[guide-user] Scope xtrol, occultations, etc.

Bill J. Gray Jan 24, 2000

SCOPE/LX200 CONTROL:

Andre Germain asked about inventing LX-200 commands... I suppose the
answer would be 'yes and no'. I suppose I could add some commands that
would be sent by Guide to your hardware, and anyone who wanted to could
build hardware using those commands. I'd have little hope that Meade would
agree to include those commands in new versions of their products, though.
They never listen to me as much as they should <grin>.

If you're interested in seeing the entire LX-200 command set, it's
been documented on-line:

http://www.mailbag.com/users/ragreiner/index.html#Index

"...Darn, if only the scope manufacturers agreed to a standard format;
it's the Beta & VHS story of sorts." True. I can't blame people for
avoiding the Meade format. Ideally, I'd want a format with higher
resolution (ignored by most scopes, of course!) and commands to set
slewing rates. But again, Meade doesn't listen well.

WORLDWIDE OCCULTATIONS:

Stephen, thanks for the URL for asteroid occultations. I grabbed that
file and put it into Guide's .ETB ("extended table") format so it would
appear in Tables... Miscellaneous. For the moment, it can be downloaded at

http://www.projectpluto.com/worldocc.zip (about 18 KBytes)

I just put all the events in there. Each event has a 'region number',
so sifting out events for a given region is trivial.

GSC MAGNITUDES/PHOTOMETRY:

Matt Dawson mentioned in passing that "...as discussed elswhere on
the Guide website the magnitudes based on GSC etc are somewhat dodgy
anyhow." Yes... though that's putting it mildly. I think Brian Skiff
once made a comment along the lines of: "Don't use GSC magnitudes for
anything. No, not anything."

I have hopes of making them less embarrassing, as discussed at

http://www.projectpluto.com/gsc_phot.htm

It's slow going, though, and I'm not sure the end result will justify
the effort.

DISTANT URANIAN SATELLITES:

You may have heard that, last summer, three new tiny satellites were
found orbiting Uranus. I wanted to see if Find_Orb could determine orbits
for them, but couldn't get hold of the astrometry. That data is now
available, and those interested in a moderately challenging exercise in
orbit determination might want to try their hand at fitting an orbit for
these very strange objects. Details are at:

http://www.projectpluto.com/cassini.htm#uranian

-- Bill