Comet Machholz, C/2004 Q2, continues to brighten on schedule as it moves toward the northern sky. On the evening of Sunday, December 5, 2004, several Sky & Telescope editors observed it independently from locations around Boston, Massachusetts. It was an easy find in hand-held binoculars despite the fact that it lay deep within the skyglow of Boston. In a 4-inch refractor it appeared like a major globular cluster, at least 15 arcminutes in diameter, but with an intensely bright, nearly stellar core.
Several people at dark sites have reported the comet as faintly visible to the naked eye, making it a record-breaking fifth such comet in 2004, following NEAT (C/2001 Q4), LINEAR (C/2001 T7), Bradfield (C/2004 F4), and LINEAR (C/2003 K4). Recent brightness estimates cluster around magnitude 5.5, almost half a magnitude brighter than predicted, and the comet sports an extremely faint dust tail one or two degrees long as well as the ion tail shown in the photograph above.
Update: Just before midnight on December 13th, Night Sky editor J. Kelly Beatty got a good look at the comet from his home northwest of Boston. He noted that while it was easy to spot in his 7x35 binoculars, Comet Machholz was marginal through a 6x30 finder and impossible to see naked-eye in his suburban sky (which has a limiting magnitude of about 4.) He reported no hint of a tail.