High Resolution Surface Brightness Profiles of Near-Earth Asteroids
نویسندگان
چکیده
We present a new method to search for and est imate mass loss in near-Earth asteroids (NEAs) using high resolution surface photometry. The method was applied to 11 NEAs observed with a charge-coupled device (CCD) at the University of Hawaii 2.2-m telescope. The method yields limiting mass loss rates M -< 0.1 kg sec-1, 1-2 orders of magnitude smaller than the typical rates of weakly active comets. However, these mass loss rate upper limits imply fractional active areas in NEAs that are comparable to cometary fractional active areas. Because of the small sizes of the NEAs, the mass loss rates produced by these fractional active areas are below the detection limit of current techniques; thus there may exist low-level cometary activity amongst the NEAs which goes unnoticed. ~ 1992 Academic Press, Inc.
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