Aucbvax.6317
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Fri Feb 26 03:35:40 1982
SPACE Digest V2 #116
>From OTA@S1-A Fri Feb 26 01:31:22 1982
SPACE Digest Volume 2 : Issue 116
Today's Topics:
Quasars
Wierd accelerators
flying short, stubby I-beams
Quasars
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Date: 25 Feb 1982 0716-PST
From: Paul Dietz <DIETZ AT USC-ECL>
Subject: Quasars
To: Reed.ES at PARC-MAXC
cc: space at MIT-MC
Gravitational redshift is ruled out because the redshift is so great.
A large cluster of stars (say) of sufficient density to get that redshfit
would be unstable to gravitational collapse.
If the quasars are local objects associated with our galaxy, calculations
indicate that the energy necessary to accelerate them to their observed
velocities is many, MANY solar masses, far too much to be believable.
And why don't we see them around other galaxies, blue-shifted?
Some evidence for the traditional view includes the fact that quasars
resemble less active radio galaxies in that they have radio lobes,
and the observation of a gravitational lens involving a quasar. This
last doesn't work unless the quasar is very far away.
-------
------------------------------
Date: 25 Feb 1982 09:40 PST
From: Stewart at PARC-MAXC
Subject: Wierd accelerators
To: Space@MIT-MC
cc: Stewart
Take the skyhook rope, tie a probe on the end, and whirl the affair around a
suitable asteroid. As the rope wraps around the asteroid, the probe will reach 0.5
c and then you let go.
At least as feasible as the bloater drive.
-Larry
PS Remind me to write up my wood burning TV receiver.
------------------------------
Date: Thursday, 25 February 1982 09:41-PST
From: KING at KESTREL
Subject: flying short, stubby I-beams
To: ota at s1-a
cc: King at KESTREL, space at mit-mc
I seem to remember that the strength required of an object of
a given design to resist a given acceleration is proportional to the
cube root of its mass. (All load-bearing members' cross sections are
proportional to the square of a linear dimension, and the the mass of
the object is proportional to the cube.)
If I remember correctly, the strength of structural steel is
approximately 1000 KPSI. If I wanted to send an I-beam to another
galaxy, the load on its base would have to be
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