Look up with the May 2018 sky map to navigate the stars and constellations in the night sky. On this page is both a color sky map and a black and white printable map to bring outside!
Just click here or on the image below to open the printable map—then bring outside!
Highlight for May: The Largest Constellation
Constellations come in a tremendous variety of shapes, sizes, and levels of brightness. Some are big and bright, like Leo, the Lion, near the center of this month’s sky map. Others are small and dim, like Leo Minor, the Lesser Lion, prowling just above Leo’s head.
Then there is Hydra, the Water Snake. Hydra is a sprawling, twisting star pattern, the largest of all constellations. But with one exception, its stars are faint, making it a challenge to see Hydra’s full extent.
- Start your hunt for the Water Snake by choosing an observing location far from city lights; too much “light pollution” makes Hydra’s dim stars difficult to see.
- Get your bearings by facing south-southwest and finding the Spring Triangle, a trio of bright stars composed of Arcturus, Regulus, and Spica. Even brighter than these three is blazing Sirius, the brightest of all stars, low to the right. A fifth and still brighter landmark is the planet Jupiter, off to the left.
- Halfway between Regulus and Sirius, look for a small, five-sided star pattern. This diminutive pentagon is the head of Hydra. If you can see even four of the five stars in Hydra’s head, your odds are good for seeing the rest of the Water Snake. From the head, the body of Hydra loops down to Alphard, the brightest star in the constellation. “Alphard” means “the solitary one” in Arabic, referring to the absence of other bright stars nearby.
Following the Hydra Constellation
Now the real work begins—attempting to follow the rest of Hydra’s serpentine body across the sky. To do this successfully, use the “star hopping” technique. This involves comparing the sky map to the actual sky, carefully noting the position of each successive star in Hydra in relation to other stars.
Hold the map in front of you and let your eyes move back and forth from the sky to the map as you “hop” from one star to the next. It takes some practice, but with care you can hop the full length of Hydra from head to tail. Star hopping is a tried-and-true method for finding your way around the sky. Astronomers all over the world use the star hopping technique every night of the year.
May 2018 Sky Map
Click here or on image below to enlarge this map (PDF).
Sky map produced using Chris Marriott’s Skymap Pro
There are a couple of interesting sights on the long trek from the head of Hydra to its tail: the constellations Crater, the Cup, and Corvus, the Crow (or Raven). Hydra slithers below both of them in a broad curve before we reach the Snake’s tail to the lower left of Spica.
Hydra, Crater, and Corvus are all part of a myth involving the Greek god Apollo. As the tale goes, Corvus, the Crow, served Apollo a cup (Crater) of water, in which was lurking Hydra, the Water Snake. Irate Apollo banished the crow, the cup, and the snake to the sky, where they are fated to reside for eternity. Few people ever see all of Hydra in one night, due to both the faintness of its stars and the fact that its enormous length means that some part of it is usually hidden below the horizon. The month of May offers a chance to view the entire Water Snake in all its reptilian glory.