Moon Watch

The moon is in a waning (growing smaller) crescent phase. The new moon is Monday, March 11.

The Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) is an innovative wide field imaging facility developed at the University of Hawaii's Institute for Astronomy.

Its prototype telescope, PS1, is now operational on Mount Haleakala on the island of Maui. In June, Pan-STARRS discovered a nonperiodic comet (a comet that will not come back our way). This comet, officially known as C/2011 L4, is predicted to be bright and easily visible early this month.

On Sunday evening, the comet sets a little over an hour past sunset (6:28 p.m.) and is above the western horizon at the end of nautical twilight (7:21 p.m.). On Tuesday evening, the comet will be to the left (south) of the thin crescent moon. Look for it with low-power binoculars if it is not apparent to your eye.

As the month progresses, the comet will move east and fade in brightness.

Comets are very unpredictable, and many comets thought to be "the comet of the century" have turned out to be duds from the public's point of view, though astronomers never think of a comet as a dud. Each is different, and they are always objects of interest for professional study and personal enjoyment.

I hope comet Pan-STARRS is spectacular, but to paraphrase my good friend David Levy, the renowned comet discoverer, comets are like cats - they have tails and do whatever they like.

Another observing challenge is to find Cancer the Crab. Cancer is a faint sticklike figure that in no way resembles a crab. It sits about half way between Gemini the Twins and Leo the Lion. It will be directly south and 75 degrees above the horizon around 10 p.m., a worthy effort after looking for the comet.

Contact Tim Hunter at