1221 Amor
 Orbit of 1221 Amor on 1932-03-12: yellow - Sun, green - Earth, red - Mars, light blue - Amor, dark blue - Jupiter | |
| Discovery | |
|---|---|
| Discovered by | Eugène Joseph Delporte |
| Discovery site | Uccle |
| Discovery date | 12 March 1932 |
| Designations | |
| 1932 EA1 | |
|
Amor II asteroid, Mars-crosser asteroid | |
| Orbital characteristics[1] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 83.52 yr (30505 days) |
| Aphelion | 2.7551 AU (412.16 Gm) |
| Perihelion | 1.0833 AU (162.06 Gm) |
| 1.9192 AU (287.11 Gm) | |
| Eccentricity | 0.43554 |
| 2.66 yr (971.16 d) | |
Average orbital speed | 20.44 km/s |
| 239.60° | |
| 0° 22m 14.484s / day | |
| Inclination | 11.880° |
| 171.346° | |
| 26.647° | |
| Earth MOID | 0.10617 AU (15.883 Gm) |
| Jupiter MOID | 2.21512 AU (331.377 Gm) |
| Jupiter Tisserand parameter | 3.781 |
| Proper orbital elements[1][2] | |
Proper eccentricity | 0.439 |
Proper inclination | 11.096° |
Proper mean motion | 135.281 deg / yr |
Proper orbital period |
2.66113 yr (971.977 d) |
| Physical characteristics | |
| Dimensions | 1 km (0.62 mi) |
Mean radius | 0.5 km |
| Mass | 3.5×1012 kg |
Mean density | 2? g/cm³ |
Equatorial surface gravity | 0.000 42 m/s² |
Equatorial escape velocity | 0.000 79 km/s |
| 0.15? | |
| Temperature | ~198 K |
| C or S | |
| 17.7 | |
|
| |
1221 Amor is the namesake of the Amor asteroids, a group of near-Earth asteroids whose orbits range between those of Earth and Mars. Amors are often Mars-crossers but they are not Earth-crossers.
Eugène Joseph Delporte photographed Amor as it approached Earth to within 16 million kilometers (about 40 times the distance from Earth to the moon); this was the first time that an asteroid was seen to approach Earth so closely. A month later, 1862 Apollo was seen to cross Earth's orbit, and the scientific community suddenly realised the potential threat these flying mountains presented.
Amor is named after the Roman god of love, better known as Cupid.[3] See also 763 Cupido and 433 Eros, which is named after Cupid's Greek counterpart. Coincidentally, 433 Eros, like 1221 Amor, makes close approaches to Earth. It is a Mars-crosser as well.
References
- 1 2 "1221 Amor". JPL Small-Body Database. Jet Propulsion Laboratory. SPK-ID: 1221. Retrieved 30 April 2016.
- ↑ "(1221) Amor". NEODyS. University of Pisa. Retrieved 27 November 2015.
- ↑ Schmadel, Lutz D. (2003). Dictionary of Minor Planet Names. Springer. p. 100. ISBN 3-540-00238-3.
External links
- 1221 Amor at the JPL Small-Body Database
