A planet hotter than some of the stars

Astronomers have discovered a massive exoplanet, named KELT-9b, that is hotter than some of the stars. With a day-side temperature of more than 7,800 degrees F. (4,316 degrees C.), it is only about 2,000 degrees F. (about 1,000 degrees C.) cooler than our sun.

This newly discovered planet is three times larger than Jupiter. It orbits a blue star, KELT-9, that is 650 light years away from the Earth. KELT-9 is more than twice as large, and nearly twice as hot, as our sun.  Due to high levels of ultraviolet radiation, the planet may even be shedding a tail of evaporated planetary material like a comet.

Study co-author Keivan Stassun, professor of physics and astronomy at Vanderbilt University says :

KELT-9 will swell to become a red giant star in a few hundred million years. The long-term prospects for life, or real estate for that matter, on KELT-9b are not looking good.

A NASA statement about this planet says that :

Because the planet is tidally locked to its star – as the moon is to Earth – one side of the planet is always facing toward the star, and one side is in perpetual darkness. Molecules such as water, carbon dioxide and methane can’t form on the dayside because it is bombarded by too much ultraviolet radiation. The properties of the nightside are still mysterious – molecules may be able to form there, but probably only temporarily.


Discovery of this planet provide a lot of data regarding stars and the nature of planets that orbit around them.

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