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Dawn of Goddard Space Flight Center (GSFC) and Washington, D.C.
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Phoebe's Radiation
| Description |
Phoebe's Radiation |
| Full Description |
This image shows thermal radiation from the day and night sides of Saturn's moon Phoebe, taken by the composite infrared spectrometer onboard Cassini 1.8 hours before the spacecraft's closest approach to Phoebe on June 11, 2004. The left-hand panel displays the image in grayscale format, showing the brightness of Phoebe's radiation in the wavelength range 15-17 microns, which is about 25 times the longest wavelength visible to the naked eye. In the middle panel this brightness is used to estimate the surface temperature distribution across Phoebe. Temperatures are given in degrees Kelvin, and vary from a relatively toasty 107 Kelvin (-267 Fahrenheit), in the late morning near the equator (white, lower right), to less than 75 Kelvin (-324 Fahrenheit) in the northern hemisphere in the pre-dawn hours (dark blue, upper left). The "ragged edge" of Phoebe in this region is an instrumental artifact. Temperatures are affected strongly by topography, as can be seen by comparison with the visible-wavelength image (right). Some of the coldest temperatures are found in the shadowed region inside the large depression in the northern hemisphere (upper right). The Cassini-Huygens mission 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-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini composite infrared spectrometer home page at http://cirs.gsfc.nasa.gov/ . Image Credit: NASA/JPL/Goddard Space Flight Center |
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Phoebe Temperature Maps
| Description |
Phoebe Temperature Maps |
| Full Description |
A montage of maps of Saturn's moon Phoebe shows surface temperatures at various times of day as determined by the composite infrared spectrometer onboard Cassini during the June 11, 2004, Phoebe flyby. The asterisk on each map shows the location of the subsolar point, where the Sun is directly overhead. This point moves across the surface as Phoebe rotates. It is morning in regions to the left of the subsolar point, and afternoon in regions to the right. Like a newspaper weather map, different colors indicate different temperatures, though Phoebe's temperatures are distinctly cooler than even the coldest January day on Earth. Equatorial temperatures peak in the early afternoon near 112 Kelvin (-257 Fahrenheit), plunging to 78 Kelvin (-319 Fahrenheit) before dawn, and are even colder at higher latitudes. The large day/night temperature contrasts imply that Phoebe's surface is covered in loose dust or ice particles that store little heat and thus cool off rapidly at night. Regions of Phoebe's surface that were not observed are shown in black. Most of the maps show the effect on surface temperatures of the large crater-like depression seen in Cassini's visible-wavelength images of Phoebe, which is located just left of center in these maps. Crater walls that are shadowed and cold in the early morning in the first map are sunlit and warm in the late afternoon in the final map. The Cassini-Huygens mission 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-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini composite infrared spectrometer home page at http://cirs.gsfc.nasa.gov/ . Image Credit: NASA/JPL/Goddard Space Flight Center |
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Moon And Venus Share The Sky
| Title |
Moon And Venus Share The Sky |
| Explanation |
July is drawing to a close and in the past few days, some early morning risers [ http://antwrp.gsfc.nasa.gov/apod/ap990714.html ] could have looked east and seen a crescent Moon sharing the pre-dawn [ http://science.nasa.gov/headlines/y2000/ast25jul_1m.htm ] skies with planets Jupiter and Saturn. Planet Mercury will also pass about 2 degrees from the thin waning crescent Moon [ http://aa.usno.navy.mil/AA/faq/docs/moon_phases.html ] just before sunrise near the eastern horizon on Saturday, July 29. And finally, on the evening of July 31st, Venus will take its turn near the crescent Moon [ http://antwrp.gsfc.nasa.gov/apod/ap991108.html ]. But this time it will be a day-old crescent Moon near the western horizon, shortly after sunset [ http://antwrp.gsfc.nasa.gov/apod/ap000507.html ]. In fact [ http://pages.prodigy.net/pam.orman/JoeAlmanac2000.html ], on July 31 (August 1 Universal Time) the Moon will occult [ http://www.skypub.com/sights/occultations/lunar/ 0001lunarocc.html ] (pass in front of) Venus for northwestern observers [ http://www.skypub.com/sights/images2000/ 0008moonvenus_big.jpg ] in North America. This telescopic picture taken on 31 December 1997, shows a lovely young crescent Moon and brilliant crescent Venus in [ http://antwrp.gsfc.nasa.gov/apod/ap990903.html ] the early evening sky near Bursa, Turkey [ http://www.mersina.com/Turkey/Marmara/Bursa/index.html ]. And what about the Sun? On Sunday, July 30, a partial eclipse of the Sun [ http://sunearth.gsfc.nasa.gov/eclipse/extra/ PSE2000Jul31.html ] will be visible from some locations [ http://sunearth.gsfc.nasa.gov/eclipse/OH/ PSE2000Jul.gif ] in North America. |
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NGC 6960: The Witch's Broom
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| Title |
NGC 6960: The Witch's Broom Nebula |
| Explanation |
Ten thousand years ago, before the dawn of recorded human history [ http://news.bbc.co.uk/hi/english/sci/tech/newsid_334000/334517.stm ], a new light must suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was an exploding star [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/supernovae.html ] and record the colorful expanding cloud as the Veil Nebula [ http://nineplanets.org/twn/cygnusx.html ]. Pictured above [ http://robgendler.astrodigitals.com/Nebulas.html ] is the west end of the Veil Nebula [ http://www.astropix.com/HTML/E_SUM_N/VEIL.HTM ] known technically as NGC [ http://www.ngcic.com/dss/dss_images.htm ] 6960 but less formally as the Witch's Broom Nebula. The rampaging gas gains its colors by impacting and exciting existing [ http://antwrp.gsfc.nasa.gov/apod/ap960307.html ] nearby gas. The supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ] lies about 1400 light-years away towards the constellation of Cygnus [ http://www.multimania.com/cdadfs/constellation/cygne/cygnus.htm ]. This Witch's Broom actually spans over three times the angular size of the full Moon [ http://antwrp.gsfc.nasa.gov/apod/moon.html ]. The bright blue star 52 Cygnus [ http://www.seds.org/Maps/Stars_en/Fig/cygnus.html ] is visible with the unaided eye from a dark location but unrelated to the ancient supernova [ http://www.chapman.edu/oca/benet/intro_sn.htm ]. |
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NGC 6960: The Witch's Broom
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| Title |
NGC 6960: The Witch's Broom Nebula |
| Explanation |
Ten thousand years ago, before the dawn of recorded human history [ http://news.bbc.co.uk/hi/english/sci/tech/newsid_334000/334517.stm ], a new light must suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was an exploding star [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/supernovae.html ] and record the colorful expanding cloud as the Veil Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap010928.html ]. Pictured above [ http://www.noao.edu/image_gallery/html/im0852.html ] is the west end of the Veil Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap030204.html ] known technically as NGC [ http://en.wikipedia.org/wiki/New_General_Catalog ] 6960 but less formally as the Witch [ http://antwrp.gsfc.nasa.gov/apod/ap061211.html ]'s Broom [ http://www.broomshop.com/history/ ] Nebula. The rampaging gas gains its colors by impacting and exciting existing [ http://www.seds.org/billa/twn/cygnusx.html ] nearby gas. The supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ] lies about 1400 light-years [ http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html ] away towards the constellation of Cygnus [ http://www.multimania.com/cdadfs/constellation/cygne/cygnus.htm ]. This Witch's Broom actually spans over three times the angular size [ http://imagine.gsfc.nasa.gov/YBA/HTCas-size/more-ang_size.html ] of the full Moon [ http://antwrp.gsfc.nasa.gov/apod/ap030810.html ]. The bright star 52 Cygnus [ http://www.seds.org/Maps/Stars_en/Fig/cygnus.html ] is visible with the unaided eye from a dark location but unrelated to the ancient supernova [ http://en.wikipedia.org/wiki/Supernova ]. |
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Venus' Evening Loop
| Title |
Venus' Evening Loop |
| Explanation |
From September 2000 through March 2001, astronomer Tunc Tezel patiently photographed the planet Venus on 25 different dates as it wandered [ http://zebu.uoregon.edu/~js/ast221/lectures/ lec06.html ] through the evening twilight. The pictures were taken from the same spot on the campus of the Middle East Technical University near Ankara, Turkey, and timed so that for each photo the Sun was [ http://aa.usno.navy.mil/data/docs/RS_OneYear.html ] 7 degrees below the horizon. Carefully registering and combining the pictures, he produced this composite image -- a stunning demonstration of Venus' grand [ http://stoner.eps.mcgill.ca/~bud/craters/ FaceOfVenus.html ] looping sky motion [ http://sunra.colorado.edu/david/ch1.html ] during its recent stint as planet Earth's evening star [ http://www.library.utoronto.ca/utel/rp/poems/ longfe10.html ]. As indicated, the first picture, taken September 28, 2000, finds Venus [ http://www.windows.ucar.edu/cgi-bin/tour_def/venus/ morning_star.html ] close to the western horizon [ http://antwrp.gsfc.nasa.gov/apod/ap990619.html ] and drifting south (left) with the passing days. By December however, Venus [ http://nssdc.gsfc.nasa.gov/planetary/planets/ venuspage.html ] was climbing well above the horizon after sunset and in January 2001 it reached its maximum apparent distance (elongation [ http://astrosun.tn.cornell.edu/courses/astro201/ planet_view.htm ]) from the Sun. March found Venus [ http://antwrp.gsfc.nasa.gov/apod/ap010308.html ] falling from the evening sky while moving rapidly north, finally appearing (far right) as a faint dot against the sunset glow on March 24. This month, Venus rises before dawn as the brilliant morning star [ http://stardate.utexas.edu/resources/ faqs/049.html ]. |
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NGC 6960: The Witch's Broom
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| Title |
NGC 6960: The Witch's Broom Nebula |
| Explanation |
Ten thousand years ago, before the dawn of recorded human history [ http://news.bbc.co.uk/hi/english/sci/tech/newsid_334000/334517.stm ], a new light must suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was an exploding star [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/supernovae.html ] and record the colorful expanding cloud as the Veil Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap010928.html ]. Pictured above [ http://starryscapes.com/nebula/ngc6960.html ] is the west end of the Veil Nebula [ http://www.astropix.com/HTML/E_SUM_N/VEIL.HTM ] known technically as NGC [ http://www.ngcic.com/dss/dss_images.htm ] 6960 but less formally as the Witch's Broom Nebula. The rampaging gas gains its colors by impacting and exciting existing [ http://www.seds.org/billa/twn/cygnusx.html ] nearby gas. The supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ] lies about 1400 light-years [ http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html ] away towards the constellation of Cygnus [ http://www.multimania.com/cdadfs/constellation/cygne/cygnus.htm ]. This Witch's Broom actually spans over three times the angular size [ http://imagine.gsfc.nasa.gov/YBA/HTCas-size/more-ang_size.html ] of the full Moon [ http://antwrp.gsfc.nasa.gov/apod/moon.html ]. The bright blue star 52 Cygnus [ http://www.seds.org/Maps/Stars_en/Fig/cygnus.html ] is visible with the unaided eye from a dark location but unrelated to the ancient supernova [ http://www.chapman.edu/oca/benet/intro_sn.htm ]. |
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Wisps of the Veil Nebula
| Title |
Wisps of the Veil Nebula |
| Explanation |
These wisps of gas are all that remain visible of a Milky Way [ http://www.seds.org/messier/more/mw.html ] star. Many thousands of years ago that star exploded in a supernova [ http://heasarc.gsfc.nasa.gov/docs/snr.html ] leaving the Veil Nebula [ http://www.skyhound.com/sh/archive/aug1/NGC_6960.html ], pictured above [ http://www.astropix.com/HTML/E_SUM_N/VEIL.HTM ]. At the time, the expanding cloud [ http://antwrp.gsfc.nasa.gov/apod/ap010928.html ] was likely as bright as a crescent Moon [ http://antwrp.gsfc.nasa.gov/apod/ap010218.html ] toward the constellation [ http://www.dibonsmith.com/constel.htm ] of Cygnus [ http://www.dibonsmith.com/cyg_con.htm ], visible for weeks to people living at the dawn of recorded history [ http://news.bbc.co.uk/1/hi/sci/tech/334517.stm ]. The remaining supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ] lies about 1400 light-years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] away and covers over five times the size of the full Moon [ http://antwrp.gsfc.nasa.gov/apod/ap020316.html ]. The bright wisp on the right is known as the Witch's Broom Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap030101.html ] and can be seen with a small telescope. The Veil Nebula [ http://www.lfc.edu/~daidoje/ ] is also known as the Cygnus Loop [ http://antwrp.gsfc.nasa.gov/apod/ap010623.html ]. |
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NGC 6960: The Witch's Broom
…
| Title |
NGC 6960: The Witch's Broom Nebula |
| Explanation |
Ten thousand years ago, before the dawn of recorded human history [ http://news.bbc.co.uk/hi/english/sci/tech/newsid_334000/334517.stm ], a new light must suddenly have appeared in the night sky and faded after a few weeks. Today we know this light was an exploding star [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/supernovae.html ] and record the colorful expanding cloud as the Veil Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap010928.html ]. Pictured above [ http://www.noao.edu/image_gallery/html/im0852.html ] is the west end of the Veil Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap030204.html ] known technically as NGC [ http://www.ngcic.com/dss/dss_images.htm ] 6960 but less formally as the Witch [ http://antwrp.gsfc.nasa.gov/apod/ap031229.html ]'s Broom [ http://www.broomshop.com/history/ ] Nebula. The rampaging gas gains its colors by impacting and exciting existing [ http://www.seds.org/billa/twn/cygnusx.html ] nearby gas. The supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ] lies about 1400 light-years [ http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html ] away towards the constellation of Cygnus [ http://www.multimania.com/cdadfs/constellation/cygne/cygnus.htm ]. This Witch's Broom actually spans over three times the angular size [ http://imagine.gsfc.nasa.gov/YBA/HTCas-size/more-ang_size.html ] of the full Moon [ http://antwrp.gsfc.nasa.gov/apod/ap030810.html ]. The bright star 52 Cygnus [ http://www.seds.org/Maps/Stars_en/Fig/cygnus.html ] is visible with the unaided eye from a dark location but unrelated to the ancient supernova [ http://www.chapman.edu/oca/benet/intro_sn.htm ]. |
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A Perseid Meteor
| Title |
A Perseid Meteor |
| Explanation |
The ongoing Perseid Meteor Shower [ http://science.nasa.gov/headlines/y2004/25jun_perseids2004.htm ] should be at its strongest tonight and tomorrow night. Although meteors [ http://www.planetary.org/learn/activities/meteorshowers.html ] should be visible all night long, the best time to watch will be between 2:00 AM and dawn [ http://antwrp.gsfc.nasa.gov/apod/ap040811.html http://www.thursdaysclassroom.com/31jul01/teach2.html ] each night. In dark, moonless, predawn skies [ http://antwrp.gsfc.nasa.gov/apod/ap020809.html ] you may see dozens of meteors per hour. Sky enthusiasts [ http://antwrp.gsfc.nasa.gov/apod/ap040808.html ] in Europe and Asia might see an unusual burst of meteors near 2100 hours UT [ http://aa.usno.navy.mil/faq/docs/UT.html ]. Grains [ http://antwrp.gsfc.nasa.gov/apod/ap001117.html ] of cosmic sand and gravel shed from Comet Swift-Tuttle [ http://antwrp.gsfc.nasa.gov/apod/ap960219.html ] will streak across the sky as they vaporize during entry into Earth's atmosphere. Tracing the meteor trails backwards, experienced skygazers [ http://antwrp.gsfc.nasa.gov/apod/ap010810.html ] will find they converge on the constellation Perseus, thus this annual [ http://www.spaceweather.com/meteors/ gallery_13aug01.html ] meteor shower's name. Pictured above [ http://astropics.com/perseids/081202.htm ] is a Perseid meteor from 2002 over a rock formation in the US Southwest desert. Shadowing and blurring are caused by the long 10-minute exposure. The brightest Perseids can be seen from anywhere on Earth by monitoring the continuously returning images from the Night Sky Live [ http://nightskylive.net/ ] cameras. |
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Moon, Planets, and Rocket Tr
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| Title |
Moon, Planets, and Rocket Trails |
| Explanation |
Are you an early riser [ http://redfrog.norconnect.no/~poems/poems/09560.html ]? Over the last month or so, the bright planets [ http://antwrp.gsfc.nasa.gov/apod/ap990325.html ] Jupiter and Saturn have come to adorn eastern skies before sunrise [ http://redfrog.norconnect.no/~poems/poems/17572.html ]. In fact, astrophotographer Joe Orman [ http://home.cwix.com/~pam.orman@cwix.com/JoeGallery.html ] anticipated that an early bird's reward for looking east on June 10 would be this pleasing arrangement of Jupiter (top right), a crescent Moon, and Saturn (near center), but he was surprised to also find these eerie, iridescent clouds wafting through the pre-dawn sky over suburban Phoenix, Arizona, USA. The clouds turned out to be rocket [ http://www-istp.gsfc.nasa.gov/stargaze/Srockhis.htm ] engine [ http://www.wff.nasa.gov/ ] trails [ ftp://pao.gsfc.nasa.gov/pub/PAO/Releases/1999/W99-013.htm ] from defense missile tests at the range in White Sands [ http://ruidoso.net/chamber/outdoors/whitesan.html ], New Mexico ... about 300 miles away. While the Moon's phase [ http://aa.usno.navy.mil/AA/data/docs/MoonPhase.html#ninetynine ] is just past new moon [ http://lunar.arc.nasa.gov/history/mythologyh.html ], gone now from the pre-dawn horizon, brilliant Jupiter [ http://galileo.ivv.nasa.gov/ ] and Saturn [ http://www.jpl.nasa.gov/cassini/ ] can still be seen high toward the southeast in the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/ constellations.html ] Aries. |
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The Veil Nebula Unveiled
| Title |
The Veil Nebula Unveiled |
| Explanation |
These wisps of gas are all that remain visible of a Milky Way [ http://www.seds.org/messier/more/mw.html ] star. Many thousands of years ago that star exploded in a supernova [ http://heasarc.gsfc.nasa.gov/docs/snr.html ] leaving the Veil Nebula [ http://www.skyhound.com/sh/archive/aug1/NGC_6960.html ], pictured above [ http://www.leif.org/mikael/veil.html ]. At the time, the expanding cloud [ http://antwrp.gsfc.nasa.gov/apod/ap010928.html ] was likely as bright as a crescent Moon [ http://antwrp.gsfc.nasa.gov/apod/ap051113.html ] toward the constellation [ http://www.dibonsmith.com/constel.htm ] of Cygnus [ http://www.dibonsmith.com/cyg_con.htm ], visible for weeks to people living at the dawn of recorded history [ http://news.bbc.co.uk/1/hi/sci/tech/334517.stm ]. The supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/supernova_remnants.html ] lies about 1400 light-years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] away and covers over five times the size of the full Moon [ http://antwrp.gsfc.nasa.gov/apod/ap020316.html ]. The above image [ http://www.leif.org/mikael/veil.html ] of the Veil [ http://en.wikipedia.org/wiki/Veil ] was made clearer by digitally dimming stars in the frame. The bright wisp at the top is known as the Witch's Broom Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap030101.html ] and can be seen with a small telescope. The Veil Nebula [ http://antwrp.gsfc.nasa.gov/cgi-bin/apod/ apod_search?veil+nebula ] is also known as the Cygnus Loop [ http://antwrp.gsfc.nasa.gov/apod/ap010623.html ]. |
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Phoebe Temperature Maps
PIA06403
Saturn
Composite Infrared Spectrome
…
| Title |
Phoebe Temperature Maps |
| Original Caption Released with Image |
A montage of maps of Saturn's moon Phoebe shows surface temperatures at various times of day as determined by the composite infrared spectrometer onboard Cassini during the June 11, 2004, Phoebe flyby. The asterisk on each map shows the location of the subsolar point, where the Sun is directly overhead. This point moves across the surface as Phoebe rotates. It is morning in regions to the left of the subsolar point, and afternoon in regions to the right. Like a newspaper weather map, different colors indicate different temperatures, though Phoebe's temperatures are distinctly cooler than even the coldest January day on Earth. Equatorial temperatures peak in the early afternoon near 112 Kelvin (-257 Fahrenheit), plunging to 78 Kelvin (-319 Fahrenheit) before dawn, and are even colder at higher latitudes. The large day/night temperature contrasts imply that Phoebe's surface is covered in loose dust or ice particles that store little heat and thus cool off rapidly at night. Regions of Phoebe's surface that were not observed are shown in black. Most of the maps show the effect on surface temperatures of the large crater-like depression seen in Cassini's visible-wavelength images of Phoebe, which is located just left of center in these maps. Crater walls that are shadowed and cold in the early morning in the first map are sunlit and warm in the late afternoon in the final map. The Cassini-Huygens mission 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-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov/ ] and the Cassini imaging team home page, http//cirs.gsfc.nasa.gov/ [ http://cirs.gsfc.nasa.gov/ ]. |
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Phoebe's Radiation
PIA06402
Saturn
Composite Infrared Spectrome
…
| Title |
Phoebe's Radiation |
| Original Caption Released with Image |
This image shows thermal radiation from the day and night sides of Saturn's moon Phoebe, taken by the composite infrared spectrometer onboard Cassini 1.8 hours before the spacecraft's closest approach to Phoebe on June 11, 2004. The left-hand panel displays the image in grayscale format, showing the brightness of Phoebe's radiation in the wavelength range 15-17 microns, which is about 25 times the longest wavelength visible to the naked eye. In the middle panel this brightness is used to estimate the surface temperature distribution across Phoebe. Temperatures are given in degrees Kelvin, and vary from a relatively toasty 107 Kelvin (-267 Fahrenheit), in the late morning near the equator (white, lower right), to less than 75 Kelvin (-324 Fahrenheit) in the northern hemisphere in the pre-dawn hours (dark blue, upper left). The "ragged edge" of Phoebe in this region is an instrumental artifact. Temperatures are affected strongly by topography, as can be seen by comparison with the visible-wavelength image (right). Some of the coldest temperatures are found in the shadowed region inside the large depression in the northern hemisphere (upper right). The Cassini-Huygens mission 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-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov/ ] and the Cassini imaging team home page, http//cirs.gsfc.nasa.gov/ [ http://cirs.gsfc.nasa.gov/ ]. |
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