[amsat-bb] Re: Asteroid echos on 2380 MHz

["Edward R. Cole" <al7eb@xxxxxxxxxxxxx>]

ARRL article:
http://www.arrl.org/news/stories/2002/08/15/3/?nc=1

Link from the ARRL article:
http://neo.jpl.nasa.gov/cgi-bin/db?name=2002+NY40+&group=all&search=Search

There is a box listing orbital elements that you can manually enter into a
tracking program.

The asteroid is purportedly about 1/2 mile in diameter and passing at a
distance of 300,000 miles (just beyond the orbit of the moon).  So how
strong an echo will this tiny rock produce compared to a moonbounce signal
(off a much bigger rock!)?  Of course Arecibo will be running a signal 9000
times as powerful as is used on 2304 MHz eme (avg 100w), and with 40 dB
more antenna gain!  That's about 80 dB stronger!  the moon is about a
quarter the size of the earth (guessing 2000 miles diameter) so that is
(very) roughly (Drock)^2/ (Dmoon)^2 = 1/16,000,000 weaker reflection!

So whatdya say?  Is this possible?

Ed, AL7EB

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