Thanks to James B. Kaler. These contents are the property of the author and are reproduced from original without the author's express consent because of fair use and valid educational purposes.
Great Leo , which dominates northern spring skies, contains three stars of note, bright Regulus, second magnitude Algeiba, which shares the "Sickle" with Regulus, and second magnitude Denebola. Denebola, Leo's Beta star, is the easternmost of a prominent triangle of stars set to the east of Regulus. It provides us with the Lion's tail, the name coming from the Arabic phrase that means exactly that. Denebola is a classic white star of temperature 8500 degrees Kelvin, and is similar to summer's first magnitude Altair, but at a distance of 36 light years it is twice as far away and therefore dimmer to the eye. Like all the brighter naked eye stars, Denebola is more luminous than the Sun, emitting 12 times the solar energy. It is one of a fairly rare "Vega" class of stars that is surrounded by a veil of infrared- emitting dust. Since the planets of our Solar System were apparently created from a circumstellar dusty cloud, such dust implies the possibility that Denebola might have planets as well, though there is no direct evidence for them. Denebola is also a subtle variable star of the "Delta Scuti" type. Such stars vary in brightness by small amounts over periods of only hours. The star shows no evidence for any kind of stellar companion.