Re: Two proposed difficult (?) observations

Jim Scotti (jscotti@LPL.Arizona.EDU)
Tue, 30 Sep 1997 09:33:11 -0700 (MST)

> |>2. Let's make plans to try to observe Cassini when it comes 
> |>within 640 km (less than 400 miles) of Earth at about 64,000 
> |>kph (40,000 mph) for a gravity-slingshot boost on its way to
> |>Saturn.  Maybe someone will be able to observe it!
> Somehow I suspect the Cassini NAV folks will be a bit touchy about
> providing data during the flyby...

They may be a bit touchy, but with a properly tuned relationship, they're
usually more than happy to provide look angles.  We're planning to try for
Cassini as it leaves Earth, starting about a week or so past launch.  It's
amazing what one can do with a CCD camera on a 36 inch telescope
(Spacewatch on Kitt Peak).  We should be able to see it far past the
distance we saw Galileo to. 
> As regards observability there are at least two subscribers on this list
> who followed Galileo through it's EGA fly past.

In case you didn't count me, that would be 3 subscribers.  I observed
Galileo when it was 8 million kilometers out during its 2nd flyby at the
end of November 1992.  Faint and difficult, but I think it is a record
distance for an optical detection of a man-made spacecraft.  

We've also imaged NEAR as it left town and Geotail as well as a bunch of
unknowns at large distances (>100,000 kilometers range).  We have a couple
of these iamges (including the Galileo images) on a web page for those who
are interested - follow the "Other images" link from:

Clear skies!


Jim Scotti                              
Lunar & Planetary Laboratory 
University of Arizona                520/621-2717 
Tucson, AZ 85721 USA