209458b and HD 189733 and reveal their infrared spectra to Spitzer. Astronomers hope to use Spitzer's spectrograph in the future to study HD 209458b and HD 189733b again in much greater detail, and to examine some of the other candidates for the first time., This artist's concept animation shows a cloudy Jupiter-like planet that orbits very close to its fiery hot star. NASA's Spitzer Space Telescope was recently used to capture spectra, or molecular fingerprints, of two "hot Jupiter" worlds like the one depicted here. This is the first time a spectrum has ever been obtained for an exoplanet, or a planet beyond our solar system. The ground-breaking observations were made with Spitzer's spectrograph, which pries apart infrared light into its basic wavelengths, revealing the "fingerprints" of molecules imprinted inside. Spitzer studied two planets, HD 209458b and HD 189733b, both of which were found, surprisingly, to have no water in the tops of their atmospheres. The results suggest that the hot planets are socked in with dry, high clouds, which are obscuring water that lies underneath. In addition, HD209458b showed hints of silicates, suggesting that the high clouds on that planet contain very fine sand-like particles. Capturing the spectra from the two hot-Jupiter planets was no easy feat. The planets cannot be distinguished from their stars and instead appear to telescopes as single blurs of light. One way to get around this is through what is known as the secondary eclipse technique. In this method, changes in the total light from a so-called transiting planet system are measured as a planet is eclipsed by its star, vanishing from our Earthly point of view. The dip in observed light can then be attributed to the planet alone. This technique, first used by Spitzer in 2005 to directly detect the light from an exoplanet, currently only works at infrared wavelengths, where the differences in brightness between the planet and star are less, and the planet's light is easier to pick out. For example, if the experiment had been done in visible light, the total light from the system would appear to be unchanged, even as the planet disappeared from view. To capture spectra of the planets, Spitzer observed their secondary eclipses with its spectrograph. It took a spectrum of a star together with its planet, then, as the planet disappeared from view, a spectrum of just the star. By subtracting the spectrum of the star from the spectrum of the star and planet together, astronomers were able to determine the spectrum of the planet itself. Neither of the parent stars for HD 209458b or HD 189733b can be seen with the naked eye. HD 209458b is located about 153 light-years away in the constellation Pegasus, while HD 189733b is about 62 light-years away in the constellation Vulpecula. Both planets zip around their stars in very tight orbits, HD 209458b circles once every 3.5 days, while HD 189733b orbits once every 2.2 days. Of the approximately 200 known exoplanets, there are 12 besides HD 209458b and HD 189733b whose orbits are inclined in such a way that, from our point of view, they pass in front of their stars. At least three of these transiting exoplanets are bright enough to follow in the footsteps of HD
Monkey Baker with a Model Ju
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Name of Image
Monkey Baker with a Model Jupiter Vehicle
Date of Image
1959-05-29
Full Description
Monkey Baker, payload of Jupiter (AM-18), poses on a model of the Jupiter vehicle, May 29, 1959
PROJECT MERCURY - LITTLE JOE
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Title
PROJECT MERCURY - LITTLE JOE TEST - SAM LAUNCHED USING A RHESUS MONKEY
KENNEDY SPACE CENTER, FLA. -
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Description
KENNEDY SPACE CENTER, FLA. -- This adult bald eagle rests on the ground near a pond close to S.R. 3 in NASA's Kennedy Space Center. Bald eagles live near large bodies of open water such as lakes, marshes, seacoasts and rivers, where there are plenty of fish to eat and tall trees for nesting and roosting. Bald eagles feed primarily on fish, but also eat small animals (ducks, coots, muskrats, turtles, rabbits, snakes, etc.) and occasional carrion (dead animals). They are sometimes seen among a gathering of vultures at the site of a fresh meal. Bald eagles have a presence in every U. S. state except Hawaii. Bald eagles use a specific territory for nesting (they mate for life), winter feeding or a year-round residence. Its natural domain is from Alaska to Baja, California, and from Maine to Florida. There are a dozen eagle nests both in KSC and in the Merritt Island National Wildlife Refuge, which surrounds KSC. The refuge includes several wading bird rookeries, many osprey nests, up to 400 manatees during the spring, and approximately 2,500 Florida scrub jays. It also is a major wintering area for migratory birds. More than 500 species of wildlife inhabit the refuge, with 15 considered federally threatened or endangered. Photo credit: NASA/George Shelton
Release Date
04/20/2007
Record Snow in California
Title
Record Snow in California
Description
A powerful Alaskan storm swept over California during the final week of October, drenching the state with record rain and snow. The storm was the second large storm to move over California in as many weeks, and it left the Sierra Nevada Mountains coated in snow. In this Moderate Resolution Imaging Spectroradiometer (MODIS [ http://modis.gsfc.nasa.gov ]) image, taken by NASA's Terra [ http://terra.nasa.gov/ ] satellite on October 31, 2004, after the clouds cleared, snow highlights the peaks of the long mountain chain that forms California's eastern border with Nevada. According to the Associated Press, the central Sierra Nevada received as much as 48 inches (1.2 meters) of snow in October, allowing ski resorts to open earlier than normal. Ski resort owners are not the only people who are pleased with the snowfall?California relies heavily on melting snow for its water supply. Like much of the west, California has been in drought for the past six years, and while this snowfall alone is not enough to end the drought, it will help. At the end of October, many locations in California had set new records for monthly rain or snowfall totals. The snow extends all the way down the 400-mile length of the Sierra Nevada Mountains in this image. On October 30, MODIS captured an image [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=12560 ] of snow even further south in the San Bernardino Mountains around Los Angeles. NASA image created by Jesse Allen, Earth Observatory, using data obtained from the MODIS Rapid Response team.
Aurora Over Iowa
Title
Aurora Over Iowa
Explanation
Last Thursday evening, stars were not the only lights in Iowa skies. Spectacular northern lights [ http://www.exploratorium.edu/learning_studio/auroras/ ] also shone from the heavens, extending across the midwestern USA and other locations [ http://spaceweather.com/aurora/gallery_01dec06_page3.htm ] not often graced with auroral displays. The wide-ranging auroral activity was triggered as a large solar flare [ http://sohowww.nascom.nasa.gov/pickoftheweek/ ] - an energetic cloud of particles blasted outward from the Sun [ http://antwrp.gsfc.nasa.gov/apod/sun.html ] a few days earlier - collided with planet Earth's [ http://www-istp.gsfc.nasa.gov/istp/outreach/geospace.html ] magnetosphere. Alerted to [ http://spaceweather.com/ ] conditions ripe for aurora [ http://antwrp.gsfc.nasa.gov/apod/ap060329.html ], photographer Stan Richard recorded this apparition [ http://www.nightskyevents.com/events_in_the_night_sky_main.htm ] over Saylorville Lake [ http://en.wikipedia.org/wiki/Saylorville_Lake ], near Des Moines [ http://en.wikipedia.org/wiki/Des_Moines%2C_Iowa ], Iowa [ http://en.wikipedia.org/wiki/Iowa ], USA [ https://cia.gov/cia//publications/factbook/geos/us.html ]. While the colorful rays seem to end just above the water, they are actually at altitudes of 100 kilometers or more [ http://antwrp.gsfc.nasa.gov/apod/ap010210.html ].
Mount Megantic Magnetic Stor
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Title
Mount Megantic Magnetic Storm
Explanation
Plasma from the Sun and debris from a comet both collided with planet Earth last Saturday morning triggering magnetic storms [ http://www.sec.noaa.gov/NOAAscales/ ] and a meteor shower in a dazzling atmospheric spectacle [ http://spacescience.com/headlines/y2000/ ast14aug_1.htm ]. The debris stream from comet Swift-Tuttle is anticipated [ http://antwrp.gsfc.nasa.gov/apod/ap000812.html ] yearly, and many skygazers [ http://www.imo.net/news/news.html ] already planned to watch the peak of the annual Perseids [ http://comets.amsmeteors.org/meteors/showers/ perseids.html ] meteor shower in the dark hours of August 11/12. But the simultaneous, widely reported [ http://www.globaldialog.com/~jrummel/Aurora/ Aurora.html ] auroras were [ http://www.infowest.com/personal/s/schmutz/ aurora.HTML ] triggered by the chance arrival of something much less predictable -- a solar coronal mass ejection [ http://science.nasa.gov/ssl/pad/solar/ cmes.htm ]. This massive bubble of energetic plasma was seen leaving the active Sun's surface on August 9, just in time to travel to Earth and disrupt the planet's magnetic field [ http://www-spof.gsfc.nasa.gov/Education/ Intro.html ] triggering extensive auroras [ http://antwrp.gsfc.nasa.gov/cgi-bin/apod/ apod_ts?aurora ] during the meteor shower's peak! Inspired by the cosmic light show, Sebastien Gauthier photographed the [ http://www.geocities.com/CapeCanaveral/Station/3622/ AlbumPhotoAstronomie/AlbumAstronomie3.htm ] colorful auroral displays above the dramatic dome of the Mount-Megantic [ http://astrolab.interlinx.qc.ca/ ] Popular Observatory [ http://astrolab.interlinx.qc.ca/Obs_pop/ OPMM/ob_pop_choix.htm ] in southern Quebec, Canada. Bright Jupiter and giant star Aldebaran can be seen peering through [ http://antwrp.gsfc.nasa.gov/apod/ap000504.html ] the shimmering northern lights at the upper right.
Ultraviolet Movie of Jupiter
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Title
Ultraviolet Movie of Jupiter's Polar Stratosphere
Description
Cassini imaging team home page,http://ciclops.lpl.arizona.edu [ http://ciclops.lpl.arizona.edu ]. The imaging team is based at the Boulder, Colo., campus of the Southwest Research Institute. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C., Unexpected dynamics in Jupiter's upper atmosphere, or stratosphere, including the birth and motion of a dark vortex wider than Earth, appear in amovie clipspanning 11 weeks of ultraviolet imaging by NASA's Cassini spacecraft. The development of the vortex resembles development of ozone holes in Earth's stratosphere in that both processes appear to occur only within confined masses of high-altitude polar air. That similarity may help scientists understand both processes better. The movie is the first from any spacecraft to examine the planet's churning atmosphere in ultraviolet wavelengths. Hydrocarbons in Jupiter's stratosphere are transparent at the longer wavelengths of visible light and infrared light, but appear as haze in ultraviolet light. Cassini's narrow-angle camera took images from a near-equatorial perspective as the spacecraft approached Jupiter from Oct. 1, 2000, to Dec. 15, 2000. The images have been combined and re-projected into a movie view as if looking down on Jupiter's north pole. Contrast was enhanced to reveal faint features. The view extends south to the equator at the corners of the frame. The black dot right at the pole is where no presentable data were acquired, due to Cassini's viewing angle. For reference, a circle of 60 degrees latitude is superimposed in white, and an oval where Jupiter has a persistent aurora is superimposed in blue. The aurora itself, comparable to Earth's Northern Lights, is not visible here. Energetic auroras heat the stratosphere and stimulate the formation of complex hydrocarbons from the breakup of methane molecules. A dark patch appears and within two weeks becomes a well-defined oval about the same size and shape as Jupiter's southern hemisphere Great Red Spot. While this dark vortex is nestled inside the auroral oval, its outer edge begins to circulate in a clockwise direction and it develops a small, brighter, inner core. It eventually moves out of the auroral region and deforms by flattening in latitude and growing in longitude. Near the end of the movie, a second, smaller, dark oval appears nearer to the pole and deforms in the wind shear. A series of wave features rings the planet south of (outside of) the latitude-60 circle. These make visible some of the dynamics of how haze generated in the confined polar stratosphere mixes eventually into the winds farther south. Comparison of this ultraviolet movie with a near-infrared movie that was produced the same way and released previously (PIA-03452) reveals many differences. Instead of the waves and large vortex seen in the ultraviolet, the infrared imaging shows a multitude of small storms and parallel wind bands at a lower elevation in the atmosphere. Cassini made its closest pass to Jupiter, about 10 million kilometers (6 million miles), on Dec. 30, 2000, and proceeded toward its ultimate destination at Saturn. For more information, see the Cassini Project home page,http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov ]and the
Date
05.31.2000
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