Search Results: All Fields similar to 'Sun or Mercury or Venus or Mars or Jupiter or Saturn or Or or Uranus or Neptune or Pluto' and What equal to 'Moon'

Printer Friendly
1 2 3 489 90
1-50 of 4,472
     
     
Solar System Montage
Title Solar System Montage
Full Description This is a montage of planetary images taken by spacecraft managed by the Jet Propulsion Laboratory in Pasadena, CA. Included are (from top to bottom) images of Mercury, Venus, Earth (and Moon), Mars, Jupiter, Saturn, Uranus and Neptune. The spacecraft responsible for these images are as follows: the Mercury image was taken by Mariner 10, the Venus image by Magellan, the Earth image by Galileo, the Mars image by Viking, and the Jupiter, Saturn, Uranus and Neptune images by Voyager. Pluto is not shown as no spacecraft has yet visited it. The inner planets (Mercury, Venus, Earth, Moon, and Mars) are roughly to scale to each other, the outer planets (Jupiter, Saturn, Uranus, and Neptune) are roughly to scale to each other. Actual diameters are given below: Sun 1,390,000 km Mercury 4,879 km Venus 12,104 km Earth 12,756 km Moon 3,475 km Mars 6,794 km Jupiter 142.984 km Saturn 120,536 km Uranus 51,118 km Neptune 49,528 km Pluto 2,390 km
Date 04/09/1999
NASA Center Jet Propulsion Laboratory
Solar System Montage
Title Solar System Montage
Description This is a montage of planetary images taken by spacecraft managed by the Jet Propulsion Laboratory in Pasadena, CA. Included are (from top to bottom) images of Mercury, Venus, Earth (and Moon), Mars, Jupiter, Saturn, Uranus and Neptune. The spacecraft responsible for these images are as follows: the Mercury image was taken by Mariner 10, the Venus image by Magellan, the Earth image by Galileo, the Mars image by Viking, and the Jupiter, Saturn, Uranus and Neptune images by Voyager.
Date 02.01.1996
A Sky Full Of Planets
Title A Sky Full Of Planets
Explanation Look up tonight [ http://www.cnn.com/TECH/9712/01/heavenly.show.ap/ ]. Just after sunset, the crescent moon and all five "naked-eye" planets (Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap971130.html ], Venus [ http://antwrp.gsfc.nasa.gov/apod/ap971014.html ], Mars [ http://antwrp.gsfc.nasa.gov/apod/ap970528.html ], Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap971030.html ], and Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap970829.html ]) will be visible (depending on your latitude), lying near our solar system's ecliptic plane [ http://antwrp.gsfc.nasa.gov/apod/ap970927.html ]. Venus and Jupiter will shine brilliantly as the brightest "stars" in the sky, but Mercury will be near the horizon and hard to see. A pair of binoculars will also reveal Uranus and Neptune and observers with a telescope and a good site may even be able to glimpse faint Pluto just above the Western horizon in the fading twilight (not shown on the chart above). Enjoy this lovely spectacle any clear night [ http://www.skypub.com/whatsup/dec97sky.html ] through about December 8. A similar gathering is expected in May 2000 [ http://www.skypub.com/special/alignmnt/whypanic.html ] but the planets will be hidden from view by the solar glare. A night sky as full of planets as this one will occur again though ... in about 100 years.
Moons of the Solar System
title Moons of the Solar System
description All the planetary moons in our solar system are shown here at their correct relative size and true color. Their diversity of size and appearance is testament to the unique and fascinating geologic history that each of these bodies has undergone. Two of the moons are larger than the planet Mercury, and eight of them are larger than Pluto. Earth's Moon is the fifth largest of the set, with a diameter of 3476 kilometers (2160 miles). Most of the moons are thought to have formed from a disk of debris left over from formation of the planet they orbit. However Triton, Neptune's largest moon, and several of the smallest moons, including the moons of Mars, are thought to be captured planetesimals that formed elsewhere in the solar system. Earth's Moon is thought to have formed from the debris ejected from a roughly Mars-sized object colliding with the early Earth, perhaps a unique event in the history of the solar system. The moons are organized on the diagram by the planet they orbit (top to bottom with increasing distance from the Sun) and their position relative to the planet (left to right with increasing distance from the planet). Below is a listing of the names of all the moons and the planets they orbit. Most moons are named for mythological characters associated with the character the planet is named for. While most of the planets are named for Roman characters (with the exceptions of Pluto and Uranus), most of the moon have names from Greek mythology. For example, Phobos and Deimos are the sons of Ares, the Greek version of Mars. Jupiter?s moons are all named for lovers and other close associates of Zeus (Jupiter). Saturn?s moons are named for Titans, the race that included Cronos (Saturn), Zeus? father. Neptune?s moons are named for mythological characters associated with water, and Charon was the ferryman of the dead who brought people to Pluto?s realm. By tradition, the discoverer of a moon gets to name it (now subject to approval by the International Astronomical Union). The son of the discoverer of the first two moons of Uranus (Sir William Herschel) decided to name Uranus? moons not for mythological characters, but instead for the king and queen of fairies in Shakespear?s A Midsummer Night?s Dream . This began a tradition whereby all uranian satellites are named for fairy characters in English drama. To read more about the names of the planets and their satellites, go to the U.S. Geological Survey?s nomenclature guide at http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/append7.html . *Earth* Moon *Mars * Phobos, Deimos *Jupiter* Metis, Adrastea, Amalthea, Thebe, Io, Europa, Ganymede, Callisto, Leda, Himalia, Lysithea, Elara, Ananke, Carme, Pasiphae, Sinope *Saturn * Pan, Atlas, Prometheus, Pandora, Epimetheus, Janus, Mimas, Enceladus, Tethys, Calypso, Telesto, Dione, Helene, Rhea, Titan, Hyperion, Iapetus, Phoebe *Uranus * Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Belinda, Puck, Miranda,, Ariel, Umbriel, Titania, Oberon *Neptune* Naiad, Thalassa, Despina, Galatea, Larissa, Proteus, Triton, Nereid *Pluto * Charon *Image Credit*: Image processing by Tim Parker (Jet Propulsion Laboratory) and Paul Schenk and Robert Herrick (Lunar and Planetary Institute), based on NASA images.
The New Solar System
PIA02973
Title The New Solar System
Original Caption Released with Image This solar-system montage of the nine planets and 4 large moons of Jupiter in our solar system are set against a false-color view of the Rosette Nebula. The light emitted from the Rosette Nebula results from the presence of hydrogen (red), oxygen (green) and sulfur (blue). Most of the planetary images in this montage were obtained by NASA's planetary missions, which have dramatically changed our understanding of the solar system in the past 30 years. The following lists the mission and link for additional information on each object and image.Mercury/Mariner 10 [ http://photojournal.jpl.nasa.gov/catalog/PIA02418 ]Venus/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA00072 ]Earth/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA00728 ]Moon/Lunar Orbiter [ http://photojournal.jpl.nasa.gov/catalog/PIA00094 ]Mars/Viking Orbiter 1 & 2 [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/wall/mars/hemisph.html ]Jupiter/Voyager 1 [ http://photojournal.jpl.nasa.gov/catalog/PIA01509 ]Io/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA02309 ]Europa/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA00502 ]Ganymede/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA01666 ]Callisto/Galileo [ http://photojournal.jpl.nasa.gov/catalog/PIA01298 ]Saturn/Voyager 1 [ http://photojournal.jpl.nasa.gov/catalog/PIA01383 ]Uranus/Voyager 2 [ http://photojournal.jpl.nasa.gov/catalog/PIA00032 ]Neptune/Voyager 2 [ http://photojournal.jpl.nasa.gov/catalog/PIA02210 ]Pluto/Hubble Space Telescope [ http://photojournal.jpl.nasa.gov/catalog/PIA00827 ]Rosette Nebula/Kitt Peak [ http://www.noao.edu/image_gallery/html/im0557.html ]
First ESA Faint Object Camer …
Title First ESA Faint Object Camera Science Images Pluto - the "Double Planet
August 2006: View of the Pla …
Description August 2006: View of the Planets
Full Description Just before the eastern sky brightens with sunrise, three planets and the waning crescent moon join the starry twilight tapestry. Then, as the bright stars of Gemini and Orion fade with oncoming dawn, the planets rise and shine. About 45 minutes before sunrise on Aug. 20 to 22 the planets Venus, Mercury and Saturn dance on the ecliptic -- the plane of Earth's orbit and the imaginary line tracing it in the sky. The sun, moon and planets appear to move along this line. Venus, rising an hour and a half before sunrise, is the easiest to see in the morning sky. Two hundred forty-one million kilometers (150 million miles) distant, Venus is Earth-sized. Mercury, at a distance of 183 million kilometers (114 million miles), is the fastest and smallest of the inner planets and appears brighter than the more distant Saturn. Saturn, 1,517 million kilometers (943 million miles) distant, was at conjunction with the sun just two weeks ago and now rises nearly an hour before sunrise. On Aug. 26 and 27, Saturn pairs with much brighter Venus at dawn. What other planets can we see in late August? Mars sets 45 minutes after sunset by month's end but is lost from view in the twilight, while brilliant Jupiter remains prominent as the only planet visible for a few hours during the late August evenings. Credit: NASA/JPL
Date August 18, 2006
Neptune: Big Blue Giant
Title Neptune: Big Blue Giant
Explanation This picture was taken by the Voyager 2 [ http://nssdc.gsfc.nasa.gov/planetary/voyager.html ] spacecraft in 1986 - the only spacecraft ever to visit Neptune. Neptune [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/neptune.html ] will be the farthest planet from the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap950813.html ] until 1999, when the elliptical orbit of Pluto will cause it to once again resume this status. Neptune [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/neptune.html ], like Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ], is composed mostly of liquid water, methane and ammonia, is surrounded by a thick gas atmosphere of mostly hydrogen and helium, and has many moons and rings. Neptune [ http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-neptune.html ]'s moon Triton [ http://antwrp.gsfc.nasa.gov/apod/ap950805.html ] is unlike any other and has active volcanoes. The nature of Triton [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/triton.html ]'s unusual orbit around Neptune is the focus of much discussion and speculation. Tomorrow's picture: Pluto: The Frozen Planet
Planets In The Sun
Title Planets In The Sun
Explanation Today [ http://science.nasa.gov/headlines/y2000/ast02may_1.htm ], all five naked-eye planets [ http://www.seds.org/nineplanets/nineplanets/ ] (Mercury, Venus, Mars, Jupiter, Saturn) plus the Moon and the Sun [ http://helios.gsfc.nasa.gov/ sun.html ] will at least approximately line-up. As viewed [ http://drumright.ossm.edu/astronomy/conjunctions.html ] from planet Earth, they will be clustered within about 26 degrees, the closest alignment for all these celestial bodies [ http://science.nasa.gov/headlines/y2000/ ast30mar_1m.htm#alignments ] since February 1962, when there was a solar eclipse [ http://antwrp.gsfc.nasa.gov/apod/ap990818.html ]! Such planetary alignments [ http://www.griffithobs.org/SkyAlignments.html ] are not dangerous, except of course that the Sun might hurt your eyes when you look at it [ http://antwrp.gsfc.nasa.gov/apod/ap981212.html ]. So it might be easier [ http://sohowww.nascom.nasa.gov/hotshots/ ] to appreciate today's solar system [ http://space.jpl.nasa.gov/ ] spectacle if
Charon Discovery Image
title Charon Discovery Image
date 06.22.1978
description On 22 June 1978, an astronomer at the U.S. Naval Observatory in Washington, D.C. was making routine measurements of photographic plates taken with the 1.55-meter (61-inch) Kaj Strand Astrometric Reflector at the USNO Flagstaff Station in Arizona. The purpose of these images was to refine the orbit of the far-flung planet Pluto to help compute a better ephemeris for this distant object. Astronomer James W. Christy had noticed that a number of the images of Pluto appeared elongated, but images of background stars on the same plate did not. Other plates showed the planet as a tiny, round dot. Christy examined a number of Pluto images from the USNO archives, and he noticed the elongations again. Furthermore, the elongations appeared to change position with respect to the stars over time. After eliminating the possibility that the elongations were produced by plate defects and background stars, the only plausible explanation was that they were caused by a previously unknown moon orbiting Pluto at a distance of about 19,600 kilometers (12,100 miles) with a period of just over six days. On 7 July 1978, the discovery was formally announced to the astronomical community and the world by the IAU Central Bureau for Astronomical Telegrams via IAU Circular 3241. The discovery received the provisional designation "1978 P 1", Christy proposed the name "Charon", after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto's underworld. Over the course of the next several years, another USNO astronomer, the late Robert S. Harrington, calculated that Pluto and its newly-found moon would undergo a series of mutual eclipses and occultations, beginning in early 1985. On 17 February 1985 the first successful observation of one of these transits was made at with the 0.9-meter (36-inch) reflector at the University of Texas McDonald Observatory, within 40 minutes of Harrington's predicted time. The IAU Circular announcing these confirming observations was issued on 22 February 1985. With this confirmation, the new moon was officially named Charon. Pluto was discovered at Lowell Observatory in 1930 by the late Clyde W. Tombaugh, an amateur astronomer from Kansas who was hired by the Observatory specifically to photograph the sky with a special camera and search for the planet predicted by the Observatory's founder, Percival Lowell. Lowell had deduced the existence of a "Planet X" by studying small anomalies in the orbits of Uranus and Neptune. As it turned out, Pluto's discovery was almost entirely serendipitous, Pluto's tiny mass was far too small to account for the anomalies, which were resolved when Voyager 2 determined more precise masses for Uranus and Neptune. The discovery of Charon has led to a much better understanding of just how tiny Pluto is. Its diameter is about 2274 km (1413 miles), and its mass is 0.25% of the mass of the Earth. Charon has a diameter of about 1172 kilometers (728, miles) and a mass of about 22% that of Pluto. The two worlds circle their common center of mass with a period of 6.387 days and are locked in a "super-synchronous" rotation: observers on Pluto's surface would always see Charon in the same part of the sky relative to their local horizon. Normally Pluto is considered the most distant world in the solar system, but during the period from January 1979 until February 1999 it was actually closer to the Sun than Neptune. It has the most eccentric and inclinced orbit of any of the major planets. This orbit won't bring Pluto back to its discovery position until the year 2178! *Image Credit*: U.S. Naval Observatory
Sky and Planets
Title Sky and Planets
Explanation On February 10th, an evocative [ http://www.jps.net/ssumner/ ] evening sky above Rocklin, California, USA inspired astrophotographer Steve Sumner to record this remarkable sight - five planets and the Moon. Near its first quarter phase, the bright Moon [ http://lunar.arc.nasa.gov/ ] was intentionally overexposed but Saturn [ http://www.jpl.nasa.gov/cassini/ ], Jupiter [ http://galileo.jpl.nasa.gov/ ], Mars [ http://mars.jpl.nasa.gov/ ], and Mercury [ http://sd-www.jhuapl.edu/MESSENGER/ ] (and, of course, planet Earth's [ http://www.earth.nasa.gov/ ] horizon) are all clearly visible in the deepening twilight. Notably absent in this grouping of naked-eye planets is Venus [ http://antwrp.gsfc.nasa.gov/apod/ap990903.html ] which is still putting in an early appearance as the morning star [ http://ispec.scibernet.com/station/morn_star.html ]. This month, Mercury has joined Venus in the dawn twilight while Saturn, Jupiter, and Mars still shine brightly in the western sky at nightfall [ http://www.skypub.com/sights/sights.shtml ] making another gorgeous close grouping with the crescent Moon [ http://www.inconstantmoon.com/ ].
Solar System Montage of Voya …
Title Solar System Montage of Voyager Images
Full Description This montage of images taken by the Voyager spacecraft of the planets and four of Jupiter's moons is set against a false-color Rosette Nebula with Earth's moon in the foreground. Studying and mapping Jupiter, Saturn, Uranus, Neptune, and many of their moons, Voyager provided scientists with better images and data than they had ever had before or expected from the program. Although launched sixteen days after Voyager 2, Voyager 1's trajectory was a faster path, arriving at Jupiter in March 1979. Voyager 2 arrived about four months later in July 1979. Both spacecraft were then directed to Saturn with Voyager 1 arriving in November 1980 and Voyager 2 in August 1981. Voyager 2 was then diverted to the remaining gas giants, Uranus in January 1986 and Neptune in August 1989. Data collection continues by both Voyager 1 and 2 as the renamed Voyager Interstellar Mission searches for the edge of the solar wind influence (the heliopause) and exits the Solar System. A shortened list of the discoveries of Voyager 1 and 2 include:the discovery of the Uranian and Neptunian magnetospheres (magnetic environments caused by various types of planet cores), the discovery of twenty-two new satellites including three at Jupiter, three at Saturn, ten at Uranus, and six at Neptune, Io was found to have active volcanism (the only other Solar System body than Earth to be confirmed), Triton was found to have active geyser-like structures and an atmosphere, Auroral Zones (where gases become excited after being hit by solar particles) were discovered at Jupiter, Saturn, and Neptune, Jupiter was found to have rings, Neptune, originally thought to be too cold to support such atmospheric disturbances, had large-scale storms.
Date UNKNOWN
NASA Center Jet Propulsion Laboratory
Venus: Earth's Sister Planet
Title Venus: Earth's Sister Planet
Explanation This picture in visible light was taken by the Galileo [ http://nssdc.gsfc.nasa.gov/planetary/galileo.html ] spacecraft. Venus [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/venus.html ] is very similar to Earth [ http://antwrp.gsfc.nasa.gov/apod/ap950622.html ] in size and mass - and so is sometimes referred to as Earth's sister planet - but Venus has a quite different climate. Venus' [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/venus.html ] thick clouds and closeness to the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap950813.html ] (only Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap950814.html ] is closer) make it the hottest planet - much hotter than the Earth. Humans could not survive there, and no life of any sort has ever been found. When Venus [ http://nssdc.gsfc.nasa.gov/photo_gallery/PhotoGallery-Venus.html ] is visible it is usually the brightest object in the sky after the Sun and the Moon. More than 20 spacecraft have visited Venus including Venera 9, which landed on the surface, and Magellan [ http://stardust.jpl.nasa.gov/mveg/guide.html ], which used radar to peer through the clouds and make a map of the surface. There are still many things about Venus's unusual atmosphere that astronomers don't understand. Tomorrow's picture: Uranus: The Tilted Planet
New Horizons at Jupiter
Title New Horizons at Jupiter
Explanation Headed for the first close-up exploration of the Pluto-Charon system [ http://www.plutoportal.net/ ] and the icy denizens of the Kuiper belt [ http://www.ifa.hawaii.edu/faculty/jewitt/kb.html ], NASA's New Horizons [ http://pluto.jhuapl.edu/mission.htm ] spacecraft is pictured here in an artist's vision of the robot probe outward bound. The dramatic scene [ http://www.swri.org/press/jest.htm ] depicts the 465 kilogram spacecraft about one year after a planned 2006 launch, following a flyby of gas giant Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap031114.html ]. While the Jupiter flyby [ http://www.swri.edu/9what/releases/ JEST.htm ] will be used as a gravity assist [ http://www.jpl.nasa.gov/basics/grav/primer.html ] maneuver to save fuel and cut travel time to the outer reaches of the Solar System [ http://www.seds.org/nineplanets/nineplanets/ nineplanets.html ], it will also provide an opportunity to test instruments and study the giant planet, its moons, and magnetic fields. The Sun is seen from eight hundred million kilometers away, with inner planets Earth, Venus, and Mercury aligned [ http://antwrp.gsfc.nasa.gov/apod/ap001014.html ] on the left. A dim crescent of outermost Galilean moon Callisto [ http://antwrp.gsfc.nasa.gov/apod/ap010731.html ], orbiting Jupiter just inside of the spacecraft's trajectory, appears to the upper right of the fading Sun. Left of Jupiter itself is Europa [ http://antwrp.gsfc.nasa.gov/apod/ap030919.html ] and in the distant background are the faint, unresolved stars and dust clouds of the Milky Way [ http://home.arcor-online.de/axel.mellinger/ ]. New Horizons' planned arrival at Pluto-Charon [ http://pluto.jhuapl.edu/plutocharon.htm ] is in the summer of 2015.
Nashville Four Planet Skylin …
Title Nashville Four Planet Skyline
Explanation So far this February, evening skies [ http://antwrp.gsfc.nasa.gov/apod/ap000504.html ] have been blessed with a glorious Moon and three bright planets, Venus [ http://www.library.utoronto.ca/utel/rp/poems/ longfe10.html ], Jupiter, and Saturn. But just last week, on January 30th, an extreme wide-angle lens allowed astrophotographer Larry Koehn to capture this twilight view of Moon and four planets above [ http://www.seds.org/nineplanets/nineplanets/ see.html ] Nashville, Tennessee, USA. These major solar system [ http://space.jpl.nasa.gov/ ] bodies lie along the ecliptic plane [ http://antwrp.gsfc.nasa.gov/apod/ap001014.html ] and so follow a diagonal line through the picture. Starting near the upper left corner is bright Jupiter [ http://starchild.gsfc.nasa.gov/docs/StarChild/ solar_system_level2/jupiter.html ], which takes on a slightly triangular shape due to the lens distortion. Just below and right of Jupiter is Saturn [ http://www.jpl.nasa.gov/cassini/english/kids/ saturn_in_sky.html ]. Continuing along the diagonal toward the lower right is an overexposed, six day old Moon [ http://www.inconstantmoon.com/ ] and brilliant Venus seemingly embedded in clouds. The fourth planet pictured is Mercury. Notoriously hard to see from planet Earth because it never wanders far from the Sun, Mercury is [ http://antwrp.gsfc.nasa.gov/apod/ap991111.html ] visible just above the lower right corner. The line from Jupiter to Mercury spans about 92 degrees across the Nashville sky.
Planets in the West
Title Planets in the West
Explanation Have you seen any bright planets lately? Chances are if you've been outside under clear skies [ http://currentsky.com/ ] just after sunset, then you have. Now shining in the west as bright "stars [ http://nfo.edu/astro/planets.htm ]" in the night sky, are all five planets of the solar system known to [ http://www.nasm.si.edu/ceps/etp/discovery/ etpdiscovery.html ] ancient astronomers - Mercury, Venus, Mars [ http://mars.jpl.nasa.gov/ funzone.html ], Saturn, and Jupiter [ http://www.seds.org/nineplanets/nineplanets/ jupiter.html ]. Recorded from Holt, Michigan, USA about 40 minutes after sunset on April 14th, this digital image [ http://www.pa.msu.edu/people/frenchj/const/index2.html ] captures three of them, Venus, Mars, and Saturn [ http://www.jpl.nasa.gov/solar_system/planets/ saturn_index.html ], along with a young crescent Moon [ http://antwrp.gsfc.nasa.gov/apod/ap000728.html ]. Also indicated are the Pleiades [ http://antwrp.gsfc.nasa.gov/apod/ap010506.html ] star cluster and bright red giant star Aldebaran [ http://www.earthsky.com/Features/ Skywatching/pronounce.html ] in Taurus. Mercury [ http://www.psrd.hawaii.edu/Jan97/ MercuryUnveiled.html ], setting, is lost in the trees and glow along the horizon, while Jupiter is off the top of this view. The coming weeks [ http://www.darkhorizons.org/planets.htm ] will see photo opportunities galore as all five planets gradually move closer together, posing after sunset with the Moon and stars in the western sky [ http://www.skyviewcafe.com/skyview.shtml ]. Venus [ http://antwrp.gsfc.nasa.gov/apod/ap020330.html ], Mars, and Saturn will form the closest trio, drawing within a 5 degree circle (about the apparent size of your fist with arm extended) above Aldebaran by May 3rd.
Planets Over Stonehenge
Title Planets Over Stonehenge
Explanation Stonehenge [ http://antwrp.gsfc.nasa.gov/apod/ap990912.html ], four thousand year old [ http://antwrp.gsfc.nasa.gov/apod/ap980408.html ] monument to the Sun [ http://www.hao.ucar.edu/public/education/archeoslides/ index.html ], provides an appropriate setting for this delightful snapshot [ http://www.astrocruise.com/planets.htm ] of the Sun's children [ http://www.seds.org/nineplanets/nineplanets/ ] gathering in planet Earth's sky. While the massive stone [ http://www.amherst.edu/~ermace/sth/poetry.html ] structure dates from around 2000 B.C. [ http://mathforum.org/dr.math/problems/masell10.1.97.html ], this arrangement of the visible planets [ http://skyandtelescope.com/observing/objects/planets/ article_572_1.asp ] was recorded only a few days ago on the evening of May 4th, 2002 A.D. Bright Jupiter stands highest above the horizon at the upper left. A remarkable, almost equilateral triangle [ http://mathforum.org/dr.math/faq/formulas/ faq.triangle.html ] formed by Saturn (left), Mars (top), and Venus (right) is placed just above the stones near picture center. Fighting the glow of the setting sun, Mercury can be spotted closest to the horizon, below and right of the planetary triad. Still easy to enjoy [ http://science.nasa.gov/headlines/y2002/24apr_relax.htm ] for casual sky gazers, this photogenic and slowly shifting planetary grouping [ http://science.nasa.gov/spaceweather/planets/ gallery_may02.html ] will be joined by a young crescent [ http://antwrp.gsfc.nasa.gov/apod/ap020419.html ] Moon beginning Monday, May 13.
Dusk of the Planets
Title Dusk of the Planets
Explanation A great grouping of planets [ http://www.nineplanets.org/ ] is now visible [ http://CarnegieScienceCenter.org/exhibits/planet_calendar.asp ] to the west just after sunset. Over the next two weeks, Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap010819.html ], Venus [ http://antwrp.gsfc.nasa.gov/apod/ap010916.html ], Earth, Mars [ http://antwrp.gsfc.nasa.gov/apod/ap010628.html ], Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap020205.html ], and Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap020215.html ] -- the innermost six planets of our Solar System [ http://www.nineplanets.org/overview.html ] -- can be seen in a single knowing glance. The image on the left [ http://www.astropix.com/HTML/H_OTHER/PLANETS.HTM ] captured them all in one frame. Connecting the planetary dots delineates the edge-on ecliptic [ http://antwrp.gsfc.nasa.gov/apod/ap990529.html ], the plane in which the planets orbit the Sun [ http://csep10.phys.utk.edu/astr161/lect/retrograde/copernican.html ]. The shot was taken on April 23 near Chatsworth, New Jersey [ http://www.state.nj.us/ ], USA [ http://www.cia.gov/cia/publications/factbook/geos/us.html ], and even includes scattered light from the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap000403.html ] and the Moon [ http://antwrp.gsfc.nasa.gov/apod/ap010218.html ]. Besides the planets, the Pleiades [ http://antwrp.gsfc.nasa.gov/apod/ap010506.html ] and Hyades [ http://www.astro.uiuc.edu/~kaler/sow/hyades-p.html ] open clusters [ http://www.seds.org/messier/open.html ] of stars are visible [ http://www.planetary.org/html/news/articlearchive/headlines/2002/alignment.htm ].
Moon and Planets by the Eiff …
Title Moon and Planets by the Eiffel Tower
Explanation The great evening grouping of planets [ http://antwrp.gsfc.nasa.gov/apod/ap020429.html ] is coming to an end. Before all the planets [ http://antwrp.gsfc.nasa.gov/apod/ap020510.html ] went their own separate directions [ http://CarnegieScienceCenter.org/exhibits/planet_calendar.asp ], however, the Moon [ http://antwrp.gsfc.nasa.gov/apod/ap010218.html ] was kind enough to pose [ http://science.nasa.gov/spaceweather/planets/gallery_may02.html ] with some of them. The planets [ http://www.nineplanets.org ] in the above picture [ http://perso.club-internet.fr/legault/planets.html ], taken last week, are Venus [ http://antwrp.gsfc.nasa.gov/apod/ap970507.html ] and Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap020205.html ]. Mars [ http://www.nineplanets.org/mars.html ], Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap010702.html ], and even Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap000320.html ] appear to the lower right of Venus [ http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-venus.html ] but are too dim to be seen. Over the next two weeks, the Moon will rise [ http://aa.usno.navy.mil/data/docs/RS_OneYear.html ] later and later passing a full phase [ http://antwrp.gsfc.nasa.gov/apod/ap990419.html ] on May 26. Venus and Jupiter will continue to shine, moving together [ http://SkyandTelescope.com/observing/objects/planets/article_572_4.asp ] until their closest approach on June 3. The Eiffel Tower [ http://www.tour-eiffel.fr/teiffel/uk/ ], however, is expected to remain right where it is.
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.
Jupiter's Rings
Title Jupiter's Rings
Explanation Astronomers using NASA's Voyager [ http://nssdc.gsfc.nasa.gov/planetary/voyager.html ] spacecraft to search for a ring system around Jupiter discovered these faint rings in 1979. Unlike Saturn's bright rings which are composed of chunks of rock and ice, Jupiter's rings [ http://ringside.arc.nasa.gov/www/jupiter/jupiter.html ] appear to consist of fine particles of dust. One possibility is that the dust is produced by impacts with Jupiter's inner moons. This false color image has been computer enhanced. The gas giant planets, Jupiter, Saturn, Uranus, and Neptune are all known to have rings. For more information about planetary ring systems see the Planetary Rings Node [ http://ringside.arc.nasa.gov/ ]. Tomorrow's picture: A Volcanic Moon
Description Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn.
Full Description The solar system's largest moon, Ganymede, is captured here alongside the planet Jupiter in a color picture taken by NASA's Cassini spacecraft on Dec. 3, 2000. Ganymede is larger than the planets Mercury and Pluto and Saturn's largest moon, Titan. Both Ganymede and Titan have greater surface area than the entire Eurasian continent on our planet. Cassini was 26.5 million kilometers (16.5 million miles) from Ganymede when this image was taken. The smallest visible features are about 160 kilometers (about 100 miles) across. The bright area near the south (bottom) of Ganymede is Osiris, a large, relatively new crater surrounded by bright icy material ejected by the impact which created it. Elsewhere, Ganymede displays dark terrains that NASA's Voyager and Galileo spacecraft have shown to be old and heavily cratered. The brighter terrains are younger and laced by grooves. Various kinds of grooved terrains have been seen on many icy moons in the solar system. These are believed to be the surface expressions of warm, pristine, water-rich materials that moved to the surface and froze. Ganymede has proven to be a fascinating world, the only moon known to have a magnetosphere, or magnetic environment, produced by a convecting metal core. The interaction of Ganymede's and Jupiter's magnetospheres may produce dazzling variations in the auroral glows in Ganymede's tenuous atmosphere of oxygen. 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. Credit: NASA/JPL/University of Arizona For higher resolution, click here.
Terrestrial Planet Interiors
title Terrestrial Planet Interiors
description *Mercury* Mercury has an average density of 5430 kilograms per cubic meter, which is second only to Earth among all the planets. It is estimated that the planet Mercury, like Earth, has a ferrous core with a size equivalent to two-thirds to three-fourths that of the planet's overall radius. The core is believed to be composed of an iron-nickel alloy covered by a mantle and surface crust. *Venus* It is believed that the composition of the planet Venus is similar to that of Earth. The planet crust extends to around 10-30 kilometers below the surface, under which the mantle reaches to a depth of some 3000 kilometers. The planet core comprises a liquid iron-nickel alloy. Average planet density is 5240 kilograms per cubic meter. *Earth* The Earth comprises three separate layers: a crust, a mantle, and a core (in descending order from the surface). The crust thickness averages 30 kilometers for land masses and 5 kilometers for seabeds. The mantle extends from just below the crust to some 2900 kilometers deep. The core below the mantle begins at a depth of around 5100 kilometers, and comprises an outer core (liquid iron-nickel alloy) and inner core (solid iron-nickel alloy). The crust is composed mainly of granite in the case of land masses and basalt in the case of seabeds. The mantle is composed primarily of peridotite and high-pressure minerals. Average planet density is 5520 kilograms per cubic meter. *Mars* Mars is roughly one-half the diameter of Earth. Due to its small size, it is believed that the martian center has cooled. Geological structure is mainly rock and metal. The mantle below the crust comprises iron-oxide-rich silicate. The core is made up of an iron-nickel alloy and iron sulfide. Average planet density is 3930 kilograms per cubic meter. *Pluto* The structure of Pluto is not very well understood at present. Nevertheless, spectroscopic observation from Earth in the 1970s has revealed that the planet surface is covered with methane ice. Surface temperature is -230?C (-382?F), and the frozen methane exhibits a bright coloration. However, with the exception of the polar caps, the frozen methane surface is seen to change to a dark red when eclipsed by its moon Charon. Average planet density is 2060 kilograms per cubic meter. The low average density requires that the planet must be a mix of ice and rock. *Image Credit*: Lunar and Planetary Institute
Moon and Planets Sky Credit …
Title Moon and Planets Sky Credit & Copyright: Wojtek Rychlik [ http://www.pikespeakphoto.com ]
Explanation Look up into the sky tonight [ http://science.nasa.gov/headlines/y2004/ 19mar_planets.htm ] and without a telescope or binoculars you might have a view [ http://astronomy.swin.edu.au/staff/gmackie/billions.html ] like this one of Moon, planets and stars. The lovely photo [ http://www.pikespeakphoto.com/planets.html ] was taken on March 23rd, and captures the crescent Moon on the horizon with Venus above it. Both brilliant celestial bodies are over-exposed. Farther above Venus is the tinted glow of Mars with the Pleiades star cluster just to the red planet's right. The V-shaped arrangement of stars [ http://antwrp.gsfc.nasa.gov/apod/ap040304.html ] to the left of Mars is the Hydaes star cluster. Bright red giant Aldebaran [ http://www.astro.uiuc.edu/~kaler/sow/ aldebaran.html ], not itself a member of the Hyades cluster, marks the top left of the V. During the next week [ http://www.griffithobs.org/planetsgather.html ], all five naked-eye planets, Mercury, Venus, Mars, Jupiter, and Saturn, along with the Moon will grace the evening sky [ http://skyandtelescope.com/observing/objects/planets/ article_1226_1.asp ] together - a lunar and planetary spectacle that can be enjoyed by skygazers [ http://www.spaceweather.com/ ] around the world. But look just after sunset, low on the western horizon, to see Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap030412.html ] before it sets. The next similar gathering [ http://antwrp.gsfc.nasa.gov/apod/ap000524.html ] of the planets will be in 2008.
An Atlas Centaur Rocket Laun …
Title An Atlas Centaur Rocket Launches
Explanation Atlas Centaur [ http://www.lerc.nasa.gov/Other_Groups/PAO/html/atlas2as.htm ] rockets have launched over 75 successful unmanned missions. These missions included the Surveyor [ http://antwrp.gsfc.nasa.gov/apod/ap951008.html ] series - the first vehicles to make soft landings on the Moon [ http://antwrp.gsfc.nasa.gov/apod/ap950903.html ], Pioneer [ http://pyroeis.arc.nasa.gov/pioneer/PNhome.html ] 10 and 11 - the first missions to fly by Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap951206.html ] and Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap950705.html ] and the first man-made objects able to leave our Solar System [ http://antwrp.gsfc.nasa.gov/apod/ap950819.html ], the Viking missions [ http://antwrp.gsfc.nasa.gov/apod/ap950721.html ] which landed on Mars [ http://antwrp.gsfc.nasa.gov/apod/ap950716.html ], several satellites in the High Energy Astrophysics Observatory [ http://heasarc.gsfc.nasa.gov/ ] (HEAO) series, Pioneer Venus [ http://nssdc.gsfc.nasa.gov/planetary/pioneer_venus.html ] which circled and mapped the surface of Venus [ http://antwrp.gsfc.nasa.gov/apod/ap950822.html ], and numerous Intelsat [ http://www.intelsat.int:8080/info/html/is5.html ] satellites. Of recent scientific interest was the Atlas [ http://www.ksc.nasa.gov/elv/ATLAS_CENTAUR/atlcent.htm ] launched SOHO [ http://sohowww.nascom.nasa.gov/index-text.html ] mission which will continually observe the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap950813.html ]. Atlas rockets are manufactured by Lockheed Martin [ http://www.mmc.com/ ] Co.
Titania's Trenches
Title Titania's Trenches
Explanation British astronomer Sir William Herschel [ http://star.arm.ac.uk/history/herschel.html ] discovered Titania and Oberon in January of 1787. He wasn't reading Shakespeare's [ http://the-tech.mit.edu/Shakespeare/works.html ]"A Midsummer Night's Dream" though, he was making the first telescopic observations of moons of the planet Uranus [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/uranus.html ] (a planet which he himself discovered in 1781 [ http://www-groups.dcs.st-and.ac.uk/~history/ HistTopics/Neptune_and_Pluto.html ]). In January of 1986, nearly 200 years later, NASA's robot explorer Voyager 2 became the only spacecraft to visit the remote Uranian [ http://antwrp.gsfc.nasa.gov/apod/ap990531.html ] system [ http://antwrp.gsfc.nasa.gov/apod/ap971103.html ]. Above is Voyager's highest resolution picture of Titania [ http://photojournal.jpl.nasa.gov/cgi-bin/ PIAGenCatalogPage.pl?PIA00039 ], Uranus' largest moon. The picture is a composite of two images recorded from a distance of 229,000 miles. The icy, rocky world [ http://antwrp.gsfc.nasa.gov/apod/ap960304.html ] is seen to be covered with impact craters. A prominent system of fault valleys, some nearly 1,000 miles long, is visible as trench-like features near the terminator (shadow line). Deposits of highly reflective material which may represent frost can be seen along the sun-facing valley walls. The large impact crater near the top, known as Gertrude [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/uranus/titacrat.html ], is about 180 miles across. At the bottom the 60 mile wide fault valley, Belmont Chasma [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/uranus/titachas.html ], cuts into crater Ursula. Titania itself [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/wall/titania.html ] is 1,000 miles in diameter.
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
Venus, Moon, and Neighbors
Title Venus, Moon, and Neighbors
Explanation Rising before the Sun on February 2nd, astrophotographer [ http://pages.prodigy.net/pam.orman/JoeGallery.html ] Joe Orman anticipated [ http://pages.prodigy.net/pam.orman/JoeAlmanac2000.html ] this apparition of the bright morning star [ http://ispec.scibernet.com/station/morn_star.html ] Venus near a lovely crescent Moon above a neighbor's house in suburban Phoenix, Arizona, USA. Fortunately, the alignment of bright planets and the Moon is one of the most inspiring sights in the night sky [ http://www.skypub.com/sights/skyevents/0004skyevents.html ] and one that is often easy to enjoy and share without any special equipment. Take tonight [ http://spacescience.com/headlines/y2000/ast30mar_1m.htm ], for example. Those blessed with clear skies can simply step outside near sunset and view a young crescent Moon very near three bright planets in the west Jupiter [ http://galileo.jpl.nasa.gov/ ], Mars [ http://mars.jpl.nasa.gov/mgs/ ], and Saturn [ http://www.jpl.nasa.gov/cassini/ ]. Jupiter will be the unmistakable brightest star near the Moon with a reddish Mars just to Jupiter's north and pale yellow Saturn directly above. Of course, these sky shows [ http://drumright.ossm.edu/astronomy/conjunctions.html ] create an evocative picture [ http://antwrp.gsfc.nasa.gov/apod/ap000310.html ] but the planets and Moon just appear to be near each other -- they are actually only approximately lined up and lie in widely separated orbits. Unfortunately, next month's highly publicized alignment of planets [ http://www.griffithobs.org/SkyAlignments.html ] on May 5th will be lost from view in the Sun's glare but such planetary alignments [ http://www.skypub.com/news/special/whypanic.html ] occur repeatedly and pose no danger [ http://www.badastronomy.com/bad/misc/planets.html ] to planet Earth.
Ganymede and Jupiter
PIA02862
Sol (our sun)
Imaging Science Subsystem
Title Ganymede and Jupiter
Original Caption Released with Image The solar system's largest moon, Ganymede, is captured here alongside the planet Jupiter in a color picture taken by NASA's Cassini spacecraft on Dec. 3, 2000. Ganymede is larger than the planets Mercury and Pluto and Saturn's largest moon, Titan. Both Ganymede and Titan have greater surface area than the entire Eurasian continent on our planet. Cassini was 26.5 million kilometers (16.5 million miles) from Ganymede when this image was taken. The smallest visible features are about 160 kilometers (about 100 miles) across. The bright area near the south (bottom) of Ganymede is Osiris, a large, relatively new crater surrounded by bright icy material ejected by the impact, which created it. Elsewhere, Ganymede displays dark terrains that NASA's Voyager and Galileo spacecraft have shown to be old and heavily cratered. The brighter terrains are younger and laced by grooves. Various kinds of grooved terrains have been seen on many icy moons in the solar system. These are believed to be the surface expressions of warm, pristine, water-rich materials that moved to the surface and froze. Ganymede has proven to be a fascinating world, the only moon known to have a magnetosphere, or magnetic environment, produced by a convecting metal core. The interaction of Ganymede's and Jupiter's magnetospheres may produce dazzling variations in the auroral glows in Ganymede's tenuous atmosphere of oxygen. 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.
Earth, Moon, and Jupiter, as …
PIA04529
Sol (our sun)
Mars Orbiter Camera
Title Earth, Moon, and Jupiter, as seen from Mars
Original Caption Released with Image MGS MOC Release No. MOC2-368, 22 May 2003 What does Earth look like when viewed from Mars? At 13:00 GMT on 8 May 2003, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) had an opportunity to find out. In addition, a fortuitous alignment of Earth and Jupiter--the first planetary conjunction viewed from another planet--permitted the MOC to acquire an image of both of these bodies and their larger satellites. At the time, Mars and the orbiting camera were 139 million kilometers (86 million miles) from Earth and almost 1 billion kilometers (nearly 600 million miles) from Jupiter. The orbit diagram, from 24-bit color to 8-bit color using a JPEG to GIF conversion program. These 8-bit color images were converted to 8-bit grayscale and an associated lookup table mapping each gray value of that image to a red-green-blue color triplet (RGB). Each color triplet was root-sum-squared (RSS), and sorted in increasing RSS value. These sorted lists were brightness-to-color maps for their respective images. Each brightness-to-color map was then used to convert the 8-bit grayscale MOC image to an 8-bit color image. This 8-bit color image was then converted to a 24-bit color image. The color image was edited to return the background to black. Three separate color tables were used: one each for the Earth, Moon and Jupiter. Jupiter's Galilean Satellites were not colored. To view images separately, see: Earth and Jupiter as viewed from Mars PIA04530 [ http://photojournal.jpl.nasa.gov/catalog/PIA04530 ], Earth and Moon as viewed from Mars PIA04531 [ http://photojournal.jpl.nasa.gov/catalog/PIA04531 ], Jupiter and its Galilean Satellites as viewed from Mars PIA04532 [ http://photojournal.jpl.nasa.gov/catalog/PIA04532 ]., shows the geometry at the time the images were obtained. Because Jupiter is over 5 times farther from the Sun than Earth, two different exposures were needed to image the two planets. The images are shown mosaiced together. The composite has been highly contrast-enhanced and "colorized" to show both planets and their satellites. The MGS MOC high resolution camera only takes grayscale (black-and-white) images, the color was derived from Mariner 10 and Cassini pictures of Earth/Moon and Jupiter, respectively, as described in the note below. Earth/Moon: This is the first image of Earth ever taken from another planet that actually shows our home as a planetary disk. Because Earth and the Moon are closer to the Sun than Mars, they exhibit phases, just as the Moon, Venus, and Mercury do when viewed from Earth. As seen from Mars by MGS on 8 May 2003 at 13:00 GMT (6:00 AM PDT), Earth and the Moon appeared in the evening sky. The MOC Earth/Moon image has been specially processed to allow both Earth (with an apparent magnitude of -2.5) and the much darker Moon (with an apparent magnitude of +0.9) to be visible together. The bright area at the top of the image of Earth is cloud cover over central and eastern North America. Below that, a darker area includes Central America and the Gulf of Mexico. The bright feature near the center-right of the crescent Earth consists of clouds over northern South America. The image also shows the Earth-facing hemisphere of the Moon, since the Moon was on the far side of Earth as viewed from Mars. The slightly lighter tone of the lower portion of the image of the Moon results from the large and conspicuous ray system associated with the crater Tycho. Jupiter/Galilean Satellites: When Galileo first turned his telescope toward Jupiter four centuries ago, he saw that the giant planet had four large satellites, or moons. These, the largest of dozens of moons that orbit Jupiter, later became known as the Galilean satellites. The larger two, Callisto and Ganymede, are roughly the size of the planet Mercury, the smallest, Io and Europa, are approximately the size of Earth's Moon. This MGS MOC image, obtained from Mars orbit on 8 May 2003, shows Jupiter and three of the four Galilean satellites: Callisto, Ganymede, and Europa. At the time, Io was behind Jupiter as seen from Mars, and Jupiter's giant red spot had rotated out of view. This image has been specially processed to show both Jupiter and its satellites, since Jupiter, at an apparent magnitude of -1.8, was much brighter than the three satellites. A note about the coloring process: The MGS MOC high resolution camera only takes grayscale (black-and-white) images. To "colorize" the image, a Mariner 10 Earth/Moon image taken in 1973 was used to color the MOC Earth and Moon picture, and a recent Cassini image acquired during its Jupiter flyby was used to color the MOC Jupiter picture. The procedure used was as follows: the Mariner 10 and Cassini color images were converted
Earth, Moon, and Jupiter, as …
PIA04529
Sol (our sun)
Mars Orbiter Camera
Title Earth, Moon, and Jupiter, as seen from Mars
Original Caption Released with Image MGS MOC Release No. MOC2-368, 22 May 2003 What does Earth look like when viewed from Mars? At 13:00 GMT on 8 May 2003, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) had an opportunity to find out. In addition, a fortuitous alignment of Earth and Jupiter--the first planetary conjunction viewed from another planet--permitted the MOC to acquire an image of both of these bodies and their larger satellites. At the time, Mars and the orbiting camera were 139 million kilometers (86 million miles) from Earth and almost 1 billion kilometers (nearly 600 million miles) from Jupiter. The orbit diagram, from 24-bit color to 8-bit color using a JPEG to GIF conversion program. These 8-bit color images were converted to 8-bit grayscale and an associated lookup table mapping each gray value of that image to a red-green-blue color triplet (RGB). Each color triplet was root-sum-squared (RSS), and sorted in increasing RSS value. These sorted lists were brightness-to-color maps for their respective images. Each brightness-to-color map was then used to convert the 8-bit grayscale MOC image to an 8-bit color image. This 8-bit color image was then converted to a 24-bit color image. The color image was edited to return the background to black. Three separate color tables were used: one each for the Earth, Moon and Jupiter. Jupiter's Galilean Satellites were not colored. To view images separately, see: Earth and Jupiter as viewed from Mars PIA04530 [ http://photojournal.jpl.nasa.gov/catalog/PIA04530 ], Earth and Moon as viewed from Mars PIA04531 [ http://photojournal.jpl.nasa.gov/catalog/PIA04531 ], Jupiter and its Galilean Satellites as viewed from Mars PIA04532 [ http://photojournal.jpl.nasa.gov/catalog/PIA04532 ]., shows the geometry at the time the images were obtained. Because Jupiter is over 5 times farther from the Sun than Earth, two different exposures were needed to image the two planets. The images are shown mosaiced together. The composite has been highly contrast-enhanced and "colorized" to show both planets and their satellites. The MGS MOC high resolution camera only takes grayscale (black-and-white) images, the color was derived from Mariner 10 and Cassini pictures of Earth/Moon and Jupiter, respectively, as described in the note below. Earth/Moon: This is the first image of Earth ever taken from another planet that actually shows our home as a planetary disk. Because Earth and the Moon are closer to the Sun than Mars, they exhibit phases, just as the Moon, Venus, and Mercury do when viewed from Earth. As seen from Mars by MGS on 8 May 2003 at 13:00 GMT (6:00 AM PDT), Earth and the Moon appeared in the evening sky. The MOC Earth/Moon image has been specially processed to allow both Earth (with an apparent magnitude of -2.5) and the much darker Moon (with an apparent magnitude of +0.9) to be visible together. The bright area at the top of the image of Earth is cloud cover over central and eastern North America. Below that, a darker area includes Central America and the Gulf of Mexico. The bright feature near the center-right of the crescent Earth consists of clouds over northern South America. The image also shows the Earth-facing hemisphere of the Moon, since the Moon was on the far side of Earth as viewed from Mars. The slightly lighter tone of the lower portion of the image of the Moon results from the large and conspicuous ray system associated with the crater Tycho. Jupiter/Galilean Satellites: When Galileo first turned his telescope toward Jupiter four centuries ago, he saw that the giant planet had four large satellites, or moons. These, the largest of dozens of moons that orbit Jupiter, later became known as the Galilean satellites. The larger two, Callisto and Ganymede, are roughly the size of the planet Mercury, the smallest, Io and Europa, are approximately the size of Earth's Moon. This MGS MOC image, obtained from Mars orbit on 8 May 2003, shows Jupiter and three of the four Galilean satellites: Callisto, Ganymede, and Europa. At the time, Io was behind Jupiter as seen from Mars, and Jupiter's giant red spot had rotated out of view. This image has been specially processed to show both Jupiter and its satellites, since Jupiter, at an apparent magnitude of -1.8, was much brighter than the three satellites. A note about the coloring process: The MGS MOC high resolution camera only takes grayscale (black-and-white) images. To "colorize" the image, a Mariner 10 Earth/Moon image taken in 1973 was used to color the MOC Earth and Moon picture, and a recent Cassini image acquired during its Jupiter flyby was used to color the MOC Jupiter picture. The procedure used was as follows: the Mariner 10 and Cassini color images were converted
Venus: Earth's Cloudy Twin C …
Title Venus: Earth's Cloudy Twin Credit: Galileo [ http://galileo.jpl.nasa.gov/ ] Spacecraft, JPL [ http://www.jpl.nasa.gov/ ], NASA [ http://www.nasa.gov/ ];
Explanation This picture by the Galileo spacecraft [ http://nssdc.gsfc.nasa.gov/planetary/galileo.html ] shows just how cloudy Venus [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/venus.html ] is. Venus [ http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=34067 ] is very similar to Earth [ http://antwrp.gsfc.nasa.gov/apod/ap010204.html ] in size and mass - and so is sometimes referred to as Earth's sister planet - but Venus [ http://pds.jpl.nasa.gov/planets/welcome/venus.htm ] has a quite different climate. Venus [ http://spacelink.nasa.gov/NASA.Projects/Space.Science/Solar.System/Pioneer.Venus/Venus.Discoveries ]' thick clouds and closeness to the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap980830.html ] (only Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap010819.html ] is closer) make it the hottest planet - much hotter than the Earth [ http://antwrp.gsfc.nasa.gov/apod/earth.html ]. Humans could not survive there, and no life of any sort has ever been found. When Venus is visible [ http://www.space.com/spacewatch/venus_guide_031024.html ] it is usually the brightest object in the sky after the Sun and the Moon [ http://antwrp.gsfc.nasa.gov/apod/moon.html ]. More than 20 spacecraft have visited Venus [ http://nssdc.gsfc.nasa.gov/photo_gallery/PhotoGallery-Venus.html ] including Venera 9 [ http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1975-050D ], which landed on the surface, and Magellan [ http://www.jpl.nasa.gov/magellan/ ], which used radar to peer through the clouds and make a map of the surface [ http://antwrp.gsfc.nasa.gov/apod/ap030427.html ]. This visible light picture of Venus [ http://antwrp.gsfc.nasa.gov/apod/venus.html ] was taken by the Galileo spacecraft [ http://antwrp.gsfc.nasa.gov/apod/ap951206.html ] that orbited Jupiter from 1995 to 2003. Many things about Venus remain unknown, including the cause of mysterious bursts of radio waves [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1995JATP...57..557S ].
Martian Moons Transit the Su …
The upper-left of these imag …
6/9/08
Description The upper-left of these images shows the passing, or transit, of the Martian moon Deimos across the sun. This event is similar to solar eclipses seen from Earth in which our moon crosses in front of the sun. The bottom three images show Phobos, Mars's other moon, transiting the sun. The potato-shaped Phobos is roughly 15 miles across, about twice the size of Deimos. Deimos appears so much smaller because it is also a bit more than twice as far away from Mars as Phobos is. The Mars Exploration Rover Opportunity took images of both moons on different days in March 2004. Image credit: NASA/JPL/Cornell
Date 6/9/08
A Double Conjunction Eclipse
Title A Double Conjunction Eclipse
Explanation The crescent Moon [ http://www.seds.org/nineplanets/nineplanets/luna.html ], Venus [ http://www.hawastsoc.org/solar/eng/venus.htm ], and Jupiter [ http://pds.jpl.nasa.gov/planets/welcome/jupiter.htm ] all appeared together in the early morning hours of April 23rd. Some locations on Earth [ http://ceps.nasm.edu:2020/RPIF/EARTH/earth.html ] were able to witness [ http://www.staigerland.com/live/astrocam/ ] a rare double conjunction [ http://www.oregano.demon.co.uk/terms.htm#conjunc ] eclipse, where the Moon [ http://antwrp.gsfc.nasa.gov/apod/ap980129.html ] occulted both Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap980202.html ] and Venus [ http://antwrp.gsfc.nasa.gov/apod/ap970603.html ] at the same time. The next [ http://www.skypub.com/news/news.shtml ] double conjunction eclipse [ http://antwrp.gsfc.nasa.gov/apod/ap970924.html ] will involve Mercury [ http://antwrp.gsfc.nasa.gov/apod/ap971130.html ] and Mars [ http://www.seds.org/nineplanets/nineplanets/mars.html ] and will occur on February 13, 2056.
A Western Sky at Twilight
Title A Western Sky at Twilight
Explanation On April 23rd, the Moon along with planets Saturn, Mars, and Venus (and planet Earth of course ...) were all visible [ http://science.nasa.gov/headlines/y2004/ 21apr_planets2.htm ] in the west at twilight, captured here [ http://www.nightskyevents.com/ ] from a site near Saylorvillle Lake north of Des Moines, Iowa, USA. Putting your cursor [ http://www.fourmilab.ch/yoursky/ ] over the image will label our fellow solar system wanderers [ http://liftoff.msfc.nasa.gov/academy/time/ weekdays.html ] and also reveal the approximate trajectory of the ecliptic plane [ http://antwrp.gsfc.nasa.gov/apod/ap001014.html ] - defined by Earth's orbit around the Sun - angling above the western horizon. After sunset tonight, the western sky will present a similar arrangement of planets, although the Moon will have moved east out of the picture, passing bright Jupiter along the ecliptic and heading for May 4th's total lunar eclipse [ http://www.xs4all.nl/~carlkop/eclipsmaan/leclips2004.html ]. May could also [ http://skyandtelescope.com/observing/objects/comets/ article_1238_1.asp ] be a good month for comets [ http://skyandtelescope.com/observing/objects/comets/ article_1229_2.asp ].
Three Planets by the Sea
Title Three Planets by the Sea
Explanation On Tuesday, June 28th, the setting Sun flooded the horizon with a beautiful warm light in this view from [ http://homepages.picknowl.com.au/sparda/ NEW/Newall.htm ] the beach beside the pier at Brighton in Adelaide, South Australia [ http://www.nla.gov.au/ ]. The Sun also illuminated three planets gathered in the western sky [ http://antwrp.gsfc.nasa.gov/apod/ap050624.html ], Mercury, Venus, and Saturn. From this perspective Mercury [ http://www.fourmilab.ch/images/3planets/ elongation.html ] is at the highest point in the celestial triangle, brilliant Venus [ http://www.fourmilab.ch/images/venus_daytime/ ] is just below, and Saturn stands farther to the left and below the close pair [ http://www.alpheratz.net/observing/ VenusMercuryAppulse_2005-06-27/ ]. Of course, the planets only appear close together on the sky but are actually quite far apart in space. The orbits [ http://www.fourmilab.ch/cgi-bin/uncgi/ Solar/action?sys=-Sf ] of Mercury and Venus are both interior to Earth's orbit, while gas giant Saturn [ http://nssdc.gsfc.nasa.gov/planetary/factsheet/ saturnfact.html ] lies in the outer solar system, over nine astronomical units [ http://neo.jpl.nasa.gov/glossary/au.html ] from the Sun. Late next week [ http://skyandtelescope.com/observing/ataglance/ article_110_1.asp ], Venus and Mercury will share western skies with the young crescent Moon [ http://antwrp.gsfc.nasa.gov/apod/ap050513.html ].
Astronaut Exercise
In the next 50 years, NASA p …
7/8/08
Description In the next 50 years, NASA plans to send astronauts to the Moon and Mars. These astronauts must follow a strenuous exercise program in-flight to prevent the health effects of space flight. These effects include decrease in bone and muscle mass, strength, sensory-motor function (i.e. balance), and the ability to perform aerobic exercise.
Date 7/8/08
Description Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn.
Full Description Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. Credit: NASA/JPL/University of Arizona (PIA02826) For higher resolution, click here., These two images, taken by NASA's Cassini spacecraft, show Jupiter in a near-infrared wavelength, and catch Europa, one of Jupiter's largest moons, at different phases. Cassini's narrow-angle camera took both images, the upper one from a distance of 69.9 million kilometers (43.4 million miles) on Oct. 17, 2000, and the lower one from a distance of 65.1 million kilometers (40.4 million miles) on Oct. 22, 2000. Both were taken at a wavelength of 727 nanometers, which is in the near-infrared region of the electromagnetic spectrum. The camera's 727-nanometer filter accepts only a narrow spectral range centered on a relatively strong absorption feature due to methane gas. In this spectral region, the amount of light reflected by Jupiter's clouds is only half that reflected in a nearby spectral region outside the methane band. The features that are brightest in these images are the highest and thickest clouds, such as the Great Red Spot and the band of clouds girding the equator, as these scatter sunlight back to space before it has a chance to be absorbed by the methane gas in the atmosphere. This stratigraphic effect can be seen even more prominently in an image released on Oct. 23, 2000, taken in the stronger methane band at 889 nanometers, in which the only bright features are the highest hazes over the equator, the poles and the Great Red Spot. By comparing images taken in the 727 nanometer filter with others taken at 889 nanometers and at a weaker methane band at 619 nanometers, researchers will probe the heights and thickness of clouds in Jupiter's atmosphere. Europa, a satellite of Jupiter about the size of Earth's Moon, is visible to the left of Jupiter in the upper image, and in front of the planet in the lower image. Another of Jupiter's Galilean satellites, Ganymede, which is larger than the planet Mercury, is to the right in the upper image, with brightness variations visible across its surface. In the upper image, Europa is caught entering Jupiter's shadow, and hence appears as a bright crescent, in the lower image, it is seen about one-and-a-half orbits later, in transit across the face of the planet. Because there is neither methane nor any strong absorber in this spectral region on the surface of Europa, it appears strikingly white and bright compared to Jupiter. Imaging observations of the moons Europa, Io and Ganymede entering and passing through Jupiter's shadow are planned for the two-week period surrounding Cassini's closest approach on Dec. 30, 2000. The purpose of these eclipse observations is to detect and measure the variability of emissions that arise from the interaction of the satellites' tenuous atmospheres with the charged particles trapped in Jupiter's magnetic field. At the times these images were taken, Cassini was about 3.3 degrees above Jupiter's equatorial plane, and the Sun-Jupiter-spacecraft angle was about 20 degrees. Cassini is a cooperative project of NASA, the European Space Agency and the Italian
Apollo 15 on the Launch Pad
Lightening flashes in the sk …
5/6/09
Description Lightening flashes in the sky behind the Saturn V rocket that will propel Apollo 15 to the moon, July 25, 1971. Image Credit: NASA
Date 5/6/09
Total Eclipse of the Sun
On December 3, 2002, people …
6/9/08
Description On December 3, 2002, people in Australia received a rare 32-second celestial show as the moon completely obscured the sun, creating a ring of light. Solar eclipses provide experts an opportunity to study the sun's outer atmosphere, called the corona. This total eclipse was the first to cover Australian shores since 1976. The next is not predicted to occur for several more decades. While people in Australia were observing the solar eclipse, the Solar and Heliospheric Observatory (SOHO) spacecraft also had its eye on the sun. From its unique vantage point in space, scientists have been able to monitor the explosions on the sun that can impact us here on Earth. This image combines a photograph of the solar eclipse (showing the halo-like corona) with data taken by the Extreme Ultraviolet Imaging Telescope instrument aboard SOHO (showing the green inner regions). Image credit: NASA/ESA Text credit: NASA's Earth Observatory
Date 6/9/08
STEREO Sees Lunar Transit
This transit of the moon acr …
6/9/08
Description This transit of the moon across the sun on Feb. 25, 2007, could not be seen from Earth. This sight was visible only from the STEREO-B spacecraft in its orbit about the sun, trailing behind the Earth. NASA's STEREO mission consists of two spacecraft launched in October 2006 to study solar storms. When STEREO-B captured this image, it was about one million miles from the Earth. That's about 4.4 times farther away from the moon than we are on Earth. As a result, the moon appeared about 4.4 times smaller than what we are used to. This alignment of STEREO-B and the moon was not just due to luck. It was arranged with a small tweak to STEREO-B's orbit in December 2006. The sun as it appears here is a composite of images in four different wavelengths of extreme ultraviolet light that were separated into color channels and then recombined. Image credit: NASA
Date 6/9/08
2008 Solar Eclipse Diamond R …
This "diamond ring" image sh …
8/6/08
Description This "diamond ring" image shows the Aug. 1, 2008, solar eclipse at a point when the moon almost completely covered up the body of the sun. Credit: The Exploratorium
Date 8/6/08
Arctic Eclipse
NASA's Terra satellite was r …
8/4/08
Description NASA's Terra satellite was rounding the top of the globe, making its way from the eastern tip of Siberia and across the Arctic Ocean towards northern Norway and northwest Russia, when it captured this unique view of a total solar eclipse on Aug. 1, 2008. The circular disk of the Moon casts an oval-shaped shadow across the left edge of this image. In the region of totality, where the Moon entirely obscures the Sun, the shadow is complete. The edges of the shadow are fuzzy, gradually lightening from black to red, brown, and yellow until the shadow is no longer discernable. In these areas of semi-shadow, the Sun is only partially blocked. On any other day, the photo-like view captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite would be brilliant white since both the ever-present Arctic clouds and the ice that caps the northern sea reflect light. In this image, however, it is as if the world is painted in sepia: the low light casts a yellow-brown glow on much of the scene. The image was captured between 9:35 and 9:45 UTC. In the area shown in the image, the Sun was completely obscured for about two minutes. As Earth rotated, the shadow moved southeast across the surface. At the same time, the satellite crossed the Arctic, its path nearly perpendicular to the eclipse. Because the shadow was moving across Earth's surface as the satellite approached, it has a long oblong shape in this image. In an instantaneous snapshot from a platform that was not moving relative to Earth, the shadow would be more circular. Image credit: Jeff Schmaltz, NASA's MODIS Rapid Response Team Text credit: Holli Riebeek, NASA's Earth Observatory
Date 8/4/08
Eclipse View from the ISS
The International Space Stat …
6/9/08
Description The International Space Station (ISS) was in position to view the umbral (ground) shadow cast by the moon as it moved between Earth and the sun during a solar eclipse on March 29, 2006. This astronaut image captures the umbral shadow across southern Turkey, northern Cyprus and the Mediterranean Sea. Credit: NASA
Date 6/9/08
2008 Solar Eclipse at Totali …
This image shows the Aug. 1, …
8/6/08
Description This image shows the Aug. 1, 2008, solar eclipse at the point of totality, when the moon completely blocks out the body of the sun, revealing the normally hidden, halo-like corona. Credit: The Exploratorium
Date 8/6/08
Ganymede Mosaic
Title Ganymede Mosaic
Explanation Ganymede [ http://www.seds.org/nineplanets/nineplanets/ganymede.html ], one of the four Galilean moons [ http://www.jpl.nasa.gov/galileo/ganymede/discovery.html ] of Jupiter, is the largest moon in the Solar System. With a diameter of 5,260 kilometers it is even larger [ http://www.seds.org/nineplanets/nineplanets/datamax.html ] than planets Mercury and Pluto and just over three quarters the size of Mars. Ganymede is [ http://www.jpl.nasa.gov/galileo/ganymede/fact.html ] locked in synchronous rotation [ http://www.seds.org/nineplanets/nineplanets/help.html#syncrot ] with Jupiter. This detailed mosaic [ http://photojournal.jpl.nasa.gov/cgi-bin/ PIAGenCatalogPage.pl?PIA01666 ] of images from the Galileo spacecraft shows the trailing hemisphere of this planet-sized moon. Speckled with bright young craters, Ganymede's surface shows a mixture of old, dark, cratered [ http://antwrp.gsfc.nasa.gov/apod/ap980722.html ] terrain and lighter regions laced with grooves and ridges [ http://antwrp.gsfc.nasa.gov/apod/ap960711.html ]. Ganymede's true colors tend toward subtle browns and grays, but this mosaic's colors have been enhanced to increase surface contrasts. The violet shades extending from the top and bottom are likely due to frost particles in Ganymede's polar regions.
Pluto: The Frozen Planet
Title Pluto: The Frozen Planet
Explanation This portrait of Pluto [ http://oposite.stsci.edu/pubinfo/pr/94/17.html ] and its companion Charon [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ pluto.html#charon ] was taken by the Hubble Space Telescope in 1994. Pluto is [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/pluto.html ] usually the most distant planet from the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap960916.html ] but because of its eccentric orbit Pluto crossed inside of Neptune's [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/neptune.html ] orbit in 1979. On Thursday, February 11th, it crossed back out, recovering its status [ http://www.lowell.edu/users/buie/pluto/ ] as the most distant of nine planets [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ ]. Pluto [ http://www.iau.org/PlutoPR.html ] is still considered to be a planet, although very little is known about it compared to other planets. Pluto [ http://antwrp.gsfc.nasa.gov/apod/ap980708.html ] is smaller than any other planet and even smaller than several other planet's moons. Pluto is [ http://dosxx.colorado.edu/plutohome.html ] probably composed of frozen rock and ice, much like Neptune's moon Triton [ http://antwrp.gsfc.nasa.gov/apod/ap971123.html ]. Pluto has not yet been visited by a spacecraft, but a mission is being planned [ http://www.jpl.nasa.gov/pluto/pkexprss.htm ] for the next decade.
Hubble Confirms New Moons of …
Title Hubble Confirms New Moons of Pluto
Pale Blue Orb (1)
Description Pale Blue Orb
Full Description Not since NASA's Voyager 1 spacecraft saw our home as a pale blue dot from beyond the orbit of Neptune has Earth been imaged in color from the outer solar system. Now, Cassini casts powerful eyes on our home planet, and captures Earth, a pale blue orb -- and a faint suggestion of our moon -- among the glories of the Saturn system. Earth is captured here in a natural color portrait made possible by the passing of Saturn directly in front of the sun from Cassini's point of view. At the distance of Saturn's orbit, Earth is too narrowly separated from the sun for the spacecraft to safely point its cameras and other instruments toward its birthplace without protection from the sun's glare. The Earth-and-moon system is visible as a bright blue point on the right side of the image above center. Here, Cassini is looking down on the Atlantic Ocean and the western coast of north Africa. The phase angle of Earth, seen from Cassini is about 30 degrees. A magnified view of the image taken through the clear filter (monochrome) shows the moon as a dim protrusion to the upper left of Earth. Seen from the outer solar system through Cassini's cameras, the entire expanse of direct human experience, so far, is nothing more than a few pixels across. Earth no longer holds the distinction of being our solar system's only "water world," as several other bodies suggest the possibility that they too harbor liquid water beneath their surfaces. The Saturnian moon, Enceladus, is among them, and is also captured on the left in this image (see inset), with its plume of water ice particles and swathed in the blue E ring which it creates. Delicate fingers of material extend from the active moon into the E ring. See Ghostly Fingers of Enceladus, for a more detailed view of these newly-revealed features. The narrow tenuous G ring and the main rings are seen at the right. The view looks down from about 15 degrees above the un-illuminated side of the rings. Images taken using red, green and blue spectral filters were combined to create this view. The image was taken by the Cassini spacecraft wide-angle camera on Sept. 15, 2006, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Saturn and at a sun-Saturn-spacecraft angle of almost 179 degrees. Image scale is 129 kilometers (80 miles) per pixel. At this time, Cassini was nearly 1.5 billion kilometers (930 million miles) from Earth. 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 mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov ., The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/Space Science Institute
Date September 19, 2006
Uranus' Largest Moon: Titani …
Title Uranus' Largest Moon: Titania
Explanation Titania's tortured terrain is a mix of valleys and craters. NASA's interplanetary robot spacecraft Voyager [ http://spacelink.msfc.nasa.gov/NASA.Projects/Planetary.Probes/Voyager/Mission.Summary ] 2 passed this moon of Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] in 1986 and took the above photograph. The photograph was then transmitted back to earth by radio [ http://www.science.uwaterloo.ca/physics/p13news/number_2/maxnew-2.html ]. The valleys of Titania [ http://bang.lanl.gov/solarsys/titania.htm ] resemble those on Ariel [ http://antwrp.gsfc.nasa.gov/apod/ap960303.html ] indicate that Titania underwent some unknown tumultuous resurfacing event in its distant past. Although Titania [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/titania.html ] is Uranus' largest moon, it is still much smaller than Triton [ http://antwrp.gsfc.nasa.gov/apod/ap950805.html ] - the largest moon of Uranus' sister planet Neptune [ http://antwrp.gsfc.nasa.gov/apod/ap950817.html ]. Titania is essentially a large dirty iceball that orbits Uranus - it is composed of about half water-ice and half rock. Titania was discovered by William Hershel [ http://www.dsi.unimi.it/Users/Students/amoroso/sun/fortunes/life-e.html ] in 1787.
1 2 3 489 90
1-50 of 4,472