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Spring brings flowers... and galaxies. Perhaps the best known of the spring galaxies are those found in the Virgo Cluster, but this month we will take a trip off the beaten path and visit the largest constellation in the entire sky. Hydra the Water Snake stretches over 90 degrees across the sky and contains more than 1300 square degrees. There are several galaxies worth a look in Hydra, and some other interesting objects too. The head of Hydra is a distinct pattern, located south of the dim stars of Cancer. The head is in the southwestern sky after dusk in mid-May. Try to view the head area early in the month. Southeast of the head is bright Alphard, shining at magnitude 2. Alphard means "the lonely one", because it is the only bright star in this part of the sky. You can also go south of the stars of Leo (and this year, bright Jupiter), to find the neck of Hydra. Further east, the constellations Corvus the Crow and Crater the Cup seem to ride on the back of Hydra.
One of the stories behind Hydra involves these constellations. It tells of how Apollo sent the raven, or crow, to collect water in the nearby cup. But the bird wasted its time eating figs. Then, as an excuse for losing time, it gathered up the Water Snake (Hydra) in its claws and flew back, telling Apollo that this creature was the reason for its delay. Apollo would have none of it, and threw all three: the crow, the goblet, and the water snake, into the heavens. For penance, the crow was made to suffer eternal thirst (and this makes the bird caw raucously instead of sing like normal birds). Another story involves the famous Hercules and one of his 12 labors. Hydra was portrayed as a beast with the body of a hound and 100 serpentine heads. When Hercules fought Hydra, he found that every time he cut off a head, three more grew back in its place. To counteract this he had his charioteer, Iolus, burn the stump of every cut off head, which prevented them from growing back. However, the last head was immortal, so they trapped it under a rock after cutting it off. For more spring sights, visit our Corvus Page.

Some information from this article was taken from Chris Dolan's Stars and Constellations Page.

To see the entire map above, visit Orion Telescope.



In this larger, more detailed view, we'll take a closer look at some of the interesting sights in Hydra. Our tour goes from west to east, which is right to left on this map. The symbols below show how an object is best viewed:

with your naked eye;

with binoculars, and

with a telescope.

NGC 2775. This is a fairly bright, fairly large spiral galaxy, located about 4 degrees east of Zeta (z) Hydra. It is magnitude 10.3 and 4.5 arcminutes in diameter. a 6 or 8 inch telescope should show the bright core of this galaxy, and maybe some detail in the spiral arms. Click here for more info on NGC 2775, including a great picture.

NGC 3115, the Spindle Galaxy. This galaxy is definitely big and bright. The Spindle shines at magnitude 9.2 and its size is 8.3 arcminutes. It lies about 3 degrees east of the 5th magnitude star Gamma (g) Sextans. Through the telescope it is seen edge on, with a central bulge similar in appearance to NGC 4565.

NGC 3166 and 3169. These galaxies are actually located in Sextans, about 4 degrees northeast of the 4.5 magnitude star Alpha (a) Sextans. The two galaxies themselves are only separated by only 6 arcminutes (remember, there are 60 arcminutes in one degree). Both are magnitude 10.5 and appear as slightly elongated blobs through the eyepiece.

NGC 3242, the Ghost of Jupiter. This planetary nebula is also called the Eye Nebula because of its appearance in photographs. Its located almost 2 degrees west of Mu (m) Hydra. It has a visual magnitude of 7.7 and should show up well in most small to medium aperture telescopes. It is nicknamed the Ghost of Jupiter because it is about the same size as Jupiter, roughly 40 arcseconds. More info on NGC 3242

Beta (b) Hydra. A very close double star. The magnitude of the brighter component is 4.7, and the fainter is 5.5. They are separated by only 1 arcsecond, making the pair a test for your telescope's optics. How much magnification does it take for you to split this pair?

M 68. This rich globular cluster is only half a degree east of a 5th magniutde star in Hydra, and 3 and one half degrees south of Beta (b) Corvus. Because of its southerly declination, it can be a hard target for Northern Hemisphere observers, but it should still show up as a faint patch in binoculars. It takes a 6 inch scope from a dark site to resolve this cluster into individual stars. More info on M 68. Also check out nearby galaxy M 104. More info about it can be found on our Corvus Page.

M 83. Although one of the most picturesque galaxies in the night sky, M 83 is another hard target for northern hemisphere observers because it is so far south. Its magnitude is 7.6, but it is a large face-on spiral, which means its brightness is spread out over a large area. The best way to find it is to use the little triangle of stars to the south of M 83. Its located about 3 and one half degrees north of the closest star to it in the triangle. More info on M 83.

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