SETI public: Fw: Relativistic communications

• Previous message: LARRY KLAES: "SETI public: The 2004 Astrobiology Conference"

----- Original Message -----
From: Robert J. Bradbury<mailto:bradbury_at_aeiveos.com>
To: dale.hooper_at_comcast.net<mailto:dale.hooper_at_comcast.net>
Cc: public_at_setileague.org<mailto:public_at_setileague.org> ; Larry Klaes<mailto:ljk4_at_msn.com>
Sent: Wednesday, April 14, 2004 1:38 PM
Subject: Re: Relativistic communications

I'm reasonably familiar with much of the SETI literature and
to the best of my knowledge no analysis has been done of
gamma ray bursts for "structure" or modulation.

One of the problems with this is that both the production
and detection of messages in the gamma ray to X-ray frequency
range is very difficult. I do not believe that even
relativistic probe speeds would shift the frequency enough
to get you into reasonable frequency ranges.

The second problem has to do with the idea of relativistic
probes in the first place. At those speeds if you encounter
a piece of space dust or components of a solar wind one is
going to produce a lot of energy which will cause probe mass
erosion. There is most probably a galactic speed limit
which it is likely should not be exceeded. The Project Daedalus
probe which was going relatively slow dealt with this by having
to include an ablative shield for its encounters with dust/ions.
I believe that our knowledge of the universe has expanded to
recognize that this may be much more of a problem than was
thought when that work was done (circa 1978).

Robert

• Previous message: LARRY KLAES: "SETI public: The 2004 Astrobiology Conference"

This archive was generated by hypermail 2.1.6 : Wed Apr 14 2004 - 11:15:22 PDT