The Ghost Hunt’s 109 targets

Each spring, amateur astronomers around the world challenge themselves by competing in the Messier Marathon — a visual feat in which observers use their telescopes to view all 109 celestial objects cataloged by French comet-hunter Charles Messier in a single night. This dusk-to-dawn romp has been a popular annual event since the 1960s. The search is fun and gratifying, and it helps observers hone their hunting skills.Why not double the fun by hosting a similar challenge in the autumn? I have created a list of 109 deep-sky objects that you can hunt down in a single night on or around the New Moon closest to Halloween. In deference to the time of year, and considering that many deep-sky objects appear as pale specters of fuzzy light, I decided to call this October treat the Ghost Hunt.

Like the Messier Marathon, the Ghost Hunt is intended to be a fun and challenging activity that lasts from dusk to dawn. But there’s one big difference: What you’ll search for in the Ghost Hunt are not just Messier objects but 109 targets carefully selected from several deep-sky object lists.

The Ghost Hunt features 25 open star clusters, 27 galaxies, 16 emission nebulae, four reflection nebulae, 19 planetary nebulae, 14 globular star clusters, three supernova remnants (including two segments of the Veil Nebula), and one dark nebula. While nearly 70 percent of the objects in the Ghost Hunt are not Messier objects, they should be no more challenging to see. The PDF file you can download at the bottom of this page lists their locations, types, magnitudes, and apparent sizes.

In 2010, the New Moon closest to Halloween falls on Saturday, November 6. So that weekend would be the best time to hold a Ghost Hunt. The weekend beginning Friday, October 29 would also be good because the Last Quarter Moon won’t rise until around 1 a.m. local Daylight time. And it will be at least an hour later before its light begins to interfere with your observing.

As your guests admire the Ghost Hunt’s sights, explain to them how, owing to the vastness of space and the limited speed of light, we can travel back in time by simply looking up at the night sky. When it comes to astronomy, the past is very much alive. And it will remain so far into the future.