This May will be a great time to see a collection of double stars that the sky has to offer! If you just want something else fun to see and test your eyes while watching the Lunar Eclipse on the 15th or just want to stargaze any random night in May read this guide and we’ll explore some of the best pairs of stars the sky has to offer.
The May sky has the Big Dipper, the twins of Gemini, and Leo the lion all beautifully overhead. Without looking at the chart at the end of this article (no cheating) can you tell which star of the seven in the Big Dipper are actually two stars? This was used as an eye exam in the Roman military. If you could pick out the star in the Big Dipper that was actually two stars with the naked eye you could pass the eye exam..... do you have a guess? Check again just to be sure.... ok hint it's in the handle.... sure of your guess now... Okay, If you picked the middle star of the handle, great news you have good eyes!
In India they also saw Mizar as these two stars and used them to represent a married couple Arundhati. At a Hindu wedding ceremony the priest might show the newlyweds this star and tell them how it represents a marriage where both stars put their light together and shine brighter as one. Looking even closer In a telescope or binoculars (or the photo at the top of this post) you might be able to see one of these stars are two stars also!
It’s actually very common for stars to have companion stars, about 60% of stars have companion stars. Our Sun is actually in the minority for being alone. It's when you drive a desert highway at night you might see one on coming headlight on the horizon but as you get closer you'll see it split into the two headlights. the telescope is getting you close enough to see it as two stars.
Star charts to help you find Leo
Overhead and slightly to the east you will see Leo the lion! I really like this constellation because Leo is one of the rare ones that actually looks like what it’s supposed to. Leo is a lion doing a sphinx pose (it’s actually thought that the sphinx in Egypt was modeled after Leo because of how similar they are). You’ll see a bright star directly overhead just a tad south from the Big Dipper that’s Reglus, the brightest star in Leo and represents the heart of Leo. above reglus is a little C shape of stars (to me it looks like a backwards question mark “؟” if you include reglus) that’s the mane of Leo the lion. In front (to the West) of Reglus is a star representing the front paw of the lion. Behind (to the east) of Reglus are three stars of similar brightness making the back leg of Leo and the fluffy part at the end of the Lion’s tail.
Leo has an even harder eye exam. Can you see the double star in Leo with the naked eye? I personally find this one harder. Where the one in the big dipper I see right off the one in Leo I can kinda see it knowing where it is but IDK if I would have ever actually seen it myself.... give it a try.... do you have a guess? want a hint again? hint: it's in the mane... ok now you really hive it? it's the brightest star in the mane (see star chart below). For me I couldn't see it on my own but when it was pointed out to me I can kinda see it but I feel like I'm tricking myself into seeing it.
Looking west you will easily see two stars, the Twins of Gemini, Castor and Pollux. These two stars are much easier seen as they are much further apart. The legend is Pollux (the southern of the two stars) was granted immortality by Zeus but Castor was not. Once Castor passed away Pollux was so stricken by grief that he told Zeus he could not live on forever without his brother. Zeus made Pollux a deal that both brothers could live on forever together in the celestial sphere and placed them together in the sky. You can make the twins by imagining little stick figures under (to the west of) the stars.
Drawing a line overhead starting with Gemini and going to the big dipper you will see a line of two stars that get closer and closer together. These are the deer tracks. There's a Native American legend that these are the tracks left behind by a deer. Unfortunately since they end kind of near Leo the lion we can kind of assume that the fate of the deer was to become dinner for the lion.
Just between the Twins of Gemini and Leo you will find M44, the Beehive Cluster (located in Cancer). This is easily visible to the naked eye under dark clear skies (and a good way to test your eyes during the upcoming eclipse this May).
Pre-telescope astronomer Ptolemy described it as a "nebulous mass", It almost looks like a fainter Seven Sisters or a stray drip of the milky way. Much like the Seven Sisters this is an open cluster. In binoculars/telescopes you will see it’s actually about a thousand stars. This open cluster is about 577 light years away, I think of it like a Small town of stars just down the road (577 ly is ‘just down the road’ in cosmic terms).