(887) Alinda

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(887) Alinda
Properties of the orbit ( animation )
Orbit type Near-Earth asteroid, Cupid-type
Major semi-axis 2.4842  AU
eccentricity 0.5647
Perihelion - aphelion 1.0815 AU - 3.8870 AU
Inclination of the orbit plane 9.3329 °
Sidereal period 3.92 years
Mean orbital velocity 18.89 km / s
Physical Properties
Medium diameter 4.2 km
Dimensions ? Template: Infobox asteroid / maintenance / masskg
Albedo 0.31
Medium density ? g / cm³
Rotation period 73.97 h
Absolute brightness 13.76 mag
Spectral class S type
Explorer Max Wolf
Date of discovery January 3, 1918
Another name 1918 DB
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items.

(887) Alinda is a planetoid belonging to the group of Cupid asteroids .
Alinda was discovered on January 3rd, 1918 by the German astronomer Max Wolf . The asteroid is named either after the city of Alinda in Asia Minor or after a figure from the mythology of the Australian Aborigines ( man in the moon ).

Alinda moves between 1.0815  AU ( perihelion ) and 3.8870 AU ( aphelion ) in 3.92 years on a very eccentric (e = 0.5647) orbit around the sun . This is inclined by 9.3329 ° to the ecliptic .

Alinda has a diameter of 4.2 km and rotates on its own axis in about 73 hours and 58 seconds. The albedo is 0.31. Alinda achieves a brightness of 9.8 mag at a maximum possible approach to earth of 0.1037 AU .

Alinda group

In addition to belonging to the Cupid asteroids, Alinda has some special properties that make her the namesake of her own group of objects. This group moves in a 3: 1 orbital resonance to Jupiter and in a 1: 4 resonance to Earth, i.e. That is, they orbit the sun three times during one orbit of Jupiter and once within four earth years. Members have half-axes of about 2.5 AU. The orbits of these asteroids are disturbed by the resonance to Jupiter, which leads to the fact that the area there is cleared of asteroids (there is one of the Kirkwood gaps of the main belt ). As a result, the eccentricities of these objects are constantly increased until the resonance is resolved upon approaching one of the inner planets. Some Alinda asteroids have their perihelion near or within the Earth's orbit. Another representative of this group is the asteroid (4179) Toutatis , which, due to its 1: 4 resonance with the earth's orbit, regularly approaches our home planet about every four years.

See also