HR: 0800h
AN: P41A-0221    [Abstracts]
TI: The NEAT database photometry and constraints on the rotation of 5535 AnneFrank.
AU: * Bauer, J M
EM: bauer@scn.jpl.nasa.gov
AF: Jet Propulsion Laboratory California Institute of Technology, 4800 Oak Grove Drive, MS183-501, Pasadena, CA 91024, United States
AU: Schmidt, B E
EM: britneys@ucla.edu
AF: UCLA-IGPP, 595 Charles Young Drive East, 3806 Geology building, Los Angeles, CA 90095-1567, United States
AU: Lawrence, K J
EM: kjl@mipl.jpl.nasa.gov
AF: Jet Propulsion Laboratory California Institute of Technology, 4800 Oak Grove Drive, MS183-501, Pasadena, CA 91024, United States
AU: Buratti, B J
EM: Bonnie.Buratti@jpl.nasa.gov
AF: Jet Propulsion Laboratory California Institute of Technology, 4800 Oak Grove Drive, MS183-501, Pasadena, CA 91024, United States
AU: Eckel, J
EM: jeckel@andrew.cmu.edu
AF: Jet Propulsion Laboratory California Institute of Technology, 4800 Oak Grove Drive, MS183-501, Pasadena, CA 91024, United States
AU: Petersen, P
EM: pfp8@aol.com
AF: Jet Propulsion Laboratory California Institute of Technology, 4800 Oak Grove Drive, MS183-501, Pasadena, CA 91024, United States
AU: Hillier, J K
EM: jhillier@ghc.edu
AF: Department of Mathematics and Science Grays Harbor College, 1620 Edward Smith Drive, Aberdeen, WA 98520, United States
AB: In November of 2002, the main belt asteroid 5535 Annefrank was observed over a 26-minute window with the Stardust spacecraft. During this time, the first spacecraft images of this S-class asteroid were taken over ~40% of the surface at a resolution of 185-300 m/pixel (Duxbury et al. 2004). Stardust collected 72 images at varying phase angles, producing a phase curve out to 134 degrees and a geometric albedo of 0.24. Annefrank's orientation, shape and size were constrained by the encounter's imaging data, revealing a minimum triaxial ellipsoid size of 6.6 x 5.0 x 3.4 km, and irregular topography, including a protrusion along the end of its longest axis. Owing to the brevity of the observing window no constraints on the rotational period or spin axis orientation were made by the encounter, and Annefrank is assumed to be a slow-rotator. Thus, we began a campaign to observe Annefrank in May of 2005 through December of 2006 using the 0.6 meter telescope at Table Mountain Observatory, run by Caltech's/Jet Propulsion Laboratory (JPL). A total of 14 nights of observation yielded a light curve with possible rotational periods of 0.48, 0.63, and 0.95 days, so that further constrains were required to determine its rotation and spin axis orientation. The Near-Earth Asteroid Tracking (NEAT) project at JPL has systematically observed the sky for more than a decade. While the main objective of NEAT is the discovery of near-earth objects (NEOs), the NEAT database provides multiple observations over varying time scales (hours, days, months and years). As a result, the NEAT database provides a history of behavior over a time span of more than ten years and can serve as a powerful tool to analyze the time-dependent nature of solar system bodies. We use the NEAT database here to conduct a photometric study of 5535 Annefrank to better constrain the period and derive an orientation of the spin axis. The data have also been used to conduct photometry and derive phase curves of bright outer solar system objects, and we present a subset of these results as well. This research was funded in part by NASA through the Discovery Data Analysis Program. This work was performed in part at the Jet Propulsion Laboratory operated by the California Institute of Technology under contract with NASA.
DE: 5464 Remote sensing
DE: 6035 Orbital and rotational dynamics
DE: 6055 Surfaces
DE: 6205 Asteroids
DE: 6211 Centaurs
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting