Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site jplgodo.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!ittatc!dcdwest!sdcsvax!sdcrdcf!oberon!smeagol!jplgodo!steve
From: steve@jplgodo.UUCP (Steve Schlaifer x3171 156/224)
Newsgroups: net.space
Subject: Re: "At the moment Uranus's south pole points..."
Message-ID: <578@jplgodo.UUCP>
Date: Mon, 24-Feb-86 18:53:18 EST
Article-I.D.: jplgodo.578
Posted: Mon Feb 24 18:53:18 1986
Date-Received: Sat, 1-Mar-86 00:44:32 EST
References: <860217-235409-1418@Xerox> <399@utastro.UUCP>
Organization: Jet Propulsion Labs, Pasadena, CA
Lines: 18
Summary: IAU doesn't use right hand rule

In article <399@utastro.UUCP>, ethan@utastro.UUCP (Ethan Vishniac) writes:
> The angular momentum vector of the Earth points toward the North Celestial
> Pole.  Put it another way, looking down on the Earth from a point above
> the North Pole the Earth's rotation is counterclockwise.  Therefore,
> by convention, the north pole of any planet is that pole from which
> the rotation appears counterclockwise.
Unfortunately, the IAU (International Astronomical Union) didn't see it that
way.  Essentially, they decided that the north pole is the one above the 
invariant plane (ecliptic) regardless of which way the planet spins.  It's
going to be lots of fun when we get really interested in asteroids and 
comets :-(
-- 

...smeagol\			Steve Schlaifer
......wlbr->!jplgodo!steve	Advance Projects Group, Jet Propulsion Labs
....group3/			4800 Oak Grove Drive, M/S 156/204
				Pasadena, California, 91109
					+1 818 354 3171