How do collisions affect the evolution of objects in the Oort cloud?

[mersecske]

How frequent are collisions in the ooort cloud?
Are there any good reference in the literature about this topic?

 

[Nik_2213]

IIRC, the Oort Cloud is still beyond our telescopes' sensitivity, although the recent infrared survey should find some denizens...

( There's even some argument about the Oort Cloud's existence: IIRC, it is inferred from the 'near hyperbolic' orbits of long-period comets... )

I remember reading of a 'dim' comet which suddenly flared. A collision with a small asteroid could account for its unusual pattern of spreading debris. However, some months later, another 'dim' comet flared likewise. The chance of two such collisions was so small that opinion swung to a major out-gassing event for both...

Uh, stuff does collide: After the Shoemaker-Levy9 mega-event, several amateur astronomers began watching Jupiter more closely. IIRC, they've since spotted the flash and/or dark patch of two small impactors. However, Jupiter's gravity will sweep a lot more volume than a trans-Neptunian Plutoid or dwarf planet...

 

[Ophiolite]

The very low density of material in the Oort cloud minimises the opportunity for collisions. However, Stern comments that impacts "cause extensive surface evolution to develop on comets in the cloud, if the number of small objects orbiting in the cloud is in accordance with “standard” power-law populations." (Stern, S.A. Collisions in the Oort Cloud. Icarus 73, 499–507 (1988).)

Stern has also written http://www.boulder.swri.edu/AR2003/Nature_comets.pdf" , from 2003.

http://arxiv.org/ftp/astro-ph/papers/0609/0609807.pdf" by Charnox and Morbidelli examines the collisional history during the formation of the Oort cloud.