Hi all,

I've had a couple of issues nagging me for a while now and I was going to
send a 'help' email to Bill to sort it out, but now that I am on this list,
I might take advantage of this expanded help group.... :)

Back in early December, I downloaded the 6 asteroid/comet orbital elements
files on the CFA webstite hoping to update the elements resident in Guide (I
am an active minor planet occultation observer and I was hoping to improve
on the accuracy of occultation paths). I installed them by placing the
files in the Guide directory and selecting Add MPC Comets/Asteroids as per
the instructions.

However, Guide seems to have taken all the objects to be comets. When I
select 'Go To - Comet' they are all listed there. What I find a little more
disturbing is that Guide plots these MPC asteroids ALONGSIDE the normal
asteroid markers for the same objects - that is I now have 2 Juno's that are
actually quite a long way apart (like 10's to 100's of seconds of arc
apart). I believe that it is the MPC objects (which are labelled
differently and independently of the labelling selection) that are plotted
incorrectly. How do I know? Several minor planet occultations predicted by
Edwin Goffin for this part of the world are well reflected in Guide using
the older asteroid marker while the MPC markers may miss the star by many
seconds of arc.

I think curing the double asteroid problem is easy (delete the MPC sourced
lines in comets.dat - please let me know if this is the wrong thing to do -
I'm not that confident with this sort of thing). I am assuming that this
was not the intended effect of the 'orbital elements update' routine - so
how do I do it correctly ?

The recent discussion re crossreferencing is quite interesting. I was
wondering how Bill manages to crossreference difficult catalogues like the
Washington Double Star list. It must be prone to errors. (Recently while
checking on an asteroid occultation in March for New Zealand that the WDS
reference was not for the star in question but the data is correct in the
actual WDS).

Thanks in advance,

Stephen Kerr
Rockhampton , QLD
Australia.