Dynamics of Rotationally Fissioned Asteroids

Details Dynamics of Rotationally Fissioned Asteroids Dynamics of Rotationally Fissioned Asteroids

Oct 2010

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010dps....42.6307j&link_type=abstract

American Astronomical Society, DPS meeting #42, #63.07; Bulletin of the American Astronomical Society, Vol. 42, p.1093

Physics

Geophysics

Scientific paper

We present a model for near-Earth asteroid (NEA) rotational fission that results in the evolution of all observed types of NEA systems: synchronous binaries, asteroid pairs, doubly synchronous binaries, high-e binaries, ternary systems, and contact binaries. The model consists of "rubble pile” asteroid geophysics, the YORP and binary YORP effects, and mutual gravitational interactions. An NEA can be modeled as a ``rubble pile"--a collection of gravitationally bound boulders with a distribution of size scales and very little tensile strength between them. The YORP effect torques a "rubble pile” asteroid until the asteroid reaches its disruption spin limit, and then two collections of boulders will enter into orbit about each other determined by the largest distance between mass centers. This binary system dynamically evolves under the effects of non-spherical gravitational potentials, solar gravitational perturbations, and mutual body tides. The coupling between the spin states and orbit state chaotically drives the system into the observed asteroid classes with mass ratio, q, distinguishing two evolutionary tracks. High mass ratio systems, q>0.2, evolve tidally into doubly synchronous binaries and then continued to be evolved by BYORP. Low mass ratio systems, q<0.2, will disrupt on a timescale of 1 yr creating asteroid pairs unless another process interdicts. Before escape the secondary will often be spun up via gravitational torques until it too may fission, creating a chaotic ternary system. We call this new process secondary fission. The resulting triple system may eject one body or, more often, send one into a slow speed impact with the primary. These processes tend to stabilize the initially chaotic binaries to create synchronous binaries. These results emphasize the importance of the initial component size distribution and configuration within the parent body.
This work is supported by NASA's PGG and OPR programs through grants: NNX08AL51G and NNX09AU23G.

Affiliated with

Also associated with

No associations

Rating

Dynamics of Rotationally Fissioned Asteroids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Dynamics of Rotationally Fissioned Asteroids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamics of Rotationally Fissioned Asteroids will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1230499