Comet Hartley 2 Visible in Morning Sky This Week

Contact: Rebecca Johnson
Editor, StarDate magazine
512-475-6763; [email protected]


Photo, JPEG (1797x1225)1.64 MB
Finder chart, TIFF (1880x1289)6.96 MB

The small comet Hartley 2 makes its closest approach to Earth on Wednesday, and should be visible to the unaided eye under dark skies in the hours before dawn, according to the editors of StarDate magazine. Early risers can take a look at the comet in anticipation of its November 4 encounter with NASA's Deep Impact spacecraft.

Comet Hartley 2 finder chart

Comet Hartley 2 (green, right center) as seen from near McDonald Observatory on October 8, 2010. On this date, the comet appeared to the right of the Perseus Double Cluster.To view the comet this week, look northwest before dawn, about 75 degrees above the horizon — almost directly overhead. Hartley 2 will be near the bright star Capella, in the constellation Auriga, the charioteer.

The nearly full Moon will set about two hours before the Sun rises, allowing about 90 minutes of prime comet-viewing time. If you have difficulty viewing the comet, which is small and dim, try using binoculars.

Australian astronomer Malcolm Hartley discovered the comet in 1986. Less than a mile wide, it orbits the Sun every 6.5 years. On Wednesday, it will come within 11 million miles (18 million km) of Earth. The comet will make its closest approach to the Sun on October 28.

On November 4, Deep Impact will fly by the comet at a distance of about 430 miles (700 km), at a speed of 7.6 miles per second (12.3 km/sec). The probe will use a suite of instruments to study the comet's composition.

Published bi-monthly by The University of Texas at Austin McDonald Observatory, StarDate magazine provides readers with skywatching tips, skymaps, beautiful astronomical photos, astronomy news and features, and a 32-page Sky Almanac each January.

Established in 1932, The University of Texas at Austin McDonald Observatory near Fort Davis, Texas, hosts multiple telescopes undertaking a wide range of astronomical research under the darkest night skies of any professional observatory in the continental United States. McDonald is home to the consortium-run Hobby-Eberly Telescope, one of the world's largest, which will soon be upgraded to begin the HET Dark Energy Experiment. An internationally known leader in astronomy education and outreach, McDonald Observatory is also pioneering the next generation of astronomical research as a founding partner of the Giant Magellan Telescope.


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