Re: using a microsat as a potential high altitudeVHF reflector
I still think that a large unfolded and/or (partially?) inflatable structure of reflective material structured as resonant reflectors could be an interesting passive reflector of ham frequencies if it was placed on the Moon. It would be easier than a powered active repeater.
I know about moonbounce obviously and the laser system left behind by Apollo.
73 de andy G0SFJ
Has any Amateur been able to bounce a laser off the reflectors on the moon? I wonder what power of a laser is needed to make the round trip. Plain and using a telescope for both Transmit and receive. Hey a telescope is a parabolic dish made for those freqs.
I wonder what the DB gain of a 6" and 10" diameter scope, at the freq of the popular strong green lasers?
BE Careful though watch out for planes!
Joe WB9SBD ---- Idle-Tyme The Original Rolling Ball Clock http://www.idle-tyme.com
andy thomas wrote:
I still think that a large unfolded and/or (partially?) inflatable structure of reflective material structured as resonant reflectors could be an interesting passive reflector of ham frequencies if it was placed on the Moon. It would be easier than a powered active repeater.
I know about moonbounce obviously and the laser system left behind by Apollo.
73 de andy G0SFJ
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Or the reflectors on Castor or Pollux?
Idle-Tyme wrote:
Has any Amateur been able to bounce a laser off the reflectors on the moon?
That Spinning I don't think we would be able to see it or at least be able to communicate with like CW with it But i could be wrong? I'm not familiar with how stable the reflections are.
Joe WB9SBD ---- Idle-Tyme The Original Rolling Ball Clock http://www.idle-tyme.com
Nigel Gunn G8IFF/W8IFF wrote:
Or the reflectors on Castor or Pollux?
Idle-Tyme wrote:
Has any Amateur been able to bounce a laser off the reflectors on the moon?
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----- Original Message ----- From: "andy thomas" andythomasmail@yahoo.co.uk To: "amsat" amsat-bb@amsat.org Sent: Thursday, October 29, 2009 11:04 AM Subject: [amsat-bb] Re: using a microsat as a potential high altitudeVHFreflector
I still think that a large unfolded and/or (partially?) inflatable
structure of reflective material structured as resonant reflectors could be an interesting passive reflector of ham frequencies if it was placed on the Moon. It would be easier than a powered active repeater.
I know about moonbounce obviously and the laser system left behind by
Apollo.
73 de andy G0SFJ
Hi Andy, G0SFJ
I have many doubts about your idea because the surface of the moon as seen as a radar target is large as 9.45 x 10^12 square meters and is isotropically backscatterig only the 7% of the power of radio waves incident over it for the frequencies ranging from 144 to 1296 MHz
Actually EME is made under the above conditions like the moon was large only 9.45 x 10^12 x 0.07 = 6.615 x 10^11 square meters but made with a material totally reflecting isotropically the 100 % of power incident over it.
If now we assume that hypothetically you can put over the moon a passive inflatable structure of reflective material with 100 % of reflectibility then to made EME with the same actual moon-bounce results the above inflatable surface would be made large as 6.615 x 10^11 square meters i.e. it's impossible.
If such thing would be possible the diameter of the above inflatable structure if placed at the distance earth-moon it would be seen in the sky sottending an angle of 0.14 degrees but actually the moon is sottending 0.5 degrees so that imagine how big would be the above inflatable reflector on the moon and figure out if it would be easier to made instead to use a powered active repeater.
73" de
i8CVS Domenico
participants (4)
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andy thomas -
i8cvs -
Idle-Tyme -
Nigel Gunn G8IFF/W8IFF