Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!usc!elroy.jpl.nasa.gov!aristotle!pjs
From: pjs@aristotle.JPL.NASA.gov (Peter Scott)
Newsgroups: sci.space.shuttle
Subject: Re: Various Shuttle/HST questions
Message-ID: <1990Apr6.173743.20338@elroy.jpl.nasa.gov>
Date: 6 Apr 90 17:37:43 GMT
References: <385@mtndew.UUCP>
Sender: news@elroy.jpl.nasa.gov (Usenet)
Reply-To: pjs@aristotle.jpl.nasa.gov
Followup-To: sci.space.shuttle
Organization: Jet Propulsion Laboratory, NASA/Caltech
Lines: 21

In article <385@mtndew.UUCP>, friedl@mtndew.UUCP (Steve Friedl) writes:
> > The HST won't take any pictures of Mercury because it (Mercury)
>   is too close to the Sun for safe pointing.  Is it so close that
>   the camera would *necessarily* be fried, or is it just too close
>   for them to want to take a chance of being off by a couple of
>   degrees?

They *do* plan to take pictures of Mercury, by using the Earth to
occlude the Sun.  After Mercury rises they have 5 minutes to take
a picture and then slew out of the way.  Needless to say they are
going to wait until they have had some practice with the thing before
attempting this maneuver.

>    Naive question #473: why not put additional O rings on the
>    *other* side of the tang so that when the joint rotates, the
>    rings over there get compressed and stop blowby?

Um, isn't this exactly what they did with the redesign?

This is news.  This is your       |    Peter Scott, NASA/JPL/Caltech
brain on news.  Any questions?    |    (pjs@aristotle.jpl.nasa.gov)