The document provides an overview of the objects in our solar system, including the sun, eight planets, asteroids, comets, and meteoroids. It describes the key characteristics of each, such as the inner terrestrial planets being made of rock and metal versus the outer gas giants consisting mostly of hydrogen and helium. Images and facts are presented about traits like Venus' dense carbon dioxide atmosphere, Jupiter's Great Red Spot, and Neptune's blue color from methane gas.
HMCS Max Bernays Pre-Deployment Brief (May 2024).pptx
Solar System
1. Our Solar System Image: Lunar and Planetary Laboratory: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=178 FYI … Distance Not To Scale …
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8. Where Do Atmospheres Come From? Image from LPI: http://www.lpi.usra.edu/education/timeline/gallery/slide_33.html
9. All Planets with Volcanism – Including Earth! Volcanism - Volcanic action (gases and dust rising into the air from deep inside earth) Images from LPI: http://www.lpi.usra.edu/education/timeline/gallery/slide_17.html and http://www.lpi.usra.edu/education/timeline/gallery/slide_47.html
16. Giant Red Spot Storms on Jupiter Hubble images of Great Red Spot at http://hubblesite.org/newscenter/archive/releases/solar%20system/jupiter/1999/29/image/a/results/20/
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18. Can see it in the night sky without a telescope! Cassini image at: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=1383
19. Hubble image at http://hubblesite.org/newscenter/archive/releases/2006/47/image/b/ Uranus First planet discovered with a telescope!
26. Our Solar System Photo montage from: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=2167
Notes de l'éditeur
This image shows the Sun and 8 planets approximately to scale. The order of these bodies are: Sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
SOHO Image Extreme Ultraviolet Imaging Telescope (EIT) image of a huge, handle-shaped prominence taken on Sept. 14,1999 taken in the 304 angstrom wavelength - Prominences are huge clouds of relatively cool dense plasma suspended in the Sun's hot, thin corona. At times, they can erupt, escaping the Sun's atmosphere. Emission in this spectral line shows the upper chromosphere at a temperature of about 60,000 degrees K. Every feature in the image traces magnetic field structure. The hottest areas appear almost white, while the darker red areas indicate cooler temperatures. http://photojournal.jpl.nasa.gov/catalog/PIA03149 More information on Sun at http://solarviews.com/eng/sun.htm And at http://www.seds.org/nineplanets/nineplanets/sol.html And at http://sohowww.nascom.nasa.gov/
Ida This view of the asteroid 243 Ida was acquired by the Galileo spacecraft at ranges of 3,057 to 3,821 kilometers (1,900 to 2,375 miles) on August 28, 1993, about 3.5 minutes before the spacecraft made its close approach to the asteroid. This view shows numerous craters, including many degraded craters larger than any seen on Gaspra. The south pole is believed to be in the dark side near the middle of the asteroid. (Courtesy NASA/JPL) More information on asteroids at: http://nssdc.gsfc.nasa.gov/planetary/text/asteroids.txt And at http://www.nineplanets.org/asteroids.html
Information about Mercury at http://www.nineplanets.org/mercury.html And at http://solarviews.com/eng/mercury.htm
P-42383 MGN-114 May 26, 1993 This global view of the surface of Venus is centered at 90 degrees east longitude. Magellan synthetic aperture radar mosaics from the three eight-month cycles of Magellan radar mapping are mapped onto a computer-simulated globe to create this image. Magellan obtained coverage of 98 percent of the surface of Venus. Remaining gaps are filled with data from previous Venus missions -- the Venera 15 and 16 radar and Pioneer-Venus Orbiter altimetry -- and data from Earth-based radar observations from the Arecibo radio telescope. Simulated color is used to enhance small-scale structures. The simulated hues are based on color images obtained by the Venera 13 and 14 landing craft. The bright feature near the center of the image is Ovda Regio, a mountainous region in the western portion of the great Aphrodite equatorial highland. The dark areas scattered across the Venusian plains consist of extremely smooth deposits associated with large meteorite impacts. The image was produced by the Solar System Visualization Project and the Magellan Science team at the Jet Propulsion Laboratory Multimission Image Processing Laboratory. The Magellan mission is managed by JPL for NASA's Office of Space Science. Lots of information about Venus at http://www.nineplanets.org/venus.html
Primarily carbon dioxide about 10 miles high winds strong high in the atmosphere, but only slight breeze at surface sulfuric acid droplets atmospheric pressure at surface is 92 times Earth ’s reflects a lot of sunlight, making Venus appear bright (high albedo)
Information and statistics at http://www.nineplanets.org/earth.html
Information at http://www.nineplanets.org/mars.html Image caption: Global Mosaic of Mars Centered on Valles Marineris Date: 02.22.1980 Global mosaic of 102 Viking 1 Orbiter images of Mars taken on orbit 1,334, 22 February 1980. The images are projected into point perspective, representing what a viewer would see from a spacecraft at an altitude of 2,500 km. At center is Valles Marineris, over 3000 km long and up to 8 km deep. Note the channels running up (north) from the central and eastern portions of Valles Marineris to the dark area, Acidalic Planitia, at upper right. At left are the three Tharsis volcanoes and to the south is ancient, heavily impacted terrain. (Viking 1 Orbiter, MG07S078-334SP) Image Credit : NASA
Mars Rovers information at http://marsrovers.jpl.nasa.gov/home/index.html landed on Mars January 3 and January 24, 2004 Searched for rocks and soils that hold clues to past water activity on Mars The landing sites were Gusev Crater, a possible former lake in a giant impact crater, and Meridiani Planum, where mineral deposits (hematite) suggest Mars had a wet past. January 24, 2006 Mars Rovers Advance Understanding of the Red Planet NASA's Mars rovers, Spirit and Opportunity, have been working overtime to help scientists better understand ancient environmental conditions on the red planet. The rovers are also generating excitement about the exploration of Mars outlined in NASA's Vision for Space Exploration. The rovers continue to find new variations of bedrock in areas they are exploring on opposite sides of Mars. The geological information they have collected adds evidence about ancient Martian environments that included periods of wet, possibly habitable conditions. "The extended journeys taken by the two rovers across the surface of Mars has allowed the science community to continue to uncover discoveries that will enable new investigations of the red planet far into the future." said Mary Cleave, associate administrator for the Science Mission Directorate, NASA Headquarters. In late November 2005 while descending "Husband Hill," Spirit took the most detailed panorama to date of the "Inner Basin." Image credit: NASA/JPL/Cornell Large Image NASA's third mission extension for the rovers lasts through September 2006, if they remain usable that long. During their three-month primary missions, the rovers drove farther and examined more rocks than the prescribed criteria for success. Opportunity begins its third year on Mars today. It is examining bedrock exposures along a route between "Endurance" and "Victoria" craters. Opportunity found evidence of a long-ago habitat of standing water on Mars. On Jan. 3, Spirit passed its second anniversary inside the Connecticut-sized Gusev Crater. Initially, Spirit did not find evidence of much water, and hills that might reveal more about Gusev's past were still mere bumps on the horizon. By operating eight times as long as planned, Spirit was able to climb up those hills, examine a wide assortment of rocks and find mineral fingerprints of ancient water. While showing signs of wear, Spirit and Opportunity are still being used to their maximum remaining capabilities. On Spirit, the teeth of the rover's rock abrasion tool are too worn to grind the surface off any more rocks, but its wire-bristle brush can still remove loose coatings. The tool was designed to uncover three rocks, but it exposed interiors of 15 rocks. On Opportunity, the steering motor for the front right wheel stopped working eight months ago. A motor at the shoulder joint of the rover's robotic arm shows symptoms of a broken wire in the motor winding. Opportunity can still maneuver with its three other steerable wheels. Its shoulder motor still works when given extra current, and the arm is still useable without that motor. The rovers are two of five active robotic missions at Mars, which include NASA's Mars Odyssey and Mars Global Surveyor and the European Space Agency's Mars Express orbiters. The orbiters and surface missions complement each other in many ways. Observations by the rovers provide ground-level understanding for interpreting global observations by the orbiters. In addition to their own science missions, the orbiters relay data from Mars. NASA's Jet Propulsion Laboratory, Pasadena, Calif., a division of the California Institute of Technology, manages the Mars Exploration Rover, Odyssey and Global Surveyor projects for NASA's Science Mission Directorate.
Jupiter was first visited by Pioneer 10 in 1973 and later by Pioneer 11, Voyager 1, Voyager 2 and Ulysses. The spacecraft Galileo orbited Jupiter for eight years. It is still regularly observed by the Hubble Space Telescope. More information at http://www.nineplanets.org/jupiter.html
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. Image Credit: NASA/JPL/Malin Space Science Systems Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. Some radial structure is barely visible across the ring's ansa. A faint mist of particles can be seen above and below the main rings; this vertically extended "halo" is unusual in planetary rings, and is probably caused by electromagnetic forces pushing the smallest grains out of the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. Jupiter's main ring is a thin strand of material encircling the planet. The diffuse innermost boundary begins at approximately 123,000 km. The main ring's outer radius is found to be at 128,940 +/-50 km, slightly less than the Voyager value of 129,130 +/-100 km, but very close to the orbit of the satellite Adrastea (128,980 km). The main ring exhibits a marked drop in brightness at 127,849 +/-50 km, lying almost atop the orbit of the jovian moon Metis at 127,978 km. Satellites seem to affect the structure of even tenuous rings like that found at Jupiter. Image Note: Galileo Callisto 3 Orbit
Merger of white ovals over 3 years beginning in 1998 gave us Jr. Both storms wheel around the planet in longitude as Jupiter rotates, but are latitudinally locked in their own narrow bands in the southern hemisphere ABOUT THIS IMAGE: NASA's Hubble Space Telescope is giving astronomers their most detailed view yet of a second red spot emerging on Jupiter. For the first time in history, astronomers have witnessed the birth of a new red spot on the giant planet, which is located half a billion miles away. The storm is roughly one-half the diameter of its bigger and legendary cousin, the Great Red Spot. Researchers suggest that the new spot may be related to a possible major climate change in Jupiter's atmosphere. Dubbed by some astronomers as "Red Spot Jr.," the new spot has been followed by amateur and professional astronomers for the past few months. But Hubble's new images provide a level of detail comparable to that achieved by NASA's Voyager 1 and 2 spacecraft as they flew by Jupiter a quarter-century ago. Before it mysteriously changed to the same color as the Great Red Spot, the smaller spot was known as the White Oval BA. It formed after three white oval-shaped storms merged during 1998 to 2000. At least one or two of the progenitor white ovals can be traced back to 90 years ago, but they may have been present earlier. A third spot appeared in 1939. (The Great Red Spot has been visible for the past 400 years, ever since earthbound observers had telescopes to see it). When viewed at near-infrared wavelengths (specifically 892 nanometers — a methane gas absorption band) Red Spot Jr. is about as prominent in Jupiter's cloudy atmosphere as the Great Red Spot. This may mean that the storm rises miles above the top of the main cloud deck on Jupiter just as its larger cousin is thought to do. Some astronomers think the red hue could be produced as the spots dredge up material from deeper in Jupiter's atmosphere, which is then chemically altered by the Sun's ultraviolet light. Researchers think the Hubble images may provide evidence that Jupiter is in the midst of a global climate change that will alter its average temperature at some latitudes by as much as 10 degrees Fahrenheit. The transfer of heat from the equator to the planet's south pole is predicted to nearly shut off at 34 degrees southern latitude, the latitude where the second red spot is forming. The effects of the shut-off were predicted by Philip Marcus of the University of California, Berkeley (UCB) to become apparent approximately seven years after the White Oval collisions in 1998 to 2000. Two teams of astronomers were given discretionary time on Hubble to observe the new red spot. [Left] — This image, acquired April 8, 2006 with Hubble's Advanced Camera for Surveys (high-resolution channel), shows that the second red spot has a small amount of pale clouds in the center. A strong convective event, which is likely a thunderstorm, is visible as a bright white cloud north of the oval, in the turbulent clouds that precede the Great Red Spot. As the oval continues its eastward drift and the Great Red Spot moves westward, they should pass each other in early July. This contrast-enhanced image was taken in blue and red light. The group that performed this observation was led by Amy Simon-Miller (NASA Goddard Space Flight Center), Glenn Orton (Jet Propulsion Laboratory) and Nancy Chanover (New Mexico State University). [Right] — Hubble's Advanced Camera for Surveys (wide field channel) took this image of the entire disk of Jupiter on April 16. The second red spot appears at southern latitudes, below the center of Jupiter's disk. The new spot is approximately the size of Earth's diameter. The image was taken in visible light and at near-infrared wavelengths, and does not represent Jupiter's true colors. The red color traces high-altitude haze blankets: the equatorial zone, the Great Red Spot, the second red spot, and the polar hoods. The Hubble group that conducted this observation is led jointly by Imke de Pater (UCB Astronomy) and Philip Marcus (UCB Mechanical Engineering). Other team members are Michael Wong (UCB Astronomy), Xylar Asay-Davis (UCB Mechanical Engineering), and Christopher Go, an amateur astronomer with the Astronomical League of the Philippines.
155,000 miles in diameter / ½ mile thick – rings Saturn is the sixth planet from the Sun and the second largest: orbit: 1,429,400,000 km (9.54 AU) from Sun diameter: 120,536 km (equatorial) mass: 5.68e26 kg Ring image from http://saturn.jpl.nasa.gov/multimedia/images/image-details.cfm?imageID=849 More information at http://www.nineplanets.org/saturn.html
Information on Uranus at http://www.nineplanets.org/uranus.html
First telescopic discovery of a planet (Herschel; 1781) Original Caption Released with Image: These two pictures of Uranus were compiled from images recorded by Voyager 2 on Jan. 1O, 1986, when the NASA spacecraft was 18 million kilometers (11 million miles) from the planet. The images were obtained by Voyager's narrow-angle camera; the view is toward the planet's pole of rotation, which lies just left of center. The picture on the left has been processed to show Uranus as human eyes would see it from the vantage point of the spacecraft. The second picture is an exaggerated false-color view that reveals details not visible in the true-color view -- including indications of what could be a polar haze of smog-like particles. The true-color picture was made by combining pictures taken through blue, green and orange filters. The dark shading of the upper right edge of the disk is the terminator, or day-night boundary. The blue-green appearance of Uranus results from methane in the atmosphere; this gas absorbs red wavelengths from the incoming sunlight, leaving the predominant bluish color seen here. The picture on the right uses false color and contrast enhancement to bring out subtle details in the polar region of the atmosphere. Images shuttered through different color filters were added and manipulated by computer, greatly enhancing the low-contrast details in the original images. Ultraviolet, violet- and orange-filtered images were displayed, respectively, as blue, green and red to produce this false-color picture. The planet reveals a dark polar hood surrounded by a series of progressively lighter convective bands. The banded structure is real, though exaggerated here. The brownish color near the center of the planet could be explained as being caused by a thin haze concentrated over the pole -- perhaps the product of chemical reactions powered by ultraviolet light from the Sun. One such reaction produces acetylene from methane -- acetylene has been detected on Uranus by an Earth-orbiting spacecraft -- and further reactions involving acetylene are known to produce reddish-brown smog-like particles. A similar haze envelopes Saturn's moon Titan; ground-based observations have predicted such a haze in the polar regions of Uranus. The exact identification of the reactions and their products will require additional study. Voyager 2 is heading for a Jan. 24 closest approach to Uranus. The Voyager project is managed for NASA by the Jet Propulsion Laboratory. Image Note: blue - PICNO 0068U2-014 red - PICNO 0192U2-014 green - PICNO 0204U2-014
Original Caption Released with Rings Image: Voyager 2 returned this picture of the Uranus rings on Jan. 22, 1986, from a distance of 2.52 million kilometers (1.56 million miles). All nine known rings are visible in this image, a 15-second exposure through the clear filter on Voyager's narrow-angle camera. The rings are quite dark and very narrow. The most prominent and outermost of the nine, called epsilon, is seen at top. The next three in toward Uranus -- called delta, gamma and eta -- are much fainter and more narrow than the epsilon ring. Then come the beta and alpha rings and finally the innermost grouping, known simply as the 4, 5 and 6 rings. The last three are very faint and are at the limit of detection for the Voyager camera. Uranus' rings range in width from about 100 km (60 mi) at the widest part of the epsilon ring to only a few kilometers for most of the others. This image was processed to enhance these narrow features; the bright dots are imperfections on the camera detector. The resolution scale is approximately 50 km (30 mi). The Voyager project is managed for NASA by the Jet Propulsion Laboratory. Original Caption Released with Hubble Image of Uranus ’ Atmosphere: Hubble Space Telescope has peered deep into Uranus' atmosphere to see clear and hazy layers created by a mixture of gases. Using infrared filters, Hubble captured detailed features of three layers of Uranus' atmosphere. Hubble's images are different from the ones taken by the Voyager 2 spacecraft, which flew by Uranus 10 years ago. Those images - not taken in infrared light - showed a greenish-blue disk with very little detail. The infrared image allows astronomers to probe the structure of Uranus' atmosphere, which consists of mostly hydrogen with traces of methane. The red around the planet's edge represents a very thin haze at a high altitude. The haze is so thin that it can only be seen by looking at the edges of the disk, and is similar to looking at the edge of a soap bubble. The yellow near the bottom of Uranus is another hazy layer. The deepest layer, the blue near the top of Uranus, shows a clearer atmosphere. Image processing has been used to brighten the rings around Uranus so that astronomers can study their structure. In reality, the rings are as dark as black lava or charcoal. Bottom Hubble image: A recent Hubble Space Telescope view reveals Uranus surrounded by its four major rings and by 10 of its 17 known satellites. This false-color image was generated by Erich Karkoschka using data taken on August 8, 1998, with Hubble's Near Infrared Camera and Multi-Object Spectrometer. Hubble recently found about 20 clouds — nearly as many clouds on Uranus as the previous total in the history of modern observations. The orange-colored clouds near the prominent bright band circle the planet at more than 300 mph (500 km/h), according to team member Heidi Hammel (MIT). One of the clouds on the right-hand side is brighter than any other cloud ever seen on Uranus. The colors in the image indicate altitude. Team member Mark Marley (New Mexico State University) reports that green and blue regions show where the atmosphere is clear and sunlight can penetrate deep into Uranus. In yellow and grey regions the sunlight reflects from a higher haze or cloud layer. Orange and red colors indicate very high clouds, such as cirrus clouds on Earth. The Hubble image is one of the first images revealing the precession of the brightest ring with respect to a previous image [LINK to PRC97-36a]. Precession makes the fainter part of the ring (currently on the upper right-hand side) slide around Uranus once every nine months. The fading is caused by ring particles crowding and hiding each other on one side of their eight-hour orbit around Uranus. The blue, green and red components of this false-color image correspond to exposures taken at near-infrared wavelengths of 0.9, 1.1, and 1.7 micrometers. Thus, regions on Uranus appearing blue, for example, reflect more sunlight at 0.9 micrometer than at the longer wavelengths. Apparent colors on Uranus are caused by absorption of methane gas in its atmosphere, an effect comparable to absorption in our atmosphere which can make distant clouds appear red. Object Name: Uranus Image Type: Astronomical CREDIT: Erich Karkoschka (University of Arizona) and NASA
Information on Neptune at http://www.nineplanets.org/neptune.html Original Caption Released with Image: Neptune's blue-green atmosphere is shown in greater detail than ever before by the Voyager 2 spacecraft as it rapidly approaches its encounter with the giant planet. This color image, produced from a distance of about 16 million kilometers, shows several complex and puzzling atmospheric features. The Great Dark Spot (GDS) seen at the center is about 13,000 km by 6,600 km in size -- as large along its longer dimension as the Earth. The bright, wispy "cirrus-type" clouds seen hovering in the vicinity of the GDS are higher in altitude than the dark material of unknown origin which defines its boundaries. A thin veil often fills part of the GDS interior, as seen on the image. The bright cloud at the southern (lower) edge of the GDS measures about 1,000 km in its north-south extent. The small, bright cloud below the GDS, dubbed the "scooter," rotates faster than the GDS, gaining about 30 degrees eastward (toward the right) in longitude every rotation. Bright streaks of cloud at the latitude of the GDS, the small clouds overlying it, and a dimly visible dark protrusion at its western end are examples of dynamic weather patterns on Neptune, which can change significantly on time scales of one rotation (about 18 hours). Image Note: Green - PICNO 1736N2-012Blue - PICNO 1742N2-012Red - PICNO 1749N2-012
Original Caption Released with Image: Neptune's blue-green atmosphere is shown in greater detail than ever before by the Voyager 2 spacecraft as it rapidly approaches its encounter with the giant planet. This color image, produced from a distance of about 16 million kilometers, shows several complex and puzzling atmospheric features. The Great Dark Spot (GDS) seen at the center is about 13,000 km by 6,600 km in size -- as large along its longer dimension as the Earth. The bright, wispy "cirrus-type" clouds seen hovering in the vicinity of the GDS are higher in altitude than the dark material of unknown origin which defines its boundaries. A thin veil often fills part of the GDS interior, as seen on the image. The bright cloud at the southern (lower) edge of the GDS measures about 1,000 km in its north-south extent. The small, bright cloud below the GDS, dubbed the "scooter," rotates faster than the GDS, gaining about 30 degrees eastward (toward the right) in longitude every rotation. Bright streaks of cloud at the latitude of the GDS, the small clouds overlying it, and a dimly visible dark protrusion at its western end are examples of dynamic weather patterns on Neptune, which can change significantly on time scales of one rotation (about 18 hours). Image Note: Green - PICNO 1736N2-012Blue - PICNO 1742N2-012Red - PICNO 1749N2-012 This bulls-eye view of Neptune's small dark spot (D2) was obtained by Voyager 2's narrow-angle camera. Banding surrounding the feature indicates unseen strong winds, while structures within the bright spot suggest both active upwelling of clouds and rotation about the center. A rotation rate has not yet been measured, but the V-shaped structure near the right edge of the bright area indicates that the spot rotates clockwise. Unlike the Great Red Spot on Jupiter, which rotates counterclockwise, if the D2 spot on Neptune rotates clockwise, the material will be descending in the dark oval region. The fact that infrared data will yield temperature information about the region above the clouds makes this observation especially valuable. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. Image Note: PICNO 0441N2-001
More information at http://www.lpi.usra.edu/education/explore/comets/ What does a comet nucleus look like? Formed from the primordial stuff of the solar system, it is thought to resemble a very dirty iceberg. But for active comets, telescopic images only reveal the surrounding cloud of gas and dust, the comet's coma, and the characteristic cometary tails. In 1986, the European spacecraft Giotto encountered the nucleus of Halley's comet as it approached the sun. Data from Giotto's camera was used to generate this enhanced image of the potato shaped nucleus which measures roughly 15 kilometers across. It shows surface features on the dark nucleus against the bright background of the coma as the icy material is vaporized by the Sun's heat. Every 76 years Comet Halley returns to the inner solar system and each time the nucleus sheds about a 6 meter deep layer of its ice and rock into space. This debris composes Halley's tails and leaves an orbiting trail responsible for the Orionids meteor shower.
From http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=2167 This is a montage of planetary images taken by spacecraft. Included are (from top to bottom) Mercury, Venus, Earth (and Moon), Mars, Jupiter, Saturn,Uranus and Neptune. The spacecraft responsible for these images are as follows: Mercury was photographed by Mariner 10. Venus was imaged by the Magellan spacecraft's radar. Earth and its Moon were photographed by Galileo. Mars Global Surveyor took the image of Mars. Jupiter was photographed by Cassini as it traveled to Saturn. Saturn, Uranus and Neptune images were taken by the twin Voyager spacecraft. Pluto is not shown. No spacecraft has visited Pluto and it is too small and distant for good photography. 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. But the actual size differences between the inner and outer planets is not to scale. Actual diameters: 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
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