How about the gravitational focus? IIRC, it is about 550 AU out,
a sphere (mumble, mumble, carry the 2...) about 10^28 square meters.
With a 1 mg sensor package at each square meter, it would mass about as
much as one of the terrestrial planets. No aluminum needed, and 100
times the light gathering. Omnidirectional, too.
On Sun, 18 Feb 2001, Robert J. Bradbury wrote:
> Well, if we assume that we dedicate all of the aluminium in
> the solar system (~6.6x10^23 kg) to reflective collecting
> area 600 nm thick (the minimum according to experts at the
> Univ. of Arizona Mirror Lab), that gives you 4.1x10^26 m^2
> of collecting area. That equates to a disc with a diameter
> of ~150 AU (*way* outside Pluto's orbit) or a sphere (looking in
> all directions) that has a radii of 38 AU (roughly Pluto's orbit).
> In practical terms, this translates into 43 trillion telescopes
> the diameter of the moon.
> So, even if you had a million years to channel surf, you
> you only get about a 0.7 sec/channel to make up your mind
> whether or not it is worth watching...
> So many channels, so little time.
This archive was generated by hypermail 2b30 : Mon May 28 2001 - 09:56:45 MDT