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Kennedy Space Center, Florid
…
This is an X-band Synthetic
…
10/10/94
| Date |
10/10/94 |
| Description |
This is an X-band Synthetic Aperture Radar image spanning an area of about 20 kilometers by 40 kilometers (12 miles by 25 miles) of the Kennedy Space Center, Florida. At the top right are cloud-like structures which indicate rain. X-SAR is able to image heavy rainfall. The Atlantic Ocean is at the upper right. The shuttle landing strip is seen at the top left of the image. The Vertical Assembly Building, the Orbiter Processing Facility and other associated buildings are seen as a white area to the right and just above the end of the shuttle strip. The shuttle launch pads are the two white areas near the top center of the image. The Banana River shows up as a large black area running north to south to the right of the image. The Indian River is on the left side of the image. Just above the image center is a cluster of white spots which are the major buildings of the Kennedy Space Center industrial area. This was the location of the reflector array that was constructed to form the letters "KSC" by the KSC payload team. The data for these KSC images were taken on orbit 81 of the space shuttle Endeavour on the fourth day of the SIR-C/X-SAR mission. ----- Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves, allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by NASA's Jet Propulsion Laboratory. X-SAR was developed by the Dornier and Alenia Spazio companies for the German space agency, Deutsche Agentur fuer Raumfahrtangelegenheiten (DARA), and the Italian space agency, Agenzia Spaziale Italiana (ASI), with the Deutsche Forschungsanstalt fuer Luft und Raumfahrt e.V.(DLR), the major partner in science, operations and data processing of X-SAR. ##### |
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Jane Houston Jones and Teles
…
| Description |
Jane Houston Jones and Telescope |
| Full Description |
Jane Houston Jones shows off her homemade Dobsonian reflector telescope she'll be pointing at Saturn in the coming months. Credit: Morris Jones |
| Date |
February 7, 2007 |
|
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 |
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Deep Space Network
| title |
Deep Space Network |
| description |
The NASA Deep Space Network - or DSN - is an international network of antennas that supports interplanetary spacecraft missions and radio and radar astronomy observations for the exploration of the solar system and the universe. The network also supports selected Earth-orbiting missions. The DSN currently consists of three deep-space communications facilities placed approximately 120 degrees apart around the world: at Goldstone, in California's Mojave Desert, near Madrid, Spain, and near Canberra, Australia. This strategic placement permits constant observation of spacecraft as the Earth rotates, and helps to make the DSN the largest and most sensitive scientific telecommunications system in the world. NASA's scientific investigation of the Solar System is being accomplished mainly through the use of unmanned automated spacecraft. The DSN provides the vital two-way communications link that guides and controls these planetary explorers, and brings back the images and new scientific information they collect. All DSN antennas are steerable, high-gain, parabolic reflector antennas. The network is managed and operated for NASA by the Jet Propulsion Laboratory. The Interplanetary Network Directorate (IND) manages the program within JPL. For more on the Deep Space Network, visit http://deepspace.jpl.nasa.gov/dsn/index.html *Image Credit*: NASA |
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A Hale-Bopp Triple Crown
| Title |
A Hale-Bopp Triple Crown |
| Explanation |
It was truly a busy sky. In one of the more spectacular photos yet submitted to Astronomy Picture of the Day [ http://www.phy.mtu.edu/apod/ ], Don Cooke of Lyme, New Hampshire [ http://www.state.nh.us/soiccnh/lyme.htm ] caught the Sun [ http://www.seds.org/nineplanets/nineplanets/sol.html ], Moon [ http://antwrp.gsfc.nasa.gov/apod/lib/moon.html ], Earth [ http://antwrp.gsfc.nasa.gov/apod/ap970130.html ], night sky [ http://antwrp.gsfc.nasa.gov/apod/ap970403.html ], Pleiades star cluster [ http://antwrp.gsfc.nasa.gov/apod/ap960903.html ], and Comet Hale-Bopp [ http://www.jpl.nasa.gov/comet/ ] all in one frame. The first leg of this "triple crown" exposure was of the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap960518.html ], taken at 6:55 pm on April 10th 1997. Through a dark filter, the Sun [ http://antwrp.gsfc.nasa.gov/apod/lib/sun.html ] appears as the bright dot on the lower right of the image. A second filtered exposure was then taken after the Sun had set, one hour and 40 minutes later - this time featuring the Moon [ http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-moon.html ]. The Moon appears as a crescent superimposed on an odd-shaped dark circle protruding into the left of the image. This shadow is actually a silhouette of a driveway reflector mounted on an aluminum rod used to block out the bright moon - so as to allow a third exposure, this time unfiltered, of the background night sky. And what a beautiful sky it is. Highlights include Comet Hale-Bopp [ http://antwrp.gsfc.nasa.gov/apod/ap970610.html ], on the right, and the Pleiades star cluster [ http://www.seds.org/billa/twn/m45x.html ], near the center. But what, you may wonder, is that bright light near the center of the picture? Don't worry if you can't guess: it's a porch light from a house across the river! |
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Radargrams of Buried Basin f
…
| title |
Radargrams of Buried Basin from Two Adjacent Orbits |
| Description |
These two radargrams from the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) show echoes from an approximately 250-kilometer (155-mile) diameter circular structure below the surface of Mars. The circular structure is interpreted to be a buried impact basin. In two orbits spaced about 50 kilometers (31 miles) apart, MARSIS detected a series of arc-shaped reflectors that have no apparent source in the surface topography or geology. In the lower image, a linear reflector nearly parallel to the surface is seen embedded in the arcs. This reflection may be coming from the floor of the basin. The time delay to the linear reflector suggests a depth of 1.5 to 2.5 kilometers (0.9 to 1.6 miles). MARSIS is an instrument on the European Space Agency's Mars Express orbiter. NASA and the Italian Space Agency jointly funded the instrument. Credit: ASI/NASA/ESA/Univ. of Rome/JPL |
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Interpreting Radar View near
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PIA09076
Sol (our sun)
Shallow Subsurface Radar (SH
…
| Title |
Interpreting Radar View near Mars' South Pole, Orbit 1334 |
| Original Caption Released with Image |
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter is shown in the upper-right panel and reveals detailed structure in the polar layered deposits of the south pole of Mars. The sounding radar collected the data presented here during orbit 1334 of the mission, on Nov. 8, 2006. The horizontal scale in the radargram is distance along the ground track. It can be referenced to the ground track map shown in the lower right. The radar traversed from about 75 to 85 degrees south latitude, or about 590 kilometers (370 miles). The ground track map shows elevation measured by the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter. Green indicates low elevation, reddish-white indicates higher elevation. The traverse proceeds up onto a plateau formed by the layers. The vertical scale on the radargram is time delay of the radar signals reflected back to Mars Reconnaissance Orbiter from the surface and subsurface. For reference, using an assumed velocity of the radar waves in the subsurface, time is converted to depth below the surface at one place: about 1,500 meters (5,000 feet) to one of the deeper subsurface reflectors. The color scale varies from black for weak reflections to white for strong reflections. The middle panel shows mapping of the major subsurface reflectors, some of which can be traced for a distance of 100 kilometers (60 miles) or more. The layers are not all horizontal and the reflectors are not always parallel to one another. Some of this is due to variations in surface elevation, which produce differing velocity path lengths for different reflector depths. However, some of this behavior is due to spatial variations in the deposition and removal of material in the layered deposits, a result of the recent climate history of Mars. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington. |
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Interpreting Radar View near
…
PIA09075
Sol (our sun)
Shallow Subsurface Radar (SH
…
| Title |
Interpreting Radar View near Mars' South Pole, Orbit 1360 |
| Original Caption Released with Image |
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter is shown in the upper-right panel and reveals detailed structure in the polar layered deposits of the south pole of Mars. The sounding radar collected the data presented here during orbit 1360 of the mission, on Nov. 10, 2006. The horizontal scale in the radargram is distance along the ground track. It can be referenced to the ground track map shown in the lower right. The radar traversed from about 74 degrees to 85 degrees south latitude, or about 650 kilometers (400 miles). The ground track map shows elevation measured by the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter. Green indicates low elevation, reddish-white indicates higher elevation. The traverse proceeds up onto a plateau formed by the layers. The vertical scale on the radargram is time delay of the radar signals reflected back to Mars Reconnaissance Orbiter from the surface and subsurface. For reference, using an assumed velocity of the radar waves in the subsurface, time is converted to depth below the surface at one place: about 800 meters (2,600 feet) to one of the strongest subsurface reflectors. This reflector marks the base of the polar layered deposits. The color scale varies from black for weak reflections to white for strong reflections. The middle panel shows mapping of the major subsurface reflectors, some of which can be traced for a distance of 100 kilometers (60 miles) or more. The layering manifests the recent climate history of Mars, recorded by the deposition and removal of ice and dust. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington. |
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Interpreting Radar View near
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PIA09096
Sol (our sun)
Shallow Subsurface Radar (SH
…
| Title |
Interpreting Radar View near Mars' South Pole, Orbit 1334 |
| Original Caption Released with Image |
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter is shown in the upper-right panel and reveals detailed structure in the polar layered deposits of the south pole of Mars. The sounding radar collected the data presented here during orbit 1334 of the mission, on Nov. 8, 2006. The horizontal scale in the radargram is distance along the ground track. It can be referenced to the ground track map shown in the lower right. The radar traversed from about 75 to 85 degrees south latitude, or about 590 kilometers (370 miles). The ground track map shows elevation measured by the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor orbiter. Green indicates low elevation, reddish-white indicates higher elevation. The traverse proceeds up onto a plateau formed by the layers. The vertical scale on the radargram is time delay of the radar signals reflected back to Mars Reconnaissance Orbiter from the surface and subsurface. For reference, using an assumed velocity of the radar waves in the subsurface, time is converted to depth below the surface at one place: about 1,500 meters (5,000 feet) to one of the deeper subsurface reflectors. The color scale varies from black for weak reflections to white for strong reflections. The middle panel shows mapping of the major subsurface reflectors, some of which can be traced for a distance of 100 kilometers (60 miles) or more. The layers are not all horizontal and the reflectors are not always parallel to one another. Some of this is due to variations in surface elevation, which produce differing velocity path lengths for different reflector depths. However, some of this behavior is due to spatial variations in the deposition and removal of material in the layered deposits, a result of the recent climate history of Mars. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington. |
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Radar View of Layering near
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PIA09073
Sol (our sun)
Shallow Subsurface Radar (SH
…
| Title |
Radar View of Layering near Mars' South Pole, Orbit 1360 |
| Original Caption Released with Image |
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter reveals detailed structure in the polar layered deposits of Mars' south pole. The horizontal scale of the radargram is distance along the orbiter's ground track, about 650 kilometers (400 miles) from about 74 degrees south latitude on the left to about 85 degrees south latitude at right. The vertical scale is time delay of radar signals reflected back to the spacecraft from the surface and subsurface. For reference, the white double-headed arrow indicates a distance of about 800 meters (2,600 feet) between one of the strongest subsurface reflectors and ground level, based on an assumed velocity of the radar waves in the subsurface. This reflector marks the base of the polar layered deposits. The color scale varies from black for weak reflections to white for strong reflections. The sounding radar collected the data presented here during orbit 1360 of the mission, on Nov. 10, 2006. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington. |
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Radar View of Layering near
…
PIA09095
Sol (our sun)
Shallow Subsurface Radar (SH
…
| Title |
Radar View of Layering near Mars' South Pole, Orbit 1360 |
| Original Caption Released with Image |
A radargram from the Shallow Subsurface Radar instrument (SHARAD) on NASA's Mars Reconnaissance Orbiter reveals detailed structure in the polar layered deposits of Mars' south pole. The horizontal scale of the radargram is distance along the orbiter's ground track, about 650 kilometers (400 miles) from about 74 degrees south latitude on the left to about 85 degrees south latitude at right. The vertical scale is time delay of radar signals reflected back to the spacecraft from the surface and subsurface. For reference, the white double-headed arrow indicates a distance of about 800 meters (2,600 feet) between one of the strongest subsurface reflectors and ground level, based on an assumed velocity of the radar waves in the subsurface. This reflector marks the base of the polar layered deposits. The color scale varies from black for weak reflections to white for strong reflections. The sounding radar collected the data presented here during orbit 1360 of the mission, on Nov. 10, 2006. The Shallow Subsurface Radar was provided by the Italian Space Agency (ASI). Its operations are led by the University of Rome and its data are analyzed by a joint U.S.-Italian science team. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter for the NASA Science Mission Directorate, Washington. |
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Radargrams of Buried Basin f
…
PIA03236
Sol (our sun)
Mars Advanced Radar for Subs
…
| Title |
Radargrams of Buried Basin from Two Adjacent Orbits |
| Original Caption Released with Image |
These two radargrams from the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) show echoes from an approximately 250-kilometer (155-mile) diameter circular structure below the surface of Mars. The circular structure is interpreted to be a buried impact basin. In two orbits spaced about 50 kilometers (31 miles) apart, MARSIS detected a series of arc-shaped reflectors that have no apparent source in the surface topography or geology. In the lower image, a linear reflector nearly parallel to the surface is seen embedded in the arcs. This reflection may be coming from the floor of the basin. The time delay to the linear reflector suggests a depth of 1.5 to 2.5 kilometers (0.9 to 1.6 miles). MARSIS is an instrument on the European Space Agency's Mars Express orbiter. NASA and the Italian Space Agency jointly funded the instrument. |
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