Astronomy and Astrophysics – Astronomy
Scientific paper
Sep 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009dps....41.5605s&link_type=abstract
American Astronomical Society, DPS meeting #41, #56.05
Astronomy and Astrophysics
Astronomy
Scientific paper
The torques on small asteroids produced by radiation recoil (the YORP effect) are shown to be extremely sensitive to small-scale surface topography. A numerical approach is used to calculate the expected relative errors in the spin and obliquity components of the predicted YORP torque caused by observationally unresolved Gaussian surface fluctuations, craters, and boulders. Gaussian topography produces errors of order 100% if observations cannot constrain the surface to a spherical harmonic order l > 10; constraining the surface to l > 20 can keep expected errors under 10%. However, craters and boulders have larger influence. A single moderately-sized crater placed at random locations alters the torque components by several tens of percent. Objects that are identical but for the location of a single large crater can differ by factors of several in torque, while being photometrically indistinguishable. Randomly placed boulders produce torque errors roughly 3 times larger than do craters of the same diameter. A single large boulder, shifted by twice its own diameter, can change the magnitude of the torque by factors of several, as well as its sign. The total expected error produced by multiple craters is contributed by the handful of largest craters; but large and small boulders contribute comparably to the total boulder-induced error. A YORP prediction derived from groundbased data is probably in error by of order 100% due to unresolved topography. Furthermore, surface changes caused by slow spin-up or spin-down may cause objects with rotation periods between roughly 2 and 10 hours to random-walk up and down in spin rate before fissioning or loss of surface objects occurs. Similar behavior may be expected at higher rotation rates close to the limits for tensile-strength dominated objects.
No associations
LandOfFree
Topographic Indeterminacy of the YORP Effect 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 Topographic Indeterminacy of the YORP Effect, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Topographic Indeterminacy of the YORP Effect will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1333820