Leo

Leo /ˈliːoʊ/ is one of the constellations of the zodiac, lying between Cancer to the west and Virgo to the east. Its name is Latin for lion, and to the ancient Greeks represented the Nemean Lion killed by the mythical Greek hero Heracles (known to the ancient Romans as Hercules) as one of his twelve labors. Its symbol is ♌. One of the 48 constellations described by the 2nd century astronomer Ptolemy, Leo remains one of the 88 modern constellations today, and one of the most easily recognizable due to its many bright stars and a distinctive shape that is reminiscent of the crouching lion it depicts. The lion's mane and shoulders also form an asterism known as "the Sickle," which to modern observers may resemble a backwards "question mark." ... Leo contains many bright stars, many of which were individually identified by the ancients. There are four stars of first or second magnitude, with render this constellation especially prominent: (1) Regulus, designated Alpha Leonis, is a blue-white main-sequence star of magnitude 1.34, 77.5 light-years from Earth. It is a double star divisible in binoculars, with a secondary of magnitude 7.7. Its traditional name (Regulus) means "the little king". (2) Beta Leonis, called Denebola, is at the opposite end of the constellation to Regulus. It is a blue-white star of magnitude 2.23, 36 light-years from Earth. The name Denebola means "the lion's tail". (3) Algieba, Gamma Leonis, is a binary star with a third optical component; the primary and secondary are divisible in small telescopes and the tertiary is visible in binoculars. The primary is a gold-yellow giant star of magnitude 2.61 and the secondary is similar but at magnitude 3.6; they have a period of 600 years and are 126 light-years from Earth. The unrelated tertiary, 40 Leonis, is a yellow-tinged star of magnitude 4.8. Its traditional name, Algieba, means "the forehead". (4) Delta Leonis, called Zosma, is a blue-white star of magnitude 2.58, 58 light-years from Earth. Epsilon Leonis is a yellow giant of magnitude 3.0, 251 light-years from Earth. ... Leo contains many bright galaxies; Messier 65, Messier 66, Messier 95, Messier 96, Messier 105, and NGC 3628 are the most famous, the first two being part of the Leo Triplet. The Leo Ring, a cloud of hydrogen and helium gas, is found in orbit of two galaxies found within this constellation. [Leo (constellation). Wikipedia]