Bright planets make the best guides to other objects in the night sky. Jupiter for instance is perfectly positioned to point us to Scorpius the scorpion. Outside of the moon it’s now the brightest object in the evening sky and will remain so for the summer. It shines beacon-like in the southern sky at dusk for much of the summer. If you’ve ever seen the space station, that’s how bright Jupiter is.
We’ve talked before about using a small telescope to view the planet’s four brightest moons and dark clouds belts including the Great Red Spot. I encourage you to do so any clear night. This time, we’ll follow its lead to Scorpius, one of the few constellations that resembles its name. Scorpius has deep roots, all the way back to ancient Greece, and represents the mythological scorpion that fatally stung Orion the hunter. That’s the reason the two groups lie in opposite parts of the sky — as Orion sets his nemesis rises.
Once you’ve found Jupiter, look a fist to its right and you’ll spot Antares, a bright, red supergiant star. Color gives it away. From Antares we’ll “connect the dots” to perfect place to start to join the dots of the rest of the constellation. About three fingers (held against the sky) to the upper right of Antares you’ll see Graffias, Dschubba (zhubba) and Fang which together form the head of the scorpion. They’re a little like Orion’s Belt but make a vertical line instead of a horizonal one.
Antares, whose name means “Anti-Ares” or “Not-Mars” (Ares is the Greek name for Mars, and the two have nearly the same color), is one of the most amazing stars in the sky. Although not apparent to the eye because of its tremendous distance (604 light years), Antares is 700 times the size of the sun. If you put Antares in its place it would engulf all the planets through Mars. Take that Ares! Like Betelgeuse in Orion, Antares will someday, perhaps even in our lifetimes, explode as a supernova.
Antares represents the “heart” of the scorpion. If you now connect the brightest stars below it according to the map, they form its abdomen and tail which resemble a fishhook or the letter J. After you reach to bottom of the figure, the abdomen curls back up to form a tail ending with the “stinger,” a star named Shaula. Skywatchers in the central and southern U.S. can see the entire scorpion with ease, but if you live in the northern states, the bottom of the tail scrapes along the southern horizon and may not be visible. As long as you have a notch in the tree line, the stinger star isn’t too difficult to pick out even from northern Minnesota. If you can locate it, you’re in luck because there are two bright star clusters nearby.
Point your binoculars above and left of Shaula to find two beautiful star clusters, one named for Claudius Ptolemy, an Egyptian astronomer of the Roman Empire era, and the other for its butterfly-like appearance. They’re both faintly visible with the naked eye and lovely sights in binoculars or a small telescope. What’s nice is that even in binoculars you can see individual stars in both clusters instead of fuzzy masses.
If you now work your way back up the tail, place Antares in the binoculars and look for a fuzzy patch or glow a bit more than 1° to its right (west). That’s M4, one of the nearest globular clusters to the solar system with a distance of 7,200 light years. If your skies aren’t too light polluted you should have no problem seeing it in a pair of 40mm or 50mm aperture binoculars. You’ll need a 6-inch telescope to break down M4’s “fuzz” into individual stars, of which there are more than 100,000.
Continuing up past M4 and Antares we arrive again at the scorpion’s head. The topmost star, Graffias, is a spectacular double star for small telescopes. Just 30x to 40x should split it into two separate stars in orbit about one another. Next down is Dschubba or Delta (δ) Scorpii, located 400 light years away. Dshubba is a close double star that occasionally undergoes dramatic eruptions that can notably change its brightness over a decade. The last time this happened was in 2000 when the star gradually grew brighter until it nearly rivaled Antares. It’s fluctuated in brightness since then and still hasn’t settled back into its “quiet” state.
I hope you enjoyed this tour of Scorpius and will find an opportunity to include it your constellation menagerie.