1620 Geographos
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A three-dimensional model of 1620 Geographos based on its light curve
|
|
| Discovery | |
|---|---|
| Discovered by | Albert George Wilson, Rudolph Minkowski |
| Discovery date | September 14, 1951 |
| Designations | |
|
Named after
|
National Geographic Society |
| 1951 RA | |
| Apollo, PHA,[1] Mars-crosser | |
| Orbital characteristics[1] | |
| Epoch March 6, 2006 (JD 2453800.5) | |
| Aphelion | 1.663 AU (248.810 Gm) |
| Perihelion | 0.828 AU (123.817 Gm) |
| 1.245 AU (186.314 Gm) | |
| Eccentricity | 0.335 |
| 1.39 yr (507.665 d) | |
|
Average orbital speed
|
25.92 km/s |
| 147.839° | |
| Inclination | 13.341° |
| 337.293° | |
| 276.793° | |
| Physical characteristics | |
| Dimensions | 5.1×1.8 km[1] |
| 0.217 d (5.223 h)[1] | |
| Albedo | 0.325[1] |
| Temperature | ~249 K |
|
Spectral type
|
S[1] |
| 15.60[1] | |
The asteroid 1620 Geographos /dʒiːoʊˈɡræfɒs/ was discovered on September 14, 1951, at the Palomar Observatory by Albert George Wilson and Rudolph Minkowski. It was originally given the provisional designation 1951 RA. Its name, a Greek word meaning "geographer" (geo– 'Earth' + graphos 'drawer/writer'), was chosen to honour geographers and the National Geographic Society.
Geographos is a Mars-crosser asteroid and a near-Earth object belonging to the Apollos. In 1994, during the asteroid's closest approach to Earth in two centuries at 5.0 Gm-which will not be bettered until 2586- a radar study of it was conducted by the Deep Space Network at Goldstone, California. The resultant images show Geographos to be the most elongated object in the solar system; it measures 5.1×1.8 km.
Geographos is an S-type asteroid, meaning that it is highly reflective and composed of nickel-iron mixed with iron- and magnesium-silicates.
Geographos was to be explored by the U.S.'s Clementine mission; however, a malfunctioning thruster ended the mission before it could approach the asteroid.
1620 Geographos is a potentially hazardous asteroid (PHA) because its minimum orbit intersection distance (MOID) is less than 0.05 AU and its diameter is greater than 150 meters. The Earth-MOID is 0.0304 AU (4,550,000 km; 2,830,000 mi).[1] Its orbit is well-determined for the next several hundred years.
