cluster that is visible to the naked eye under dark skies. Its shape has been described as "triangular"; this 80-star cluster is unusually large, more than half a degree in diameter, larger than the diameter of the full Moon.[1]Ancient globular cluster NGC 6535.[7]There are several globular clusters in Hydra. M68 (NGC 4590) is a globular cluster visible in binoculars and resolvable in medium amateur telescopes. It is 31,000 light-years from Earth and of the 8th magnitude.[1] NGC 5694 is a globular cluster of magnitude 10.2, 105,000 light-years from Earth. Also called "Tombaugh's Globular Cluster", it is a Shapley class VII cluster; the classification indicates that it has intermediate concentration at its nucleus. Though it was discovered as a non-stellar object in 1784 by William Herschel, its status as a globular cluster was not ascertained until 1932, when Clyde Tombaugh looked at photographic plates taken of the region near Pi Hydrae on 12 May 1931.[8]M83 (NGC 5236), the Southern Pinwheel Galaxy, is an 8th magnitude face-on spiral galaxy.[1] It is easily observed in skies south of 40N latitude, found by using 1, 2, 3, and 4 Centauri as guide stars.[9] It has been host to six supernovae, more than any Messier object. Large amateur telescopes - above 12 inches aperture - reveal its spiral arms, bar, and small, bright nucleus.[1][9] In a medium-sized amateur instrument, around 8 inches in aperture, the spiral arms become visible under good conditions. It is not perfectly symmetrical in the eyepiece, rather, the northwest side is flattened and the nucleus has a southwest-to-northeast bar. A smaller sister to the Milky Way, it is a grand design spiral galaxy 40,000 light-years across.[9]NGC 2865 is relatively youthful and dynamic, with a rapidly rotating disc full of young stars and metal-rich gas.[10]There are many other galaxies located in Hydra. NGC 3314, usually delineated as NGC 3314a and NGC 3314b, is a pair of galaxies that appear superimposed, despite the fact that they are not related or interacting in any way. The foreground galaxy, NGC 3314a, is at a distance of 140 million light-years, and is a face-on spiral galaxy. The background galaxy, NGC 3314b, is an oblique spiral galaxy, and has a nucleus that appears reddened because of NGC 3314a's dusty disk.[11] ESO 510-G13 is a warped spiral galaxy located 150 million light-years from Earth. Though most galactic disks are flat because of their rate of rotation, their conformation can be changed, as is the case with this galaxy. Astronomers speculate that this is due to interactions with other galaxies.[12] NGC 5068 may be a member of the M83 group, but its identity is disputed. It has a low surface brightness and has a diameter of 4.5 arcminutes. It is not perfectly circular, rather, it is elliptical and oriented on a west-northwest/east-southeast axis. However, it is of fairly uniform brightness throughout.[13]Meteor showers[edit]The Sigma Hydrids peak on December 6 and are a very active shower with an unknown parent body.[14] The Alpha Hydrids are a minor shower that peaks between January 1 and 7.[15]History and mythologyWestern mythologyHydra and surrounding constellations, from Urania's