|
|
Spitzer and Hubble Capture E
…
| Title |
Spitzer and Hubble Capture Evolving Planetary Systems |
|
Aura/OMI Ozone Hole from Sep
…
| Title |
Aura/OMI Ozone Hole from September 12, 2004 to November 15, 2004 with Polar Vortex Demarced |
| Abstract |
Data from NASA satellites establishes a 40-year record of stratospheric ozone measurements. The stratospheric ozone layer shields life on Earth from harmful solar ultraviolet (UV) radiation. Research shows that excess exposure to UV radiation causes skin cancer and eye problems and impacts plant growth. Global stratospheric ozone has decreased by 3 percent globally between 1980 and 2000 and has thinned by 50 percent over Antarctica in winter and spring. Depletion of the ozone layer allows more UV radiation to reach the Earth's surface. This animation shows the ozone layer blocking harmful UV radiation from the Earth's surface. The hole in the ozone is seen in purple. The location, size, and shape of the polar vortex is derived from potential vorticity data, PV. The PV, shown in white at 550 degrees Kelvin, is an atmospheric regional event that isolates polar air from the air at lower latitudes, producing conditions favorable for wintertime polar ozone depletion. The animation shows that most of the low-temperature and chemically-perturbed region is confined within the polar vortex during the Antarctic winter. |
| Completed |
2004-11-30 |
|
Aura/OMI Ozone Hole from Sep
…
| Title |
Aura/OMI Ozone Hole from September 12, 2004 to November 15, 2004 with Polar Vortex Demarced |
| Abstract |
Data from NASA satellites establishes a 40-year record of stratospheric ozone measurements. The stratospheric ozone layer shields life on Earth from harmful solar ultraviolet (UV) radiation. Research shows that excess exposure to UV radiation causes skin cancer and eye problems and impacts plant growth. Global stratospheric ozone has decreased by 3 percent globally between 1980 and 2000 and has thinned by 50 percent over Antarctica in winter and spring. Depletion of the ozone layer allows more UV radiation to reach the Earth's surface. This animation shows the ozone layer blocking harmful UV radiation from the Earth's surface. The hole in the ozone is seen in purple. The location, size, and shape of the polar vortex is derived from potential vorticity data, PV. The PV, shown in white at 550 degrees Kelvin, is an atmospheric regional event that isolates polar air from the air at lower latitudes, producing conditions favorable for wintertime polar ozone depletion. The animation shows that most of the low-temperature and chemically-perturbed region is confined within the polar vortex during the Antarctic winter. |
| Completed |
2004-11-30 |
|
Aura/OMI Ozone Hole from Sep
…
| Title |
Aura/OMI Ozone Hole from September 12, 2004 to November 15, 2004 with Polar Vortex Demarced |
| Abstract |
Data from NASA satellites establishes a 40-year record of stratospheric ozone measurements. The stratospheric ozone layer shields life on Earth from harmful solar ultraviolet (UV) radiation. Research shows that excess exposure to UV radiation causes skin cancer and eye problems and impacts plant growth. Global stratospheric ozone has decreased by 3 percent globally between 1980 and 2000 and has thinned by 50 percent over Antarctica in winter and spring. Depletion of the ozone layer allows more UV radiation to reach the Earth's surface. This animation shows the ozone layer blocking harmful UV radiation from the Earth's surface. The hole in the ozone is seen in purple. The location, size, and shape of the polar vortex is derived from potential vorticity data, PV. The PV, shown in white at 550 degrees Kelvin, is an atmospheric regional event that isolates polar air from the air at lower latitudes, producing conditions favorable for wintertime polar ozone depletion. The animation shows that most of the low-temperature and chemically-perturbed region is confined within the polar vortex during the Antarctic winter. |
| Completed |
2004-11-30 |
|
Aura/OMI Ozone Hole from Sep
…
| Title |
Aura/OMI Ozone Hole from September 12, 2004 to November 15,2004 |
| Abstract |
Data from NASA satellites establishes a 40 year record of stratospheric ozone measurements. The stratospheric ozone layer shields life on Earth from harmful solar ultraviolet (UV) radiation. Research shows that excess exposure to UV radiation causes skin cancer and eye problems and impacts plant growth. Global stratospheric ozone has decreased by 3 percent globally between 1980 and 2000 and has thinned by 50 percent over Antarctica in winter and spring. Depletion of the ozone layer allows more UV radiation to reach the Earth's surface. This animation shows the ozone layer blocking harmful UV radiation from the Earth's surface. The hole in the ozone is seen in purple. |
| Completed |
2004-11-30 |
|
Aura/OMI Ozone Hole from Sep
…
| Title |
Aura/OMI Ozone Hole from September 12, 2004 to November 15,2004 |
| Abstract |
Data from NASA satellites establishes a 40 year record of stratospheric ozone measurements. The stratospheric ozone layer shields life on Earth from harmful solar ultraviolet (UV) radiation. Research shows that excess exposure to UV radiation causes skin cancer and eye problems and impacts plant growth. Global stratospheric ozone has decreased by 3 percent globally between 1980 and 2000 and has thinned by 50 percent over Antarctica in winter and spring. Depletion of the ozone layer allows more UV radiation to reach the Earth's surface. This animation shows the ozone layer blocking harmful UV radiation from the Earth's surface. The hole in the ozone is seen in purple. |
| Completed |
2004-11-30 |
|
Global Ozone from 2000 throu
…
| Title |
Global Ozone from 2000 through 2003 (WMS) |
| Abstract |
This visualization shows the total ozone concentrations for the Earth from January 1, 2000 through December 31, 2003. Low ozone (less than 200 Dobson units) is depicted as regions of dark blue, with high ozone (greater than 330 Dobson units) depicted as yellow and red. The most visible and dynamic feature of the ozone distribution is the ozone hole that forms over Antartica during September of each year. The amount of ozone in the stratosphere over Antarctica is reduced during this period due to unique atmospheric conditions which chemically reduce the amount of ozone in the region and prevent that ozone from mixing with the higher ozone concentrations just outside the hole. Ozone blocks harmful ultraviolet 'B' rays, and loss of statospheric ozone has been linked to skin cancer in humans and other adverse biological effects in plants and animals. The 2000 Antarctic ozone hole reached 11.5 million square miles on September 10, 2000, the largest hole ever recorded, slightly larger than the North American continent. The 2002 ozone hole was much smaller than normal, dividing into two parts on September 24 before dissipating completely, while the 2003 hole was the second largest observed, reaching 10.9 million square miles on September 11. This data was measured by the TOMS instrument on the Earth Probe satellite. TOMS experienced some days during this period for which data was not measured due to instrument problems. |
| Completed |
2004-07-12 |
|
Global Ozone from 2000 throu
…
| Title |
Global Ozone from 2000 through 2003 (WMS) |
| Abstract |
This visualization shows the total ozone concentrations for the Earth from January 1, 2000 through December 31, 2003. Low ozone (less than 200 Dobson units) is depicted as regions of dark blue, with high ozone (greater than 330 Dobson units) depicted as yellow and red. The most visible and dynamic feature of the ozone distribution is the ozone hole that forms over Antartica during September of each year. The amount of ozone in the stratosphere over Antarctica is reduced during this period due to unique atmospheric conditions which chemically reduce the amount of ozone in the region and prevent that ozone from mixing with the higher ozone concentrations just outside the hole. Ozone blocks harmful ultraviolet 'B' rays, and loss of statospheric ozone has been linked to skin cancer in humans and other adverse biological effects in plants and animals. The 2000 Antarctic ozone hole reached 11.5 million square miles on September 10, 2000, the largest hole ever recorded, slightly larger than the North American continent. The 2002 ozone hole was much smaller than normal, dividing into two parts on September 24 before dissipating completely, while the 2003 hole was the second largest observed, reaching 10.9 million square miles on September 11. This data was measured by the TOMS instrument on the Earth Probe satellite. TOMS experienced some days during this period for which data was not measured due to instrument problems. |
| Completed |
2004-07-12 |
|
Antarctic Ozone from TOMS: A
…
| Title |
Antarctic Ozone from TOMS: August 1, 2003 to September 23, 2003 |
| Abstract |
The 2003 Antarctic ozone hole was the second largest ever observed, according to scientists from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Naval Research Laboratory (NRL). The Antarctic ozone 'hole' is defined as thinning of the ozone layer over the continent to levels significantly below pre-1979 levels. Ozone blocks harmful ultraviolet 'B' rays. Loss of stratospheric ozone has been linked to skin cancer in humans and other adverse biological effects on plants and animals. The size of the 2003 Antarctic ozone hole reached 10.9 million square miles on September 11, 2003, slightly larger than the North American continent, but smaller than the largest ever recorded, on September 10, 2000, when it covered 11.5 million square miles. |
| Completed |
2003-09-23 |
|
Antarctic Ozone from TOMS: A
…
| Title |
Antarctic Ozone from TOMS: August 1, 2003 to September 23, 2003 |
| Abstract |
The 2003 Antarctic ozone hole was the second largest ever observed, according to scientists from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Naval Research Laboratory (NRL). The Antarctic ozone 'hole' is defined as thinning of the ozone layer over the continent to levels significantly below pre-1979 levels. Ozone blocks harmful ultraviolet 'B' rays. Loss of stratospheric ozone has been linked to skin cancer in humans and other adverse biological effects on plants and animals. The size of the 2003 Antarctic ozone hole reached 10.9 million square miles on September 11, 2003, slightly larger than the North American continent, but smaller than the largest ever recorded, on September 10, 2000, when it covered 11.5 million square miles. |
| Completed |
2003-09-23 |
|
Antarctic Ozone from TOMS: A
…
| Title |
Antarctic Ozone from TOMS: August 1, 2003 to September 23, 2003 |
| Abstract |
The 2003 Antarctic ozone hole was the second largest ever observed, according to scientists from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Naval Research Laboratory (NRL). The Antarctic ozone 'hole' is defined as thinning of the ozone layer over the continent to levels significantly below pre-1979 levels. Ozone blocks harmful ultraviolet 'B' rays. Loss of stratospheric ozone has been linked to skin cancer in humans and other adverse biological effects on plants and animals. The size of the 2003 Antarctic ozone hole reached 10.9 million square miles on September 11, 2003, slightly larger than the North American continent, but smaller than the largest ever recorded, on September 10, 2000, when it covered 11.5 million square miles. |
| Completed |
2003-09-23 |
|
Antarctic Ozone from TOMS: A
…
| Title |
Antarctic Ozone from TOMS: August 1, 2003 to September 23, 2003 |
| Abstract |
The 2003 Antarctic ozone hole was the second largest ever observed, according to scientists from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Naval Research Laboratory (NRL). The Antarctic ozone 'hole' is defined as thinning of the ozone layer over the continent to levels significantly below pre-1979 levels. Ozone blocks harmful ultraviolet 'B' rays. Loss of stratospheric ozone has been linked to skin cancer in humans and other adverse biological effects on plants and animals. The size of the 2003 Antarctic ozone hole reached 10.9 million square miles on September 11, 2003, slightly larger than the North American continent, but smaller than the largest ever recorded, on September 10, 2000, when it covered 11.5 million square miles. |
| Completed |
2003-09-23 |
|
Ozone Measurements from 2000
…
| Title |
Ozone Measurements from 2000 through 2003 (WMS) |
| Abstract |
This visualization shows the total ozone concentrations for the Earth from January 1, 2000 through December 31, 2003, as measured by theTOMS instrument on the Earth Probe satellite. Low ozone (less than 200 Dobson units) is depicted as regions of dark blue, with high ozone (greater that 330 Dobson units) depicted as yellow and red. The most visible and dynamic feature of the ozone distribution is the ozone hole that forms over Antartica during September of each year. The amount of ozone in the stratosphere over Antarctica is reduced during this period due to unique atmospheric conditions which chemically reduce the amount of ozone in the region and prevent that ozone from mixing with the higher ozone concentrations just outside the hole. Ozone blocks harmful ultraviolet 'B' rays, and loss of statospheric ozone has been linked to skin cancer in humans and other adverse biological effects in plants and animals. This visualization explicitly shows the TOM ozone data coverage and does not interpolate data into regions of the Earth that the instrument did not observe. Since TOMS measures ozone by observing the characteristics of sunlight reflected from the Earth's surface, no measurements are available for the poles during the polar winter, i.e., around January for the North Pole and July for the South Pole. Also, there is an unobserved region between successive satellite orbits around the equator. Finally, the instrument has periods where technical issues make measurement impossible for a matter of hours or days. This visualization shows that the dynamics of the ozone layer remain visible despite these measurement issues. |
| Completed |
2004-02-12 |
|
Ozone Measurements from 2000
…
| Title |
Ozone Measurements from 2000 through 2003 (WMS) |
| Abstract |
This visualization shows the total ozone concentrations for the Earth from January 1, 2000 through December 31, 2003, as measured by theTOMS instrument on the Earth Probe satellite. Low ozone (less than 200 Dobson units) is depicted as regions of dark blue, with high ozone (greater that 330 Dobson units) depicted as yellow and red. The most visible and dynamic feature of the ozone distribution is the ozone hole that forms over Antartica during September of each year. The amount of ozone in the stratosphere over Antarctica is reduced during this period due to unique atmospheric conditions which chemically reduce the amount of ozone in the region and prevent that ozone from mixing with the higher ozone concentrations just outside the hole. Ozone blocks harmful ultraviolet 'B' rays, and loss of statospheric ozone has been linked to skin cancer in humans and other adverse biological effects in plants and animals. This visualization explicitly shows the TOM ozone data coverage and does not interpolate data into regions of the Earth that the instrument did not observe. Since TOMS measures ozone by observing the characteristics of sunlight reflected from the Earth's surface, no measurements are available for the poles during the polar winter, i.e., around January for the North Pole and July for the South Pole. Also, there is an unobserved region between successive satellite orbits around the equator. Finally, the instrument has periods where technical issues make measurement impossible for a matter of hours or days. This visualization shows that the dynamics of the ozone layer remain visible despite these measurement issues. |
| Completed |
2004-02-12 |
|
Haze over Eastern China
| Title |
Haze over Eastern China |
| Description |
A nearly opaque plume of haze snaked through eastern China on October 20, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite took this picture the same day. This image shows thick haze hugging the slopes of the Taihang Shan Mountains as it pushes north toward Beijing. Just south of the city, however, the haze veers off to the east, blowing over Bo Hai. The haze likely results from industrial and vehicular emissions as China struggles to balance economic growth with a healthy environment. According to news reports, lung cancer rates in China rose 26.9 percent in males and 38.4 percent in females between 2000 and 2005, and air quality was expected to pose the greatest challenge to athletes in the 2008 Olympics. NASA image courtesy the MODIS Rapid Response Team [ http://rapidfire.sci.gsfc.nasa.gov ] at NASA GSFC. The Rapid Response Team provides daily images [ http://rapidfire.sci.gsfc.nasa.gov/subsets/?FAS_China4 ] of this region. |
|
Three Years of Saturn
| Title |
Three Years of Saturn |
| Explanation |
Using an image recorded just last month as a base, this composite illustration tracks the motion of bright Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap070406.html ] as it wanders through planet Earth's night sky [ http://soc.jpl.nasa.gov/viewing.cfm ]. Starting at the upper right, Saturn's position is shown about every two weeks beginning in August 2005 and projected through September 2008. Over the three year period, Saturn actually appears to reverse its general eastward (leftward) drift, tracing out three flattened curves. The periodic backwards or retrograde motion [ http://antwrp.gsfc.nasa.gov/apod/ap060422.html ] with respect to the background stars is a reflection of the motion of the Earth itself. Retrograde motion [ http://www.lasalle.edu/~smithsc/Astronomy/ retrograd.html ] can be seen each time Earth overtakes and laps planets orbiting farther from the Sun, the Earth moving more rapidly through its own closer-in [ http://csep10.phys.utk.edu/astr161/lect/retrograde/ copernican.html ] orbit. The Beehive [ http://antwrp.gsfc.nasa.gov/apod/ap060128.html ] star cluster in Cancer lies near the track at the upper right. Stars along the "backward question mark" at the head of Leo [ http://stardate.org/nightsky/constellations/leo.html ] are in the left half of the frame. Saturn's position this month [ http://skytonight.com/observing/home/April_podcast.html ] is near the right hand limit of the middle curve. Click on the picture to download and view the gif animation. |
|
Four Years of Saturn
| Title |
Four Years of Saturn |
| Explanation |
Saturn and [ http://antwrp.gsfc.nasa.gov/apod/ap040117.html ] its magnificent ring system [ http://www2.jpl.nasa.gov/saturn/back.html ] can offer even casual astronomers the most memorable of telescopic sights. Wandering between Leo and Cancer this month [ http://skytonight.com/observing/home/April_podcast.html ], a bright Saturn is [ http://www.nineplanets.org/saturn.html ] well placed for viewing in evening skies [ http://soc.jpl.nasa.gov/viewing.cfm ]. But from our earthbound perspective, the tilt of Saturn's rings does change with time [ http://antwrp.gsfc.nasa.gov/apod/ap030405.html ]. In 1995 and 1996 [ http://hubblesite.org/newscenter/archive/releases/2007/13/ video/a/ ] the broad rings were edge-on and nearly invisible, gradually opening to a spectacular maximum tilt [ http://hubblesite.org/newscenter/archive/releases/2007/13/ video/c/ ] of about 27 degrees by 2003. This frame from a series of Saturn [ http://www.avertedimagination.com/img_pages/ saturn_04_07.html ] images beginning a year later, in 2004, and ending just last month shows the steady decrease in apparent tilt as the rings head toward another edge-on presentation in 2009. Saturn's south pole is toward the bottom. Click on the picture to view the sharp, color gif movie. |
|
Star Cluster Messier 67
| Title |
Star Cluster Messier 67 |
| Explanation |
Gathered [ http://www.seasky.org/cosmic/sky7a06.html ] at the center of this sharp skyview are the stars of Messier 67 [ http://www.seds.org/messier/m/m067.html ], one of the oldest known open star clusters [ http://en.wikipedia.org/wiki/Open_cluster ]. In fact, though open star clusters are usually much younger, the stars of M67 [ http://www.noao.edu/outreach/press/9907.html ] are likely around 4 billion years old, about the same age and with about the same elemental abundances as the Sun. Open clusters are almost always younger [ http://antwrp.gsfc.nasa.gov/apod/ap051118.html ] because they are dispersed over time as they encounter other stars, interstellar clouds, and experience gravitational tides while orbiting [ http://hypertextbook.com/facts/2002/StacyLeong.shtml ] the center of our galaxy. Still, M67 contains over 500 stars or so and lies some 2,800 light-years away in the constellation Cancer [ http://hawastsoc.org/deepsky/cnc/index.html ]. At that estimated distance, M67 would be about 12 light-years across. |
|
55 Cancri: Familiar Planet D
…
| Title |
55 Cancri: Familiar Planet Discovered |
| Explanation |
Is our Solar System [ http://www.nineplanets.org/overview.html ] unique? The discovery of a Jupiter [ http://www.nineplanets.org/jupiter.html ]-like planet in a Jupiter-like orbit around nearby Sun [ http://antwrp.gsfc.nasa.gov/apod/sun.html ]-like star 55 Cancri [ http://www.jtwinc.com/Extrasolar/55Can_Star.html ], announced [ http://www.jpl.nasa.gov/releases/2002/release_2002_133.html ] yesterday, gives a new indication that planetary systems [ http://exoplanets.org/exoplanets_pub.html ] similar to our Solar System [ http://space.jpl.nasa.gov/ ] likely exist elsewhere. The planet, discovered by G. Marcy [ http://astro.berkeley.edu/~gmarcy/ ] (UC Berkeley [ http://astron.berkeley.edu/ ]) and collaborators, is one of two new planets found around 55 Cancri [ http://exoplanets.org/esp/55cnc/55cnc.shtml ] -- in 1997 a Jupiter-massed planet was found orbiting very close in. The finding involved noting subtle changes in the speed [ http://exoplanets.org/doppframe.html ] of the star caused by its orbiting planets. The above drawing depicts what this planet might look like, complete with a hypothetical moon. The star 55 Cancri [ http://www.astro.uiuc.edu/~kaler/sow/55cnc.html ], only 40 light-years distant, is visible [ http://irtf.ifa.hawaii.edu/Science/GalleryOfImages/55cancri.html ] with binoculars [ http://www.birdwatching.com/optics/binoculars1.html ] towards the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Cancer [ http://www.astronomical.org/constellations/cnc.html ]. |
|
Jupiter, Moons and Bees
| Title |
Jupiter, Moons and Bees |
| Explanation |
Rising before the Sun on September 4, Jupiter and an old cresent Moon [ http://antwrp.gsfc.nasa.gov/apod/ap020419.html ] gathered in the dim constellation of Cancer [ http://www.coldwater.k12.mi.us/lms/planetarium/myth/ cancer.html ]. Watching from a hillside near Austin, Texas, planet Earth [ http://earthobservatory.nasa.gov/ ], astrophotographer Russell Croman recorded this view [ http://www.rc-astro.com/solar_system/moon/moonbees.html ] of their passing as clouds gracefully dimmed the brilliant moonlight. Earthshine illuminates [ http://www.amnh.org/exhibitions/codex/2A2r.html ] the lunar night side and on close inspection, bright Jupiter at the lower right appears tightly flanked [ http://antwrp.gsfc.nasa.gov/apod/ap980513.html ] by its own four large Galilean moons [ http://www.jpl.nasa.gov/galileo/ganymede/ discovery.html ]. Next to Jupiter lies a loose swarm of stars just below the clouds. The stars are the brighter members of the nearby star cluster M44, popularly known as the Beehive cluster [ http://antwrp.gsfc.nasa.gov/apod/ap980803.html ]. Croman's remarkable digital image has been processed only slightly to improve the visibility of the earthshine region and Jupiter's moons [ http://antwrp.gsfc.nasa.gov/apod/ap001118.html ]. |
|
Jupiter in the Hive
| Title |
Jupiter in the Hive |
| Explanation |
If you can find planet Jupiter in tonight's sky, then you can also find M44 [ http://www.seds.org/messier/m/m044.html ], popularly known as the Beehive [ http://antwrp.gsfc.nasa.gov/apod/ap020925.html ] star cluster. In fact, with a pair of binoculars most casual skygazers should find it easy to zero in on this celestial scene [ http://www.fourmilab.ch/yoursky/ ]. It should be easy because after sunset Jupiter presently rules the night [ http://stardate.org/nightsky/almanac/ ] as the brightest "star" overhead. Now near the stationary part [ http://www.scienceu.com/observatory/articles/retro/ retro.html ] of its wandering path through the heavens, Jupiter will obligingly linger for a while at a spot only a degree or so southeast of M44 in the relatively faint constellation Cancer [ http://www.coldwater.k12.mi.us/lms/planetarium/myth/ cancer.html ]. Seen here in a photograph from March 28, Jupiter (lower left) is strongly overexposed with the stars of M44 swarming above and to the right. The picture approximately corresponds to the view [ http://www.visualdeepsky.org/netastrocatalog/ msg00123.html ] when looking through a typical pair of binoculars. Jupiter is [ http://galileo.jpl.nasa.gov/jupiter/jupiter.html ] about 30 light-minutes from our fair planet while M44, one of the closest star clusters, is around 600 light-years away. |
|
Comet NEAT and the Beehive C
…
| Title |
Comet NEAT and the Beehive Cluster |
| Explanation |
To the unaided eye, they appeared as similar fuzzy patches. But when a bright comet passed in front of a bright star cluster [ http://antwrp.gsfc.nasa.gov/apod/open_clusters.html ] last month, binoculars and cameras were able to show off their marked differences in dramatic fashion. Pictured above, the bright comet, C/2001 Q4 (NEAT) [ http://www.astronomy.com/Content/Dynamic/Articles/000/000/001/727bsdvn.asp ] shows many details of its coma and tail, while far in the distance the Beehive open cluster, M44 [ http://www.seds.org/messier/m/m044.html ], shows many of its stars. Comet Q4 [ http://skyandtelescope.com/observing/objects/comets/article_1262_1.asp ] has now faded to the edge of unaided visibility and can best be found with a sky map [ http://encke.jpl.nasa.gov/charts.html ] and binoculars from the Northern Hemisphere well into June. Star cluster M44 [ http://antwrp.gsfc.nasa.gov/apod/ap980803.html ] will remain an impressive star cluster toward the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Cancer [ http://www.astronomical.org/portal/modules/wfsection/article.php?articleid=12 ] indefinitely. |
|
An Inner Neptune for 55 Canc
…
| Title |
An Inner Neptune for 55 Cancri |
| Explanation |
Is our Solar System [ http://www.nineplanets.org/overview.html ] unique? The discovery [ http://arXiv.org/abs/astro-ph/0408585 ] of a Neptune [ http://www.nineplanets.org/neptune.html ]-mass planet in an sub-Mercury orbit around nearby Sun [ http://antwrp.gsfc.nasa.gov/apod/sun.html ]-like star 55 Cancri [ http://antwrp.gsfc.nasa.gov/apod/ap020614.html ], announced [ http://planetquest.jpl.nasa.gov/index.html ] yesterday along with the discovery of other similar systems, gives a new indication that planetary systems [ http://exoplanets.org/exoplanets_pub.html ] as complex as our own Solar System [ http://space.jpl.nasa.gov/ ] likely exist elsewhere. The planet, discovered [ http://mcdonaldobservatory.org/news/releases/2004/0831.html ] in data from the Hobby-Eberly telescope [ http://www.as.utexas.edu/mcdonald/het/het.html ] in Texas, the Lick Observatory [ http://www.ucolick.org/ ] in California, and the orbiting Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap010806.html ], is one of four planets now known to orbit 55 Cancri [ http://exoplanets.org/esp/55cnc/55cnc.shtml ] -- the others being similar in mass to Jupiter. The finding involved noting subtle changes in the speed [ http://exoplanets.org/doppframe.html ] of the star caused by its orbiting planets. The above drawing [ http://planetquest.jpl.nasa.gov/news/ssu_images.html ] depicts what this planet might look like, assuming a mass similar to Neptune [ http://antwrp.gsfc.nasa.gov/apod/neptune.html ], but a composition similar [ http://www.solstation.com/stars/4planets.htm ] to Earth. The star 55 Cancri [ http://www.astro.uiuc.edu/~kaler/sow/55cnc.html ], only 40 light-years distant, is visible [ http://irtfweb.ifa.hawaii.edu/Science/GalleryOfImages/55cancri.html ] with binoculars [ http://www.birdwatching.com/optics/binoculars1.html ] towards the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Cancer [ http://www.astronomical.org/portal/modules/wfsection/article.php?articleid=12 ]. |
|
M44: A Beehive of Stars
| Title |
M44: A Beehive of Stars |
| Explanation |
M44 is a prominent open cluster [ http://antwrp.gsfc.nasa.gov/apod/ap970128.html ] of stars. Nicknamed Praesepe and "The Beehive", it is one of the few open clusters [ http://antwrp.gsfc.nasa.gov/apod/ap971018.html ] visible [ http://www.campus.bt.com/CampusWorld/pub/ScienceNet/astron/const/Cancer/m44.html ] to the unaided eye. M44 [ http://antwrp.gsfc.nasa.gov/apod/ap980803.html http://www.seds.org/messier/m/m044.html ] was thought to be a nebula [ http://antwrp.gsfc.nasa.gov/apod/ap980612.html ] until Galileo [ http://antwrp.gsfc.nasa.gov/apod/ap960830.html ] used an early telescope to resolve the cluster's bright blue stars. These stars are visible in the above image [ http://www.psn.net/~airdigital/deepsky_photos_1.html ]. M44 [ http://www.seds.org/messier/more/m044_more.html ], which is thought to have formed about 400 million years ago, is larger and older than most other open clusters [ http://antwrp.gsfc.nasa.gov/apod/index/OpenCluster.html ]. The Beehive Cluster lies about 580 light-years away, and spans about 10 light-years across. When viewed with a powerful telescope, hundreds of stars become visible. |
|
Saturn in the Hive
| Title |
Saturn in the Hive |
| Explanation |
If you can find Saturn [ http://www.spaceweather.com/images2006/27jan06/ skymap_north.gif ] in tonight's sky, then you can also find M44 [ http://www.seds.org/messier/m/m044.html ], popularly known as the Beehive [ http://antwrp.gsfc.nasa.gov/apod/ap020925.html ] star cluster. In fact, with a pair of binoculars most casual skygazers should find it fairly easy to zero in on this celestial scene [ http://skyandtelescope.com/observing/ataglance/ article_110_1.asp ]. Saturn is at opposition [ http://saturn.jpl.nasa.gov/multimedia/images/ image-details.cfm?imageID=1972 ] - opposite the Sun in Earth's sky - so, the bright planet rises in the east at sunset and is visible throughout the night. Near the stationary part [ http://www.scienceu.com/observatory/articles/retro/ retro.html ] of its wandering path through the heavens, Saturn will obligingly linger for a while in the vicinity of M44 in the relatively faint constellation Cancer [ http://www.coldwater.k12.mi.us/lms/planetarium/myth/ cancer.html ]. Seen here in a photograph from January 25, Saturn (lower right) is strongly overexposed with the stars of M44 swarming above and to the left. The picture approximately corresponds to the view [ http://www.visualdeepsky.org/netastrocatalog/ msg00123.html ] when looking through a typical pair of binoculars. Saturn is [ http://nssdc.gsfc.nasa.gov/planetary/planets/ saturnpage.html ] about 64 light-minutes from our fair planet while M44, one of the closest star clusters, is around 600 light-years away. |
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Planets, Bees, and a Donkey
| Title |
Planets, Bees, and a Donkey |
| Explanation |
The heralded alignment of wandering planets Saturn and Mars with the well-known Beehive Cluster [ http://www.seds.org/messier/m/m044.html ] took place last weekend on Saturday, June 17 [ http://antwrp.gsfc.nasa.gov/apod/ap060617.html ]. Recorded in dark Arizona skies on that date, this view finds [ http://www.schursastrophotography.com/10dastro/ satmarsm44.html ] Mars above and right of Saturn - the brightest celestial beacons in the scene - with the Beehive cluster of stars (M44) at the lower right. The two planets appear in conjunction [ http://en.wikipedia.org/wiki/Astronomical_conjunction #Conjunctions_of_planets_in_right_ascension_2005-2020 ] separated by just over half a degree. But about another half a degree along a line joining the two and continuing towards the lower left lies the third brightest object in the image, giant star Asellus Australis. Asellus Australis is also known as Delta Cancri [ http://en.wikipedia.org/wiki/Delta_Cancri ], a middling bright star 136 light-years away in the constellation [ http://www.pa.msu.edu/people/horvatin/Astronomy_Facts/ constellation_pages/cancer.htm ] Cancer, the Crab [ http://www.astro.uiuc.edu/~kaler/sow/cnc-b.html ]. Of course, this star's Latin name [ http://www.pa.msu.edu/people/horvatin/ Astronomy_Facts/star_names.htm ] translates to "Southern Donkey". |
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Remembering Yoram Kaufman: I
…
nasa, nasaimageofthedaygalle
…
Teams for the MISR and CERES
…
yoram_memorial
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-05-26 |
| creator |
NASA -- Photographs and image courtesy NASA |
| identifier |
yoram_memorial |
|
Haze over Eastern China: Nat
…
nasa, nasanaturalhazards
A nearly opaque plume of haz
…
ge_19247
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-10-20 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_19247 |
|
Haze over Eastern China: Nat
…
nasa, nasanaturalhazards
A nearly opaque plume of haz
…
ge_19247
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-10-20 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
ge_19247 |
|
Red Plankton in the Arabian
…
PIA04369
Sol (our sun)
Multi-angle Imaging SpectroR
…
| Title |
Red Plankton in the Arabian Sea |
| Original Caption Released with Image |
. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82° north and 82° south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 25483. The still image panels cover an area of about 240 kilometers x 290 kilometers, and utilize Local Mode data from within blocks 71 to 73 and within World Reference System-2 path 155. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology., In the Arabian Sea, sunlight and nutrients has fueled a startling occurrence of colorful phytoplankton and bacterial assemblages, which is captured in these natural color images from NASA's Multi-angle Imaging SpectroRadiometer (MISR). Several areas exhibit an unmistakably reddish hue, particularly in the upper portion of the images. The image set is centered along the Tropic of Cancer, about 400 kilometers east of Muscat, Oman, and was acquired on October 2, 2004. A view from MISR's nadir (directly downward viewing) camera is provided on the left, while the two smaller images at the upper and lower right are from MISR's 60-degree forward and backward pointing cameras, respectively. The Arabian Sea is an unusual part of the world's oceans because it is surrounded by land masses from three sides, and light levels in the region are strongly influenced by cloud cover generated by the Indian monsoons. Phytoplankton concentrations in the Arabian Sea tend to be highest during September and October, towards the end of the summer monsoon. The offshore drift of surface waters and their replacement by deeper, nutrient-rich waters means that the Arabian Sea is very productive, but such fertilization also sometimes results in copious phytoplankton production and oxygen depletion of the subsurface waters. Although red phytoplankton fluorescences have been associated with the low oxygen concentrations in the intermediate and deep waters of the Arabian Sea, the red pigment in this scene may instead be related to the dynamic processes of plankton grazing and decomposition. Multiple observation angles allow the color of surface ocean waters to be studied in greater detail, and provides a method to observe regions that can not be examined by satellite instruments that view nadir only, in cases where the nadir view is affected by sun glint. In this case, the ocean color in the lower right-hand corner is discernible at 60-degrees backward but not at nadir. Multiple angles also enable the observation of ship and cloud motion. The movement of several ships across the scene is illustrated in an animation. The oblique imagery used in this image set is part of the Local Mode data acquired during the Unified Aerosol Experiment United Arab Emirates (UAE2) field campaign |
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