Hartley 2 is already visible as a pale green streak in the W-shaped constellation Cassiopeia. NASA astronomer Bill Cooke caught the comet on September 28 in a 4-minute exposure taken from a remotely-controlled telescope in Mayhill, New Mexico (Cooke himself was in his home in Huntsville, Alabama, according to NASA’s Watch the Skies blog).

Several amateur astronomers have taken gorgeous photos of the comet from their backyards in Italy, Austria, Sweden, Louisiana, New Mexico and Arkansas. As the comet approaches, the ghostly green glow should be visible with small telescopes, binoculars and even the naked eye, if the sky is dark enough. A moonless sky on the night of closest approach should make easy viewing in the northeast, especially just before dawn.

October 20 marks the closest approach of Hartley 2 to Earth since its discovery in 1986. But two weeks later, a spacecraft from Earth will get closer still. The NASA EPOXI mission (formerly known as Deep Impact) will fly within 435 miles of the comet’s icy nucleus on November 4 — only the fifth time ever that a spacecraft has been close enough to image a comet’s core.

If you catch any great images of the comet, let us know.

Via spaceweather.com

Images: 1) EPOXI’s view of Hartley 2 on September 5, 60 days before its flyby. NASA/JPL/UM. 2) Bill Cooke, NASA’s Meteoroid Environment Office, Marshall Space Flight Center, Huntsville, Ala.

See Also:

• Comet’s 10 Million-Mile Tail Lights Up in Infrared
• Video: Cold, Little Comet Is No Match for Big, Hot Sun
• Comet Hunter’s Last Look at Earth Is Haunting
• Rare Comet Close-Up Coming to a Sky Near You

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Authors: Lisa Grossman

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