A comet named PANSTARRS is overhead right now and visible to the naked eye, when the evening skies are clear. Here's what you need to know:

Viewing

Find a clearing with a sky open to the west, approximately on a line with the Ravenel Bridge looking toward the Charleston peninsula. Good spots include waterfront sites such as Brittlebank Park or Waterfront Park in Mount Pleasant.

The comet will be at its visible peak this week, from about 7:30-8:30 p.m. as it sets after the sun.

Look for a fuzzy ball or star with a short tail shooting straight up, away from the sun. It could be about the size of a star or it could be as large as the Pleiades star cluster, which is the most obvious cluster to the naked eye.

Tonight's skies might be cloudy in the west. Wednesday night might offer the first clear views. The crescent moon will set just above the comet.

Binoculars will provide a better view. The College of Charleston on Friday holds an open house at its astronomy observatory starting at 7:30 p.m. to view the comet. The observatory is located in the Hollings Science Center, 58 Coming St. For more information, email truec@cofc.edu or call 843-953-2031.

Vetting

Comets are icy celestial bodies that spew gas or dust as they orbit.

They usually are named for their discoverers. PANSTARRS is named for the remotely operated telescope that found it.

A visible comet is fairly rare, occurring maybe once every 10 years.

Comets are largely unpredictable. “They are random visitors from space most of the time,” said Terry Richardson, College of Charleston astronomy professor. How visible one is during any given pass “depends on how much gas is cooking out of it.”

A superstition surrounding comets is that they are bad omens. A comet was visible for the assassination of Julius Caesar in 44 B.C., the eruption of Mount Vesuvius in 1631 and the worst of the bubonic plague in London in 1665. Cults announced the 1973 arrival of Comet Kohoutek as the end of the world. The visibility of the ballyhooed comet was a bust; so was the prediction.

Sources: Terry Richardson, College of Charleston; starryskies.com