[neo_followup] C21E3U2 = interesting object

[Bill Gray]

Hello all,

    If you can follow this object up in the next few hours,
I'd strongly urge you to do so.  It looks as if it could
make a very close approach sometime around 19:00 UTC today.
(It also may turn out to be much less interesting than
that.  We have four observations covering 20.1 minutes;
sweeping claims are difficult.)

    If you look at the MPC's uncertainty maps,  you'll see
that the nominal position is for the "uninteresting" case.
Down to the southwest end of the uncertainty region,  you
start to get the close-approach cases.  I'd suggest looking
there first,  because if it's in that region,  time is of
the essence.  If it's really more distant,  you can look
in the nominal region later,  in a more leisurely manner.
It's that possibility of a close-in shot that ought to get
the attention right now.

    It's quite faint and the uncertainty will grow fairly
quickly,  so I'm not really optimistic here... but it
should definitely be a priority object if you can go to
mag 21.5 or so.

-- Bill