Constellation: Leo

Leo

Leo (10 August-16 September)

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 (Unicode ♌).

Leo constellation lies in the northern sky. It is one of the zodiac constellations and one of the largest constellations in the sky.

Leo represents the lion and is usually associated with the Nemean lion in Greek mythology. Its symbol is . The constellation was first catalogued by the Greek astronomer Ptolemy in the 2nd century, along with all the other constellations of the zodiac.

Leo constellation is home to the bright stars Regulus and Denebola, the nearby star Wolf 359, and to a number of famous deep sky objects, among them galaxies Messier 65, Messier 66, Messier 95, Messier 96, Messier 105, and NGC 3628.

MYTH

Leo is one of the oldest constellations in the sky. Archaeological evidence suggests that Mesopotamians had a constellation similar to Leo as early as 4000 BC. The Persians knew the constellation as Shir or Ser, Babylonians called it UR.GU.LA (“the great lion”), Syrians knew it as Aryo, and the Turks as Artan.

Babylonians knew the star Regulus as “the star that stands at the Lion’s breast,” or the King Star. Both the constellation and its brightest star were well-known in most ancient cultures.

The Greeks associated Leo with the Nemean lion, the beast killed by Heracles during the first of his twelve labours. Both Eratosthenes and Hyginus wrote that the lion was placed among the constellations because it was the king of beasts.

The lion lived in a cave in Nemea, a town located to the south-west of Corinth. It was killing the local inhabitants and could not be killed because its skin could not be pierced by any weapons.

Hercules and the Nemean lion, photo: Andreas Praefcke

Heracles could not kill the lion with arrows, so he trapped the lion in its cave, grappled with the beast and eventually choked it to death. He used the lion’s claws to cut off its pelt, and then wore the pelt as a cloak, complete with the lion’s head. The cloak both protected Heracles and made him appear even more fearsome.

In the sky, the six bright stars that form the shape of a sickle represent the lion’s head, and the brightest star in the constellation, Regulus (Alpha Leonis), marks the beast’s heart. Another bright star, Denebola (Beta Leonis) marks the tip of the lion’s tail. Algieba (Gamma Leonis) lies on the lion’s neck, even though its name means “the forehead.” Zosma (Delta Leonis) marks the lion’s rump.

FACTS, LOCATION & MAP

Leo is the 12th largest constellation in size, occupying an area of 947 square degrees. It is located in the second quadrant of the northern hemisphere (NQ2) and can be seen at latitudes between +90° and -65°. The neighboring constellations are Cancer, Coma Berenices, Crater, Hydra, Leo Minor, Lynx, Sextans, Ursa Major and Virgo.

Leo contains five Messier objects: Messier 65 (M65, NGC 3623), Messier 66 (M66, NGC 3627), Messier 95 (M95, NGC 3351), Messier 96 (M96, NGC 3368), and Messier 105 (M105, NGC 3379). It has 11 stars with known planets.

Leo belongs to the Zodiac family of constellations, along with Aries, Taurus, Gemini, Cancer, Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius and Pisces.

The brightest star in Leo is Regulus, Alpha Leonis, with an apparent magnitude of 1.35. There are two meteor showers associated with the constellation. The Leonids usually peak on November 17-18 every year and have a radiant near the bright star Gamma Leonis. The January Leonids are a minor shower that peaks between January 1 and 7.

Leo Constellation Map, by IAU and Sky&Telescope magazine

References:

https://en.wikipedia.org/wiki/Leo_(constellation)

http://www.constellation-guide.com/constellation-list/leo-constellation/