Pallas family

From Wikipedia, the free encyclopedia

The Pallas family of asteroids is a grouping of B-type asteroids at very high inclinations in the intermediate main belt (Cellino et al (2002)).

The namesake is 2 Pallas, an extremely large asteroid with a mean diameter of about 530 km. The remaining bodies are far smaller (the largest being 5222 Ioffe with an estimated diameter of 22 km), which indicates that this is probably a so-called cratering family composed of ejecta from impacts onto the parent body 2 Pallas.

Location and structure of the Pallas family.
Location and structure of the Pallas family.

From the diagram, their proper orbital elements lie in the approximate ranges

ap ep ip
min 2.71 AU 0.25 32°
max 2.79 AU 0.31 34°

At the present epoch, the range of osculating orbital elements of the members (by comparison to the MPCORB database [1]) is about

a e i
min 2.71 AU 0.13 30°
max 2.79 AU 0.37 38°

The family appears to be genuinely derived from impacts onto Pallas due to the preponderance of the otherwise rare B spectral type among its members.

The grouping was first noted by Kiyotsugu Hirayama in 1928, and later by Brouwer (1951), Kozai (1979), and Lemaitre&Morbidelli (1994).

[edit] References

Languages