Hi Lawrence,

I gather you're wondering what _MPC_ is looking for,
rather than what _Guide_ is looking for?

I went to MPES, entered C/2007 W1, and got data for the comet.
Dropping the C/ and just entering 2007 W1 worked.

In Guide, I went to Go To... Object Name, and entered
C/2007 W1. (Or, as Bob mentioned, you can generate a list of
comets to a desired magnitude, then click on the one you want.
Or you can use Quick Info; this lists currently bright comets.
Type '2007 w1', and it will jump ahead in the Quick Info listing
and find the comet in question.)

Clay, I think you're thinking of Charon. Specifying an object
name in Charon is somewhat odd; in this case, you have to use
'cC/2007 W1' to tell it that you want to know about a comet named
C/2007 W1. Guide is slightly brighter in this regard, and can
figure out what C/2007 W1 means. (In truth, both really should be
able to figure out that "2007 W1", or any year/letter/number
designation, probably means a comet.)

Bob, Andrea Boattini has been a very busy comet (and asteroid)
hunter: he has also found comets P/2008 O3, C/2008 S3, and
P/2008 T1, as well as recovering P/1892 T1 = 2008 T3 Barnard-Boattini.
Plenty of room for confusion here, which is probably why MPC
prefers use of the year/letter/number designations.

-- Bill