tons fully loaded. Because no locks interrupt traffic on this sea level waterway, the transit time only averages about 15 hours. ASTER acquired this scene on May 19, 2000. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal, change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
|
ASTER Washington, D.C.
PIA02655
Sol (our sun)
ASTER
| Title |
ASTER Washington, D.C. |
| Original Caption Released with Image |
The White House, the Jefferson Memorial, and the Washington Monument with its shadow are all visible in this image of Washington, D.C. With its 15-meter spatial resolution, ASTER can see individual buildings. Taken on June 1, 2000, this image covers an area 14 kilometers (8.5 miles) wide and 13.7 kilometers (8.2 miles) long in three bands of the reflected visible and infrared wavelength region. The combination of visible and near infrared bands displays vegetation in red and water in dark grays. The Potomac River flows from the middle left to the bottom center. The large red area west of the river is Arlington National Cemetery. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
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ASTER Waves
PIA02662
Sol (our sun)
ASTER
| Title |
ASTER Waves |
| Original Caption Released with Image |
The pattern on the right half of this image of the Bay of Bengal is the result of two opposing wave trains colliding. This ASTER sub-scene, acquired on March 29, 2000, covers an area 18 kilometers (13 miles) wide and 15 kilometers (9 miles) long in three bands of the reflected visible and infrared wavelength region. The visible and near-infrared bands highlight surface waves due to specular reflection of sunlight off of the wave faces. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
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ASTER Images Mt. Usu Volcano
PIA02608
Sol (our sun)
ASTER
| Title |
ASTER Images Mt. Usu Volcano |
| Original Caption Released with Image |
On April 3, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra Satellite captured this image of the erupting Mt. Usu volcano in Hokkaido, Japan. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image the Earth for the next 6 years to map and monitor the changing surface of our planet. This false color infrared image of Mt Usu volcano is dominated by Lake Toya, an ancient volcanic caldera. On the south shore is the active Usu volcano. On Friday, March 31, more than 11,000 people were evacuated by helicopter, truck and boat from the foot of Usu, that began erupting from the northwest flank, shooting debris and plumes of smoke streaked with blue lightning thousands of feet in the air. Although no lava gushed from the mountain, rocks and ash continued to fall after the eruption. The region was shaken by thousands of tremors before the eruption. People said they could taste grit from the ash that was spewed as high as 2,700 meters (8,850 ft) into the sky and fell to coat surrounding towns with ash. "Mount Usu has had seven significant eruptions that we know of, and at no time has it ended quickly with only a small scale eruption," said Yoshio Katsui, a professor at Hokkaido University. This was the seventh major eruption of Mount Usu in the past 300 years. Fifty people died when the volcano erupted in 1822, its worst known eruption. In the image, most of the land is covered by snow. Vegetation, appearing red in the false color composite, can be seen in the agricultural fields, and forests in the mountains. Mt. Usu is crossed by three dark streaks. These are the paths of ash deposits that rained out from eruption plumes two days earlier. The prevailing wind was from the northwest, carrying the ash away from the main city of Date. Ash deposited can be traced on the image as far away as 10 kilometers (16 miles) from the volcano. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in, numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
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ASTER Paris
PIA02660
Sol (our sun)
ASTER
| Title |
ASTER Paris |
| Original Caption Released with Image |
The Eiffel Tower and its shadow can be seen next to the Seine in the left middle of this ASTER image of Paris. Based on the length of the shadow and the solar elevation angle of 59 degrees, we can calculate its height as 324 meters (1,054 feet), compared to its actual height of 303 meters (985 feet). Acquired on July 23, 2000, this image covers an area 23 kilometers (15 miles) wide and 20 kilometers (13 miles) long in three bands of the reflected visible and infrared wavelength region. Known as the City of Light, Paris has been extolled for centuries as one of the great cities of the world. Its location on the Seine River, at a strategic crossroads of land and river routes, has been the key to its expansion since the Parisii tribe first settled here in the 3rd century B.C. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties;, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
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ASTER Gibraltar
PIA02657
Sol (our sun)
ASTER
| Title |
ASTER Gibraltar |
| Original Caption Released with Image |
The Strait of Gibraltar separates Spain from Morocco. This image, acquired on July 5, 2000, covers an area 34 kilometers (21 miles) wide and 59 kilometers (37 miles) long in three bands of the reflected visible and infrared wavelength region. The promontory on the eastern side of the conspicuous Spanish port is the Rock of Gibraltar. Once one of the two classical Pillars of Hercules, the Rock was crowned with silver columns by Phoenician mariners to mark the limits of safe navigation for the ancient Mediterranean peoples. The rocky promontory still commands the western entrance to the Mediterranean Sea. The rocky limestone and shale ridge rises abruptly from the sea, to a maximum elevation of 426 meters (1,398 feet). A British colony, Gibraltar occupies a narrow strip of land at the southernmost tip of the Iberian Peninsula. It is separated from the Spanish mainland by a neutral zone contained on a narrow, sandy isthmus. Because of its strategic location and formidable topography, Gibraltar serves mainly as a British fortress. Most of its sparse land is taken up by air and naval installations, and the civilian population is small. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists, in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
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ASTER Mexicali
PIA02659
Sol (our sun)
ASTER
| Title |
ASTER Mexicali |
| Original Caption Released with Image |
Dramatic differences in land use patterns are highlighted in this image of the U.S.-Mexico border. Lush, regularly gridded agricultural fields on the U.S. side contrast with the more barren fields of Mexico This June 12, 2000, sub-scene combines visible and near infrared bands, displaying vegetation in red. The town of Mexicali-Calexico spans the border in the middle of the image, El Centro, California, is in the upper left. Watered by canals fed from the Colorado River, California's Imperial Valley is one of the country's major fruit and vegetable producers. This image covers an area 24 kilometers (15 miles) wide and 30 kilometers (19 miles) long in three bands of the reflected visible and infrared wavelength region. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and, geology, and measuring surface heat balance. |
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ASTER Images the Island of H
…
PIA02604
Sol (our sun)
ASTER
| Title |
ASTER Images the Island of Hawaii |
| Original Caption Released with Image |
These images of the Island of Hawaii were acquired on March 19, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet. Data are shown from the short wavelength and thermal infrared spectral regions, illustrating how different and complementary information is contained in different parts of the spectrum. Left image: This false-color image covers an area 60 kilometers (37 miles) wide and 120 kilometers (75 miles) long in three bands of the short wavelength infrared region. While, much of the island was covered in clouds, the dominant central Mauna Loa volcano, rising to an altitude of 4115 meters (13,500 feet), is cloud-free. Lava flows can be seen radiating from the central crater in green and black tones. As they reach lower elevations, the flows become covered with vegetation, and their image color changes to yellow and orange. Mauna Kea volcano to the north of Mauna Loa has a thin cloud-cover, producing a bluish tone on the image. The ocean in the lower right appears brown due to the color processing. Right image: This image is a false-color composite of three thermal infrared bands. The brightness of the colors is proportional to the temperature, and the hues display differences in rock composition. Clouds are black, because they are the coldest objects in the scene. The ocean and thick vegetation appear dark green because they are colder than bare rock surfaces, and have no thermal spectral features. Lava flows are shades of magenta, green, pink and yellow, reflecting chemical changes due to weathering and relative age differences. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications, are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
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ASTER Dunes
PIA02656
Sol (our sun)
ASTER
| Title |
ASTER Dunes |
| Original Caption Released with Image |
This image of Saudi Arabia shows a great sea of linear dunes in part of the Rub' al Khali, or the Empty Quarter. Acquired on June 25, 2000, the image covers an area 37 kilometers (23 miles) wide and 28 kilometers (17 miles) long in three bands of the reflected visible and infrared wavelength region. The dunes are yellow due to the presence of iron oxide minerals. The inter-dune area is made up of clays and silt and appears blue due to its high reflectance in band 1. The Rub' al Khali is the world's largest continuous sand desert. It covers about 650,000 square kilometers (250,966 square miles) and lies mainly in southern Saudi Arabia, though it does extend into the United Arab Emirates, Oman, and Yemen. One of the world's driest areas, it is uninhabited except for the Bedouin nomads who cross it. The first European to travel through the desert was Bertram Thomas in 1930. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
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ASTER View of Sharm El Sheik
…
PIA02667
Sol (our sun)
ASTER
| Title |
ASTER View of Sharm El Sheik, Egypt |
| Original Caption Released with Image |
The Red Sea golf resort in Sharm El Sheik, Egypt, where President Clinton met with Israeli Prime Minister Ehud Barak and Palestinian Authority President Yasser Arafat, stands out against the desert landscape in this image acquired on August 25, 2000. This image of the southern tip of the Sinai Peninsula shows an area about 30 by 40 kilometers (19 by 25 miles) in the visible and near infrared wavelength region. Vegetation appears in red. The blue areas in the water at the top and bottom of the image are coral reefs. The airport is visible just to the north of the golf resort. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands Evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. |
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ASTER Tibet
PIA02658
Sol (our sun)
ASTER
| Title |
ASTER Tibet |
| Original Caption Released with Image |
The Kunlun fault is one of the gigantic strike-slip faults that bound the north side of Tibet. Left-lateral motion along the 1,500-kilometer (932-mile) length of the Kunlun has occurred uniformly for the last 40,000 years at a rate of 1.1 centimeter per year, creating a cumulative offset of more than 400 meters (1300 feet). In this image, two splays of the fault are clearly seen crossing from east to west. The northern fault juxtaposes sedimentary rocks of the mountains against alluvial fans. Its trace is also marked by lines of vegetation, which appear red in the image. The southern, younger fault cuts through the alluvium. A dark linear area in the center of the image is wet ground where groundwater has pounded against the fault. Measurements from the image of displacements of young streams that cross the fault show 15 to 75 meters (16 to 82 yards) of left-lateral offset. This image of Tibet covers an area 40 kilometers (25 miles) wide and 15 kilometers (10 miles) long in three bands of the reflected visible and infrared wavelength region. ASTER acquired the scene on July 20, 2000. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader, Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical, information for surface mapping and monitoring dynamic conditions and temporal change. Examples of applications include monitoring glacial advances and retreats, potentially active volcanoes, thermal pollution, and coral reef degradation, identifying crop stress, determining cloud morphology and physical properties, evaluating wetlands, mapping surface temperature of soils and geology, and measuring surface heat balance. |
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Tsunami Inundation, North of
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PIA06671
Sol (our sun)
ASTER, SIR-C/X-SAR
| Title |
Tsunami Inundation, North of Phuket, Thailand ASTER Images and SRTM Elevation Model |
| Original Caption Released with Image |
Figure 1 The Indian Ocean coastline north of Phuket, Thailand is a major tourist destination that was in the path of the tsunami produced by a giant offshore earthquake on December 26, 2004. This disaster resulted in a heavy loss of life. These simulated natural color ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) images show a 27 kilometer (17-mile) long stretch of coast 80 kilometers (50 miles) north of the Phuket airport in the Khao Lak area on December 31 (middle) and also two years earlier (left). The changes along the coast are obvious (changing from green to grey) where the vegetation was stripped away by the tsunami. The image on the right is a copy of the later ASTER scene but it includes highlighting in red for areas that have elevations within 10 meters (33 feet) of sea level. This elevation information was supplied by the Shuttle Radar Topography Mission (SRTM). The red areas appear to include most of the tsunami inundated areas. The geographic correspondence of the imaged damage and the highlighted elevation range is quite good in the middle and upper parts of the scene and is consistent with an early field report of about 10 meters of inundation. In the south, the elevation range corresponds to a much wider area than the actual damage, but this is to be expected for areas increasingly far from the coast. Offshore bathymetry (depth variations), coastal landforms, distance from the coast, and additional factors other than elevation range control the damage extent. But elevation measurements along the coast, as provided by SRTM, give a general indication of areas at risk, as now confirmed by ASTER. ASTER images Earth to map and monitor the changing surface of our planet with its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet). These data provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour,, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. Size: 9.75 x 27.6 kilometers (6.0 x 17.1 miles), Location: 8.6 degrees North latitude, 98.3 degrees East longitude Orientation: Top is 8.25 degrees east of North Image Data: ASTER Bands 1, 2, 3 mixed for simulated true color. Date Acquired: November 15, 2002 and December 31, 2004 (ASTER), February 2000 (SRTM) |
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Tsunami Inundation, North of
…
PIA06671
Sol (our sun)
ASTER, SIR-C/X-SAR
| Title |
Tsunami Inundation, North of Phuket, Thailand ASTER Images and SRTM Elevation Model |
| Original Caption Released with Image |
Figure 1 The Indian Ocean coastline north of Phuket, Thailand is a major tourist destination that was in the path of the tsunami produced by a giant offshore earthquake on December 26, 2004. This disaster resulted in a heavy loss of life. These simulated natural color ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) images show a 27 kilometer (17-mile) long stretch of coast 80 kilometers (50 miles) north of the Phuket airport in the Khao Lak area on December 31 (middle) and also two years earlier (left). The changes along the coast are obvious (changing from green to grey) where the vegetation was stripped away by the tsunami. The image on the right is a copy of the later ASTER scene but it includes highlighting in red for areas that have elevations within 10 meters (33 feet) of sea level. This elevation information was supplied by the Shuttle Radar Topography Mission (SRTM). The red areas appear to include most of the tsunami inundated areas. The geographic correspondence of the imaged damage and the highlighted elevation range is quite good in the middle and upper parts of the scene and is consistent with an early field report of about 10 meters of inundation. In the south, the elevation range corresponds to a much wider area than the actual damage, but this is to be expected for areas increasingly far from the coast. Offshore bathymetry (depth variations), coastal landforms, distance from the coast, and additional factors other than elevation range control the damage extent. But elevation measurements along the coast, as provided by SRTM, give a general indication of areas at risk, as now confirmed by ASTER. ASTER images Earth to map and monitor the changing surface of our planet with its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet). These data provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance. ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour,, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. Size: 9.75 x 27.6 kilometers (6.0 x 17.1 miles), Location: 8.6 degrees North latitude, 98.3 degrees East longitude Orientation: Top is 8.25 degrees east of North Image Data: ASTER Bands 1, 2, 3 mixed for simulated true color. Date Acquired: November 15, 2002 and December 31, 2004 (ASTER), February 2000 (SRTM) |
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