A collisional family of icy objA collisional family of icy objects in the Kuiper beltects in the Kuiper belt

Michael E. Brown, Kristina M. Barkume, DMichael E. Brown, Kristina M. Barkume, Darin Ragozzine & Emily L. Scallerarin Ragozzine & Emily L. Scaller

Nature 446, 294Nature 446, 29415 March, 200715 March, 2007

2007.5.29 Soccer

This diagram was created by Piotr Deuar using data for 96944 minor planets, which was obtained from the AstDys site. Data was dated March 2005, calculation was by Z. Knezevic and A. Milani.

Using W. M. Keck Telescope, they Using W. M. Keck Telescope, they obtained 26 bright KBOs’ spectra in near obtained 26 bright KBOs’ spectra in near infrared range. They also got the spectra infrared range. They also got the spectra of other six KBOs from published data.of other six KBOs from published data.

2003 EL61

The change in reflectance per 100nm between 0.5 and 0.8 μm.

Using the SWIFT orbital integration Using the SWIFT orbital integration package, they integrate the orbits of each package, they integrate the orbits of each of the KBOs for a period of 50 Myr of the KBOs for a period of 50 Myr including only the gravitational influence of including only the gravitational influence of the sun and the four giant planets.the sun and the four giant planets.

Conclusion:

They report the discovery of a family of Kuiper belt objects with surface properties and orbits that are nearly identical to those of 2003EL61. This family appears to be fragments of the ejected ice mantle of 2003EL61.

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