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The Constellation Leo, the lion
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Leo

Leo, the Lion, is a very majestic feline. Leo's head and mane are formed by an asterism known as the Sickle which looks like a backward question mark. One of the brightest spring stars, Regulus (Latin for "little king"), is at the base of the question mark. The rest of Leo's body, legs, and tail extend to the east.

Leo harbors a group of galaxies, including two spirals (M95 and M96) and an elliptical (M105), in its central region. With binoculars, the cores of the spirals, but not their faint arms, can be distinguished. M105 appears only as a faint oval-shaped glow. Under the hindquarters of Leo, a spiral galaxy (M66) can be observed. It is nearly face-on, looking like an ethereal galactic pinwheel.

During the dry season in ancient Egypt, the lions of the desert came close to the valley of the Nile when the river flooded, which used to happen when the Sun was in Leo. Some have interpreted this as the origin of the name of the constellation. The ancient Sumerians, Babylonians, Persians, Syrians, Greeks, and Romans, all recognized this constellation as a lion. It was seen as a horse in the ancient Chinese zodiac, and possibly as a puma in Incan lore.

Leo is visible from February through June. Cancer sets to the east and Virgo is to the west. Hydra and Crater are below.

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