[net.physics] Earth - Moon simulator

smb@ulysses.UUCP (11/13/83)

(sorry to post this; an attempt to reply by mail failed.)

For calculating Earth-moon distances, see "Practical Astronomy with your
Calculator", by Peter Duffett-Smith.  It's published by Cambridge University
Press in both hardcover and soft- cover.  It seems to have what you want,
and much more besides.

		--Steve Bellovin
		Bell Labs
		ulysses!smb@Berkeley

Craig.Everhart%CMU-CS-A@sri-unix.UUCP (11/14/83)

I've got a program that does a crude job of what you ask for--its use is to
figure out the phase and orientation of the moon (how it's tilted if you were
to face toward it) so it can draw a picture of it on your terminal as you
log out.  My astronomy is much simplified, but it seems to simulate reality
pretty well.  Let me know if you can retrieve a copy and I'll pin down where
it is, or I'll mail you a copy of the program if you can't do it.

Before it can figure out what orientation the moon will seem to be at, it
goes through a stage where it figures the azimuth and elevation of the moon's
center.  It just does it for a compiled-in latitude and it assumes that local
time is solar time, but it should be easy to get it to do what you want.

Any astronomical improvements (say, the prediction of eclipses) would be
most welcome.

		Craig Everhart

stan@clyde.UUCP (Stan King) (11/16/83)

     Does anyone know of the existence of an Earth - Moon simulator that
would, if given a longitude-latitude point on the earth and a time, tell
me the azimuth and elevation readings to the center of the moon from
that point?
     Thanks,
     Daniel C Weller
=-=-=
Forgive me for posting this, but I seriously doubt if mailing to
sri-unix!"DanielCWeller"@HIS-PHOENIX-MULTICS.ARPA would work.

Anyway, Proceedings of IEEE recently had a special issue on global
navigation systems.  One article spoke of a publication called "Almanac
for Computers," which gave ephemerides in series form for easy computation
by calculators and what not.  They also discussed the possible errors
in that and other computational models of ephemerides.

		Stan King			phone: 201-386-7433
		Bell Labs, Whippany, NJ		Cornet:  8+232-7433
		room 2A-111			uucp:	 clyde!stan

james@umcp-cs.UUCP (11/17/83)

The Naval Observatory has a dial up line for their own bulletin
board system, which also offers many earth/moon/tide/stars/etc.
features.  I don't remember the number right now, but it was
300/1200 baud, and explained itself reasonably well to users.

If all you want is to get the right answers, this system would
serve your need (albeit long distance.)  If you want the software
itself, I would suggest asking someone at the Observatory for
their software, to see what they say.

  --Jim O'Toole

"DanielCWeller"@HIS-PHOENIX-MULTICS.ARPA (11/17/83)

     Does anyone know of the existence of an Earth - Moon simulator that
would, if given a longitude-latitude point on the earth and a time, tell
me the azimuth and elevation readings to the center of the moon from
that point?

     Any help will be greatly appreciated.

     Thanks,
     Daniel C Weller