Mathematics – Logic
Scientific paper
Jan 1999
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1999lpico.988...21o&link_type=abstract
Space Resources Utilization Roundtable, p. 21
Mathematics
Logic
Radar Detection, Radar Measurement, Radar Scattering, Radar Tracking, Reconnaissance, Asteroids, Extraterrestrial Resources, Flyby Missions, Rendezvous Spacecraft, Telescopes, Cost Reduction
Scientific paper
Groundbased radar observations of NEAs can help identify space resources with commercial potential and can dramatically reduce the cost and risk of the initial spacecraft missions to those objects. The near-Earth asteroid (NEA) population is thought to contain approximately 1500 objects as large as a kilometer, approximately 300,000 as large as 100 meters, and more than 100,000,000 as large as 10 meters. More than 10% of the NEAs are more accessible in terms of mission delta-V (i.e., fuel required) than the Moon, Mars, or the moons of Mars. Fewer than 1000 NEAs have been found, but the discovery rate is increasing rapidly. Once an asteroid is discovered (necessarily by wide-field optical telescopes), radar can provide otherwise unavailable information about its size, shape, spin state, and surface properties if it approaches within the range of the Goldstone (California) or Arecibo (Puerto Rico) radar telescopes. Asteroids generally appear as unresolved points through groundbased optical telescopes, but radar measurements of the distribution of echo power in time delay (range) and Doppler frequency (radial velocity) can yield images with resolution as fine as a decameter. Image sequences that furnish adequate orientational coverage can be inverted to construct geologically detailed 3-D models, to define the rotation state precisely, and to constrain the object's internal density distribution. Estimates of radar scattering properties characterize the surface's cm-to-m-scale roughness as well as its bulk density, which for asteroids depends primarily on porosity and metal concentration. A useful spin-off of radar detection is orbit refinement that simplifies navigation of flyby and rendezvous spacecraft.
No associations
LandOfFree
Radar Reconnaissance of Near-Earth Asteroids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Radar Reconnaissance of Near-Earth Asteroids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radar Reconnaissance of Near-Earth Asteroids will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1611662