Faint moving object detection, and the Low Signal-to-Noise recovery of Main Belt comet P/2008 R1 Garradd

Abstract

We describe the recovery of faint Main Belt comet P/2008 R1 Garradd using several telescopes, culminating in a successful low $S/N$ recovery with the Gemini North telescope with GMOS. This recovery was a time-critical effort for a mission proposal, and had to be performed in a crowded field. We describe techniques and software tools for eliminating systematic noise artifacts and stellar residuals, bringing the final detection image statistics close to the Gaussian ideal for a median image stack, and achieving a detection sensitivity close to this theoretical optimum. The magnitude of $R_c$=26.1$\pm$0.2 with an assumed geometric albedo of 0.05 corresponds to a radius of 0.3 km. For ice to have survived in this object over the age of the solar system, it implies that the object is a more recent collisional fragment. We discuss the implications of the unexpectedly faint magnitude and nuclear size of P/2008 R1 on the survival of ice inside very small bodies.

arXiv comment15 pages, 4 figures; accepted for publications in PASP

References in corpus (5)

• The Active Asteroids
• Analytical protostellar disk models 1: the effect of internal dissipation and surface irradiation on the structure of disks and the location of the snow line around Sun-like stars
• Main-Belt Comet P/2008 R1 (Garradd)
• Physical Properties of Main-Belt Comet P/2005 U1 (Read)
• Calibration of photometry from the Gemini Multi-Object Spectrograph on Gemini North

Cited by in corpus (2)

• SAFARI: Searching Asteroids For Activity Revealing Indicators
• The location of Asteroidal Belt Comets (ABCs), in a comets' evolutionary diagram: The Lazarus Comets