From the July 2012 issue

When will Comet Halley next pass near Earth? Are there any other comets that will come close enough to our planet that people in the United States can see it at night?

James Morris, Stockton, California
By | Published: July 23, 2012 | Last updated on May 18, 2023
Comet Halley
Comet Halley will return to the inner solar system in 2061. The world’s most famous comet (officially designated Comet 1P/Halley because it was the first such object astronomers determined to be periodic) revolves around the Sun once every 75.3 years and last appeared in Earth’s vicinity in early 1986. It currently lies more distant from the Sun than Neptune and Pluto and is nearing the far point of its orbit, which it will reach in 2023.

We probably won’t have to wait half a century to see another bright comet. Unfortunately, astronomers can’t tell us when the next great one will appear. Halley is the only short-period comet that regularly becomes bright enough to be obvious with unaided eyes. The most spectacular of these dust-rich balls of frozen gas are making their initial trips through the inner solar system. As their ices are exposed to intense sunlight for the first time, they erupt with activity and often grow long tails.

The list of dazzling newcomers since Halley last appeared in Earth’s sky includes C/1995 O1 (Hale-Bopp), C/1996 B2 (Hyakutake), and C/2006 P1 (McNaught). Over the past few centuries, Earth has averaged roughly one bright comet every decade. So, expect to see at least a few more before Halley makes its next foray into the inner solar system — we just can’t tell you when they will arrive. — Richard Talcott, Senior Editor