Pallas family

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The Pallas or Palladian family of asteroids is a grouping of B-type asteroids at very high inclinations in the intermediate asteroid belt (Cellino et al. (2002)). It was first noted by Kiyotsugu Hirayama in 1928.[citation needed]

The namesake of the family is 2 Pallas, an extremely large asteroid with a mean diameter of about 512 km.[1] The remaining bodies are far smaller; the largest is 5222 Ioffe with an estimated diameter of 22 km. This, along with the preponderance of the otherwise rare B spectral type among its members, indicates that this is likely a cratering family composed of ejecta from impacts on Pallas. Another suspected Palladian is 3200 Phaethon, the parent body of the Geminid meteor shower.[2]

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°