By Mike P. Usher
Ophiuchus is one of my favorite constellations, perhaps because of its tongue twister name and similarly tough to pronounce component stars like Rasalhague. It is commonly represented as a man grasping or perhaps wrestling a large python-like snake. Ophiuchus is one of the original 48 constellations of the ancient Greeks. The snake itself is also a constellation, a rather unique one – Serpens is the only constellation split into two parts. The western part is referred to as Serpens Caput (head) and the eastern part is Serpens Cauda (tail).
Ophiuchus extends downward inside the zodiac into close proximity of Scorpius. Ancient writers noted how he appears about to trample the scorpion and the scorpion is likewise about to sting Ophiuchus. Others have noted that this makes Ophiuchus the 13th zodiacal constellation.
Ophiuchus has a fair number of binocular objects in it due to its proximity to the Milky Way. In particular, note M10 and M12 which are modestly bright globular clusters. M5 is about twice as bright in the nearby Serpens. While you are at it scan the entire Milky Way in this region of the sky – it’s a treat!
Located about halfway between Ophiuchus and Serpens Cauda is a star, normally invisible even in binoculars, that has the interesting habit of exploding every twenty years or so when it becomes dimly visible to the naked eye. At some unknown point in the future it will likely explode one final time as a supernova; this supernova, when it occurs will be bright enough to cast shadows upon the ground!
See you next time!
Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.