|
|
22 Miles From Eros
| Title |
22 Miles From Eros |
| Explanation |
Last month the NEAR Shoemaker [ http://near.jhuapl.edu/NEAR/Education/model.html ] spacecraft swooped closer [ http://near.jhuapl.edu/NEAR/news/flash/00jul07_1.html ] to Eros, orbiting only 22 miles (36 kilometers) from [ http://antwrp.gsfc.nasa.gov/apod/ap980919.html ] the center of the asteroid. These two images taken on July 19 (left) [ http://near.jhuapl.edu/NEAR/iod/20000801/index.html ] and July 24 (right) [ http://near.jhuapl.edu/NEAR/iod/20000731/index.html ] reveal the diminutive world's [ http://antwrp.gsfc.nasa.gov/apod/ap000224.html ] pocked and mottled surface in amazing detail, showing features as small as 19 feet (6 meters) across. Eros is thought to be a primordial [ http://www.jhuapl.edu/public/pr/000530.htm ], undifferentiated asteroid [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ asteroids.html ] based on X-ray and gamma-ray [ http://near.jhuapl.edu/news/sci_updates/00jun20.html ] studies of its surface composition. In the left picture, its surface layer or regolith [ http://near.jhuapl.edu/news/sci_updates/00jul05.html ] is seen to be laced with bright and dark regions while in the right hand image dark regolith appears [ http://near.jhuapl.edu/NEAR/iod/20000707/index.html ] to have filled in some crater floors. The left and right images span an area about 2,600 feet (800 meters) and 3,000 ft (900 meters) wide respectively. On July 31, NEAR Shoemaker returned to [ http://near.jhuapl.edu/news/flash/00aug01_1.html ] its familiar 31 mile (50 kilometer) orbit, circling [ http://www.jpl.nasa.gov/basics/orbits.htm#orbits ] Eros serenely at about 6 miles per hour. |
|
Eros At Sunset
| Title |
Eros At Sunset |
| Explanation |
Gleaming in the rays of the setting sun, boulders litter the rugged surface of asteroid 433 Eros [ http://near.jhuapl.edu/eros/ ]. The brightest boulder, at the edge of the large, shadowy crater near this picture's bottom center, is about 30 meters (100 feet) across. In orbit around Eros since February 2000, the NEAR Shoemaker [ http://near.jhuapl.edu/NEAR/ ] spacecraft's camera recorded the dramatic view [ http://near.jhuapl.edu/NEAR/iod/20000821/index.html ] earlier this month from an altitude of about 50 kilometers. Eros itself orbits [ http://www.fwkc.com/encyclopedia/low/articles/o/ o018000416f.html ] the Sun with a perihelion [ http://imagine.gsfc.nasa.gov/docs/ dictionary.html#perihelion ] of 1.13 Astronomical Units [ http://imagine.gsfc.nasa.gov/docs/ask_astro/ answers/980122b.html ] (AU) and aphelion [ http://imagine.gsfc.nasa.gov/docs/ dictionary.html#aphelion ] of 1.78 AU. Part of a class of near-Earth asteroids [ http://neo.jpl.nasa.gov/neo.html ], it spends much of its time between the orbits of Mars (at 1.5 AU) and Earth (at 1 AU) ... but it wasn't always that way. Eros and other near-Earth asteroids [ http://neo.planetary.org/ABCsOfNEOs/index.html ] originally orbited in the main asteroid belt [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ asteroids.html ], between Jupiter [ http://galileo.jpl.nasa.gov/jupiter/jupiter.html ] and Mars [ http://nssdc.gsfc.nasa.gov/planetary/factsheet/ marsfact.html ]. Over time, the gravitational influence of Jupiter and other planets perturbed their orbits sending them on trajectories closer [ http://antwrp.gsfc.nasa.gov/apod/ap000226.html ] to Earth. |
|
Common Craters (Earth and Er
…
PIA02953
Sol (our sun)
Multi-Spectral Imager
| Title |
Common Craters (Earth and Eros) |
| Original Caption Released with Image |
The late Dr. Eugene Shoemaker, who many consider the founder of modern planetary science, did pioneering work at Meteor Crater, Arizona, documenting the effects of impact cratering as a planetary process. When part of a comet or asteroid strikes a planet or another asteroid, the resulting shock wave and excavation of rock and soil leave a characteristic landform that looks much the same from planet to planet, asteroid to asteroid. To illustrate the point, this NEAR Shoemaker image of a crater on Eros (left), taken July 6, 2000, from an orbital altitude of 50 kilometers (31 miles), is displayed next to and at approximately the same scale as Meteor Crater. Built and managed by The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery Program of low-cost, small-scale planetary missions. See the NEAR web page at http://near.jhuapl.edu for more details. |
|
|
