Discovered by E. Delporte MPC designation 2101 Adonis Minor planet category Apollo · NEO · PHA Discovered 12 February 1936 Orbits Sun | Discovery date 12 February 1936 Alternative names 1936 CA Orbital period 935 days Aphelion 3.31 m Discoverer Eugène Joseph Delporte | |
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Similar 4769 Castalia, 1862 Apollo, 54509 YORP, 588 Achilles, 19521 Chaos | ||
2101 Adonis, provisional designation 1936 CA, is an extremely eccentric asteroid, classified as near-Earth object and potentially hazardous asteroid. It belongs to the group of Apollo asteroids and measures approximately 1 kilometer in diameter. The asteroid was discovered on 12 February 1936, by Belgian astronomer Eugène Delporte at the Royal Observatory of Belgium in Uccle. It may also be an extinct comet and a source of meteor showers.
It was one of the first near-Earth asteroids ever to be discovered. Adonis was also the second known Apollo asteroid after 1862 Apollo, the group's namesake discovered four years earlier in 1932. After the initial discovery of Adonis, which happened during a close approach with Earth in 1936, the asteroid was observed for two months, before it became a lost asteroid, as not enough observations could be made to calculate a sufficiently accurate orbit. It took 41 years until it was finally rediscovered by the American astronomer Charles Kowal in 1977.
The asteroid orbits the Sun at a distance of 0.4–3.3 AU once every 2 years and 7 months (937 days). Its orbit has an eccentricity of 0.76 and an inclination of 1° with respect to the ecliptic. It is a potentially hazardous asteroid 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 0.0117 AU (1,750,000 km). The asteroid's orbit is well-determined for the next several hundred years. It also makes close approaches to Venus and Mars and comes within 30 Gm of the Earth six times in the 21st century, the nearest being 0.03569 AU (5,339,000 km) on 7 February 2036.
The minor planet is named from Greek mythology after the handsome, ever-youthful vegetation god Adonis, with whom the goddess Aphrodite fell in love. Persephone was also taken by Adonis' beauty and refused to give him back to Aphrodite. The dispute between the two goddesses was settled by Zeus: Adonis was to spend one-third of every year with each goddess and the last third wherever he chose. He was killed by a boar sent by Artemis. The minor planets 105 Artemis, 399 Persephone, 1388 Aphrodite and 5731 Zeus were named for these Greek gods. Naming citation was published before November 1977 (M.P.C. 4548).