Bernd Brinkmann asked about removing duplicate comets such as (73P)
Schwassmann-Wachmann 3. The thing to do here is to make sure that the
new comet file you add actually contains the text "(73P)". Guide will
look at that comet designation, rather than the discoverer's name. But
if it sees (73P) as part of the comet's designation, it'll know that it
should remove the original (73P).

That will work just fine in this particular case. Bernd also
mentions 173P/Mueller = P/2005 T1 and 171P/Spahr = P/1998 W1. Here,
there's a complication: the comet _was_ known as P/1998 W1, for
example, and then got a permanent designation. I've yet to resolve
that particular headache.

Comets have been a headache for some years now. Ideally, I'd be
able to direct people to a comprehensive list of all comets, resembling
the ASTORB and MPCORB databases for asteroids. But the lists of which I
am aware are the MPC's comet list (only recent objects) and the JPL
DASTCOM list (contains most objects, but not all, and doesn't give
magnitude data.) So Guide has to splice the MPC "current comet" list
onto its own "historic comet" dataset. And sometimes, the splicing
isn't perfect. Designation systems change (73P used to be known as
Schwassmann-Wachmann 3, for example... still _is_ known as that in some
lists, such as the JPL one.)

-- Bill