Deep Impact is set to fly by Earth tomorrow, December 31, the first of three flybys it'll have before its encounter with comet Hartley 2 on October 11, 2010, and a few observers have already spotted the spacecraft on its inbound trajectory. The Astronomical Observatory of Farra d'Isonzo was the first to pick it up, on the 27th, and yesterday Richard Kowalski reported that despite poor weather conditions, the Catalina Sky Survey's 1.5-meter telescope detected it too. Spotting Deep Impact as it flies by could be a fun challenge for those of you who have the equipment necessary to see a faint, magnitude 20 object. The EPOXI website ("EPOXI" is the name of the Deep Impact extended mission) has lots of details on where to look. This time, the incoming spacecraft was not mistaken for a potentially hazardous object, as happened with Rosetta last month -- that incident must have been fresh in everybody's minds!