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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Radar Image of Asteroid 1989 PB
Science (New York, N.Y.)
|June 22, 1990
Summary
Radar imaging revealed near-Earth asteroid 1989 PB is a contact-binary object. This suggests the asteroid
Area of Science:
- Planetary Science
- Astronomy
- Radar Astronomy
Background:
- Near-Earth asteroids (NEAs) are remnants from the early solar system.
- Understanding asteroid composition and structure is crucial for planetary defense.
Purpose of the Study:
- To characterize the physical structure of NEA 1989 PB.
- To investigate the formation mechanism of contact-binary asteroids.
Main Methods:
- Delay-Doppler radar imaging.
- Analysis of radar echo data.
Main Results:
- NEA 1989 PB exhibits a contact-binary shape, composed of two distinct lobes.
- The lobes appear to be in physical contact, suggesting a recent merger.
Conclusions:
- The contact-binary structure of 1989 PB likely resulted from a low-velocity collision between two previously separate bodies.
- This finding provides insights into the collisional evolution of small solar system bodies.
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