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Theseus taking off at Edward
…
A Radar Image of Venus
| Title |
A Radar Image of Venus |
| Explanation |
The largest radio telescopes in the world are working together to create a new map of the surface of Venus. The surface of Venus [ http://www.nineplanets.org/venus.html ] is unusually hidden by a thick atmosphere [ http://bigmac.civil.mtu.edu/public_html/classes/ce459/projects/t15/r15.html ] of mostly carbon dioxide [ http://scifun.chem.wisc.edu/chemweek/CO2/CO2.html ] gas. These thick clouds [ http://antwrp.gsfc.nasa.gov/apod/ap960923.html ] are transparent, however, to radar signals [ http://spaceplace.jpl.nasa.gov/srtm_makemap3.htm ] sent and received from Earth. The two radio telescopes [ http://www.setileague.org/otherweb/othrtele.htm ] generating the most powerful radar ever are the Arecibo Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap981129.html ] in Puerto Rico [ http://www.cia.gov/cia/publications/factbook/geos/rq.html ] and the new Robert C. Byrd Green Bank Telescope [ http://www.gb.nrao.edu/GBT/GBT.html ] in West Virginia [ http://www.state.wv.us/ ]. The new survey will resolve details as fine a one-kilometer across, and will be inspected for changes since the last major radar map [ http://antwrp.gsfc.nasa.gov/apod/ap991128.html ] was made by NASA's Magellan spacecraft [ http://www.jpl.nasa.gov/magellan/ ] that orbited Venus [ http://antwrp.gsfc.nasa.gov/apod/venus.html ] from 1990 to 1994. Pictured above [ http://www.aoc.nrao.edu/pr/gbtfirstsci.html ] is part of a preliminary image showing details as small as five-kilometers across. |
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Asteroid 2007 TU24 Passes th
…
| Title |
Asteroid 2007 TU24 Passes the Earth |
| Explanation |
Asteroid 2007 TU24 passed by the Earth yesterday, posing no danger. The space rock, estimated [ http://www.nasa.gov/topics/solarsystem/features/asteroid-20080125.html ] to be about 250 meters across, coasted by just outside the orbit of Earth's Moon. The passing was not very unusual [ http://antwrp.gsfc.nasa.gov/apod/ap050417.html ] -- small rocks strike Earth daily, and in 2003 a rock the size of a bus passed inside the orbit of the Moon, being detected only after passing [ http://antwrp.gsfc.nasa.gov/apod/ap031015.html ]. TU24 was notable partly because it was so large. Were TU24 [ http://en.wikipedia.org/wiki/TU24 ] to have struck land, it might have caused a magnitude [ http://www.geo.mtu.edu/UPSeis/magnitude.html ] seven earthquake [ http://www.youtube.com/watch?v=19fMs633Td4 ] and left a city-sized crater [ http://antwrp.gsfc.nasa.gov/apod/ap990711.html ]. A perhaps larger danger would have occurred were TU24 [ http://www.planetary.org/blog/article/00001309/ ] to have struck the ocean and raised a large tsunami [ http://en.wikipedia.org/wiki/Tsunami ]. This radar image [ http://www.jpl.nasa.gov/news/news.cfm?release=2008-014 ] was taken two days ago. The Arecibo Radio Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap981129.html ] in Puerto Rico [ http://en.wikipedia.org/wiki/Puerto_Rico ] broadcast radar that was reflected by the asteroid and then recorded by the Byrd Radio Telescope [ http://www.gb.nrao.edu/gbt/ ] in Green Bank [ http://www.nrao.edu/administration/personnel_office/greenbank.shtml ], West Virginia [ http://en.wikipedia.org/wiki/West_Virginia ]. The resulting image [ http://www.jpl.nasa.gov/news/news.cfm?release=2008-014 ] shows TU24 to have an oblong and irregular shape. TU24 [ http://www.nasa.gov/topics/solarsystem/features/asteroid-20080128-clips.html ] was discovered only three months ago, indicating that other potentially hazardous asteroids [ http://neo.jpl.nasa.gov/ca/ ] might lurk in our Solar System [ http://space.jpl.nasa.gov/ ] currently undetected. Objects like TU24 [ http://www.space.com/scienceastronomy/080128-asteroid-radar.html ] are hard to detect because they are so faint and move [ http://antwrp.gsfc.nasa.gov/apod/ap060328.html ] so fast. Humanity's ability to scan the sky to detect, catalog, and analyze such objects has increased notably [ http://www.lpl.arizona.edu/css/ ] in recent years. |
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First Snow in US Northeast:
…
nasa, nasanaturalhazards
A string of storms brought t
…
UnitedStates_TMO_2007340
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-12-06 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
UnitedStates_TMO_2007340 |
|
Coal Sludge Impoundments, We
…
nasa, nasaimageofthedaygalle
…
Since the mid- to late 1990s
…
wvslurry_iko_2006076
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2006-03-18 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
wvslurry_iko_2006076 |
|
Hobet-21 Mine, West Virginia
…
nasa, nasaimageofthedaygalle
…
Over the past two decades, t
…
hobet_mine
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
hobet_mine |
|
Hobet-21 Mine, West Virginia
…
nasa, nasaimageofthedaygalle
…
Over the past two decades, t
…
hobet_mine
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
hobet_mine |
|
Mining Permits across West V
…
nasa, nasaimageofthedaygalle
…
In 2005, the U.S. Environmen
…
wva_mines_tmo_lrg
| mediatype |
IMAGE |
| mediatype |
image |
| date |
2007-09-29 |
| creator |
NASA -- NASA Image Of The Day |
| identifier |
wva_mines_tmo_lrg |
|
Sri Lanka, Colored Height
PIA06670
Sol (our sun)
C-Band Interferometric Radar
| Title |
Sri Lanka, Colored Height |
| Original Caption Released with Image |
The topography of the island nation of Sri Lanka is well shown in this color-coded shaded relief map generated with digital elevation data from the Shuttle Radar Topography Mission (SRTM). Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction, so that northwest slopes appear bright and southeast slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations. For this special view heights below 10 meters (33 feet) above sea level have been colored red. These low coastal elevations extend 5 to 10 km (3.1 to 6.2 mi) inland on Sri Lanka and are especially vulnerable to flooding associated with storm surges, rising sea level, or, as in the aftermath of the earthquake of December 26, 2004, tsunami. These so-called tidal waves have occurred numerous times in history and can be especially destructive, but with the advent of the near-global SRTM elevation data planners can better predict which areas are in the most danger and help develop mitigation plans in the event of particular flood events. Sri Lanka is shaped like a giant teardrop falling from the southern tip of the vast Indian subcontinent. It is separated from India by the 50km (31mi) wide Palk Strait, although there is a series of stepping-stone coral islets known as Adam's Bridge that almost form a land bridge between the two countries. The island is just 350km (217mi) long and only 180km (112mi) wide at its broadest, and is about the same size as Ireland, West Virginia or Tasmania. The southern half of the island is dominated by beautiful and rugged hill country, and includes Mt Pidurutalagala, the islandâ??s highest point at 2524 meters (8281 ft). The entire northern half comprises a large plain extending from the edge of the hill country to the Jaffna peninsula. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Earth Science Enterprise,Washington, D.C. Location: 8.0 degrees North latitude, 80.7 degrees East longitude Orientation: North, toward the top, Mercator projection Size: 275.6 by 482.4 kilometers (165.4 by 299.0 miles) Image Data: shaded and colored SRTM elevation model Date Acquired: February 2000 |
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| General Description |
STS-73 Shuttle Mission Imagery |
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