Your Night Sky for May 27, 2020

Hercules the Kneeler

If you found Coma Berences and Bootes, then you know how to look in the sky. On the other side of Bootes is Corona Borealis, the Northern Crown. If you look up in the east, it will be just below Bootes. Since Bootes is very high in the sky, Corona Borealis will also be high.


It’s a 7 star constellation that’s a half circle open to the left which will be NE.  When you find it, you will always remember it since it’s a distinct formation of stars. June and July are the months for best viewing of it, so this is the time to look for it although it’s visible until October. Even though it’s small and relatively dim, it’s easily identifiable in a clear dark sky like ours.


The size is a fist held up high. It has one really bright star Alphecca, which is the top of the right side of the middle stars which is a blue white star 60 times brighter than our sun and is 75 lightyears from us. It also contains more than 400 galaxies. Since they’re 1.5 billion lightyears away, none are brighter than magnitude 16. So you’ll need a strong telescope to view them. There are also double stars and variables, which periodically vary in brightness. So if you use binoculars or a telescope, you should find some interesting things.


Just below the Northern Crown is Hercules. He’s the fifth largest constellation in our sky. There is a square body in the center with his head and arms to the right, and his legs spread out to the left. When you look at him from the east, he’s lying on his side. And if you look from the south, his head will be at the bottom with his legs up high. Unfortunately it’s not very bright, but since our sky is dark and clear, you should be able to find him.


Rasalgethi is his head star and is his brightest. The name is an old Arabic work meaning “head of the kneeler.” It has a unique red hue of a supergiant star. What’s common for red giant stars is their brightness frequently varies. It’s also called Alpha Herculis and is a double star system. The other star is actually brighter since it doesn’t change and is more visible due to that, but sometimes you can see both stars. They’re 380 lightyears away. If you look from the south and he’s got his head on the bottom, and it will be the lower center star. If he’s on his side, it will be the center right star.
His most distinctive feature is actually the Keystone, which is the group of 4 stars that make up his body. When he’s on his side, the upper center of his body contains the spectacular globular cluster M13. It contains a group of 300,000 closely packed stars that are 25,000 lightyears away. With binoculars they’ll be just a fuzzy ball, but a telescope will show you a lot more. So when you have a chance, go out and look at these constellations. Now that the sky stays lighter longer, you won’t see many stars until after 9 p.m.