NOAO >   Observing Info >   Approved Programs >   2014A-0424

Small NOAO Logo

Proposal Information for 2014A-0424


PI: Beatrice Mueller, Planetary Science Institute, mueller@psi.edu
Address: 1700 E. Ft. Lowell, #106, Tucson, Arizona 85719, United States

CoI: Nalin Samarasinha, Planetary Science Institute
CoI: Jean-Baptiste Kikwaya Eluo, Vatican Observatory

Title: Tying Changes in Cometary Rotation to Nuclear Activity: A Substantial Increase in the Database

Abstract: In a recent paper, Samarasinha and Mueller (2013) introduced a parameter, X, to describe the changes in the rotational period of a comet in terms of the rotational period itself, the nuclear radius, and the orbital characteristics. They showed that X should be a constant if the bulk densities and shapes of the nuclei are nearly identical and the activity patterns are similar for all comets. For four nuclei (2P/Encke, 9P/Tempel 1, 10P/Tempel 2, and 103P/Hartley 2) for which rotational changes are well documented, despite the nearly factor 30 variation observed among the effective active fractions of these comets, X is constant to within a factor two (see Table 1). If that is the case for all comets, X can be used as a predictor for rotational changes. We propose to observe comets 46P/Wirtanen, 19P/Borrelly (and P/2004 R1 (McNaught) if it is sufficiently bright) to add two or three comets to the sample listed above and to derive accurate rotation periods, and eventually to determine the change in the respective rotation periods to confirm the near-constancy of the parameter X.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2014A-0424

noaoprop-help@noao.edu

Small NOAO Logo