Astronomy Picture of the Day
Discover the cosmos!
Each day a different image or photograph of our fascinating universe is
featured, along with a brief explanation written by a professional
A Radar Image of Planet Earth
JPL Imaging Radar Program
This image of
Mt. Rainier, Washington USA, planet Earth,
was produced by the
Spaceborne Radar Laboratory
which flew on the
Space Shuttle Endeavour in 1994.
Radar, short for RAdio Detection And Ranging, is a technique which
coordinates the operation of a radio transmitter and receiver to
measure the direction, strength, and timing of radio echos from the surface
of distant objects. An actual image of an object can be constructed by
recording and analyzing many echos.
One advantage of using radar imaging in planetary studies
is that images can be made regardless of cloud cover
or lighting conditions.
During the early 90s, NASA's
was able to use radar imaging to produce similar high resolution maps of
the surface of Venus.
For more information about the picture
Tomorrow's picture: A World Explorer
| About APOD
Authors & editors:
NASA Technical Rep.:
Specific rights apply.
A service of:
Michigan Tech. U.