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Path: utzoo!utcsri!hogg
From: hogg@utcsri.UUCP (John Hogg)
Newsgroups: net.space
Subject: Re: Asynchronous orbital skyhooks (those two masses...)
Message-ID: <1893@utcsri.UUCP>
Date: Mon, 6-Jan-86 09:41:55 EST
Article-I.D.: utcsri.1893
Posted: Mon Jan  6 09:41:55 1986
Date-Received: Mon, 6-Jan-86 09:44:30 EST
References: <8512312026.AA15784@s1-b.arpa> <70@dg_rtp.UUCP>
Reply-To: hogg@utcsri.UUCP (John Hogg)
Organization: CSRI, University of Toronto
Lines: 33
Summary: 

In article <70@dg_rtp.UUCP> throopw@dg_rtp.UUCP (Wayne Throop) writes:
>Question:  since synchronous orbital skyhooks are considered feasible
>for Mars and the Moon, why isn't more attention given to asynchronous
>orbital skyhooks for providing various delta-vs in orbital injection
>scenarios near Earth?  Is the idea intrinsically non-feasible, or what?

I like it, you like it, and most readers of this group will too, but...
if things go wrong, skyhooks fall DOWN.  Remember the Skylab hysteria?  If
a skyhook breaks at almost any point in its rotation, one part goes up, and
the other hits the atmosphere FAST.  Kevlar cable will burn up in short
order.  Anything larger, such as payload, stands a good chance of reaching
the ground.  Again, WE all know how dangerous this is in the context of our
daily existence, but there could be real political problems in putting
something "large" up there with the tight safety margins required to make
this feasible.  Californian lawyers could have a field day out of it even
if nothing happened.

By the way, Kevlar makes fast sails, but
	1) How do you protect it from sunrot without an excessive weight
	   penalty?
	2) What about LEO free oxygen?
	3) How well does it behave at the temperature extremes to be
	   expected in space?
These aren't reasons why it "can't be done"; I'm just wondering whether
anybody has made the appropriate calculations.
-- 

John Hogg
Computer Systems Research Institute, UofT
...utzoo!utcsri!hogg

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