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Proposal Identication No.: R1792 Date Received: 2003-Apr-08 17:12:36
Technical Page
Proposal Type: Urgent
General Category: Planetary Radar
Observation Category: Solar System
Total Time Requested: 9 Hours
Proposal Title: Radar Observations of 2003 GF21
ABSTRACT:
The near-Earth object, 2003 GF21, is observable with the Arecibo planetary radar on April 12-14. This object is
expected to be about 150m in diameter, and is 0.04 AU from the Earth. The expected signal-to-noise ratio is over
50, which will yield images of good quality, approximately 10x5 pixels in size. The number of near-Earth asteroids
observed is still very small, given the large variety of sizes, shapes and rotation properties that have been seen.
Radar observations can give insight into the internal structure by showing the shape and rotation properties, for
example small, round structures must be strenghtless rubble piles, while rapidly rotating bars must be intact shards
with little or no regolith. Binary systems allow the determination of densities, and internal porosity. Continuing to
take advantage of targets of opportunity will help us to understand the nature of the near-Earth asteroid
population.
Name Institution E-mail Phone Student
Ellen S Howell Arecibo Observatory ehowell@naic.edu 787-878-2612
x282
no
Service Observing Request Remot e Observing Request
X None X No
All of the observing run. Maybe
Part of the observing run. Yes
Queue Observing
Instrument Setup
S-Band radar S-band receiver
Atmospheric Observation Instruments:
Special Equipment or setup: none
RFI Considerations
1

Frequency Ranges Planned
2