May is a good month for going out to spot the constellation of Hercules, but if you find yourself saying, “Mayday Mayday Mayday, I cannot find Hercules,” then read on for a few tricks for locating him.
I freely admit that when I was first learning the constellations, I had problems with Hercules. I just couldn’t pick him out very well. I feel somewhat vindicated by this EarthSky post about Hercules that says,”Hercules the Hero isn’t the easiest constellation to identify. You’ll need a dark sky to see this mighty star figure.” So, ha! Take that, Hercules! It’s not me; it’s YOU! Um, moving on…
The brightest part of Hercules (which still isn’t all that bright) is an asterism called “the keystone.” A “keystone” is an architectural term for a wedge-shaped stone at the apex of an arch, and this shape within Hercules resembles that wedge-shaped stone. It’s rather “trapezoidal,” if you know your quadrilateral shapes. Locating even this keystone of Hercules was a challenge for me at one time. I found it easier to approach him by locating everything else around him first. For example:
- Arc to Arcturus, and find Bootes. A crown (Corona Borealis, The Northern Crown) comes between Bootes and Hercules.
- Hercules is between Vega and Arcturus. A line drawn from Hercules to Arcturus is about twice the length of a line drawn between Hercules and Vega.
- The circlet of Draco’s head is by one of Hercules’s feet.
While those clues may help locate him in general or figure out where his foot is, here is a trick for locating the keystone using the Big Dipper. Use the inner part of the Dipper’s handle (leave out the bent part at the end) and extend the line of the handle until you reach a decently bright star (there are a few really dim ones you’ll cross on the way). This is the lower right star of The Keystone. Your handy-dandy saying to remember this is, “Can you ‘handle’ Hercules?”
If you have been having problems locating Hercules, I hope this helps. Also, below is a star map with lines, labels, and figures so you can see how he fits into the sky with the surrounding constellations. This can be your answer key for the “Finding Hercules” test above. 😉
If you have a telescope, there are a few objects in Hercules you might choose to look for, one being the M13 Globular Cluster, which is easily spotted in small telescopes. It is often described as one of the finest globular clusters visible in the northern hemisphere. Look for it in the Keystone:
Happy starhopping, and good luck handling Hercules!