Automated CCD Scanning for Near Earth Asteroids

Abstract

The Spacewatch group at the University of Arizona's Lunar and Planetary Laboratory was probably the first (1984) to implement CCD-scanning in a major astronomical program. In the past three years, using a Tektronix 2048 × 2048 CCD, the program has discovered ∼ 45% of the new Earth approaching asteroids, measured astrometric positions for over 50,000 main belt asteroids, discovered two of the three known Centaurs, and found evidence for an unheralded population of small (∼ 10-m) objects in the inner solar system. This success is due to the automated Moving Object Detection Program (MODP) which searches successive scans over the same region for objects showing consistent motion. While visual examination of photographic plates may have a higher efficiency, an automated routine for detecting moving objects does not tire and is repeatable. Our recent work quantifies the efficiency of MODP as a function of the asteroid's magnitude, rate of motion, and orbital parameters. Other work suggests that the observational detection of faint, trailed, Fast Moving Objects may be improved by incorporating linear darkfield subtraction and flatfielding during scans.