Radiometry of near-earth asteroids

Area of Science:

• Astronomy and astrophysics
• Planetary science
• Infrared astronomy

Background:

• Near-Earth asteroids (NEAs) are crucial for understanding solar system evolution and potential impact hazards.
• Characterizing NEA surface properties, such as albedo and thermal inertia, provides clues to their composition and origin.
• Previous studies have utilized various observational techniques to classify NEAs, but detailed thermal property analysis remains ongoing.

Purpose of the Study:

• To present 10-micrometer infrared photometry data for a sample of 22 Aten, Apollo, and Amor asteroids.
• To derive radiometric albedos and diameters for these asteroids using thermal modeling.
• To investigate the surface thermal inertia and infer surface properties (e.g., bare rock, coarse regolith) of the studied NEAs.

Main Methods:

• Acquisition of 10-micrometer infrared photometric data for 22 NEAs.
• Application of thermal modeling techniques to analyze the infrared data.
• Calculation of radiometric albedos and diameters based on the thermal models.

Main Results:

• Photometric data and derived physical parameters (albedo, diameter) for 22 NEAs.
• Identification of several asteroids with high thermal inertia, indicative of exposed rock or coarse regolith.
• Classification of Apollo asteroid 3103 (1982 BB) as class E.
• Confirmation of Jupiter-crossing Amor asteroid 3552 (1983 SA) as class D.

Conclusions:

• The study provides valuable infrared observational data for a sample of NEAs.
• The findings suggest a diversity of surface properties among NEAs, with some exhibiting characteristics of bare rock.
• Low albedos remain uncommon among the studied near-Earth asteroids, consistent with broader trends.