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From: karn@thumper.bellcore.com (Phil R. Karn)
Newsgroups: sci.space.shuttle,sci.space
Subject: Re: Moon or Mars? Editorial in _Air & Space Smithsonian_
Message-ID: <1033@thumper.bellcore.com>
Date: 7 Apr 88 07:56:58 GMT
References: <47032@sun.uucp> <1290@hubcap.UUCP> <4076@whuts.UUCP> <1384@silver.bacs.indiana.edu>
Organization: Bell Communications Research, Inc
Lines: 14
Summary: sunlight percentages in orbit

> 	If you would think about it, a satellite could be in sunlight
> almost all the time(e.g.) a polar orbit.

Not really. To do what you want for an appreciable length of time, you
want a "sun synchronous" orbit phased over the terminator. This is
actually pretty easy to do with the earth (almost every launch from
Vandenburg goes into sun-synchronous orbit, though usually not over the
terminator).  But a sun-synchronous lunar orbit is much more difficult
because of the moon's far more irregular gravity field, and because of the
earth's proportionately larger perturbations.

I was thinking of a lunar equatorial orbit mainly because it's much cheaper
to get there.

Phil