Figure 7
Arecibo Observatory
The Arecibo Observatory, in Puerto Rico, is the premier radio
telescope instrument used in the Earth-based study of the planets and small
bodies in the solar system. It is capable of beaming a powerful signal into
space ancj receiving the radio waves reflected from the source. The telescope
has been used to map the surface characteristic.s of the Moon, Venus, and Mars,
and recently has started to provide data on the physical properties of near-Earth
asteroids. The radio wave reflection properties are affected strongly by the
surface roughness and by the granularity of surface materials, and to a more
limited extent by the composition of the asteroids.