a good telescope, you can begin to appreciate the Hercules cluster for what it really is – a globe-shaped stellar city teeming with hundreds of thousands of stars.
Image: Sky & Telescope
The Hercules cluster (Messier 13) is only somewhat brighter than sixth magnitude, which means it’s just barely bright enough to perceive with the unaided eye. You need a clear, dark night and eagle-eyed vision to see this sixth-magnitude object as a faint speck of light. More than likely, you’ll need binoculars to spot the Hercules cluster.
It’ll be good practice to observe this cluster with binoculars time and time again before searching for a comet that may or may not reach sixth magnitude in brightness. Once you’ve become accustomed to finding the Hercules cluster (Messier 13), try finding Hercules’ fainter globular star cluster, Messier 92. At 6.5 magnitude (the higher the magnitude, the dimmer the object) Messier 92 is somewhere around 1.5 to 2 times dimmer than Messier 13.
Comet Garradd will pair up with the star Lambda Herculis on December 29, 2011, and M92 on February 3, 2012. So think photo opportunity! If you’re able to locate this star or Messier 92, you can use either one to find Comet Garradd on or near those dates.
Sky chart of the constellation Hercules, including M13 and M92
Sky chart: Wikimedia Commons
Tracking down and spotting Comet Garradd with binoculars won’t come easily. I first saw it as a small, faint fuzzball in my 10×50 binoculars on the evening of October 23.
You’ll need a good familiarity with the constellation Hercules and a detailed sky chart to find this comet. (Click here for another sky chart.) Plus, you’ll need a dark, moonless night and perhaps 10 to 20 minutes in the dark to give your eyes time to adapt. EarthSky reader Willow Lepanto sums it up most eloquently: “love chasing something untouchable … and uncatchable.”
But if you’re up for the challenge, Comet Garradd may be yours to behold on dark, moonless nights in December of 2011 and winter of 2012!
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.