Scientists Discover A Scorched Planet With A Comet-Like Tail : The Two-Way The planet called KELT-9b is around three times more massive than Jupiter. It orbits a blue star about 650 light-years away from Earth that's nearly twice as hot as our own sun.
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Scientists Discover A Scorched Planet With A Comet-Like Tail

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Scientists Discover A Scorched Planet With A Comet-Like Tail

Scientists Discover A Scorched Planet With A Comet-Like Tail

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  • <iframe src="https://www.npr.org/player/embed/531561840/531629270" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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KELLY MCEVERS, HOST:

Scientists have discovered a giant planet outside of our solar system that's unlike anything they've found before. For one thing, it probably has a tail like a comet. And as NPR's Nell Greenfieldboyce reports, it's also really, really hot.

NELL GREENFIELDBOYCE, BYLINE: So how hot is it?

SCOTT GAUDI: It's so hot that it is hotter than most stars that we know of out there.

GREENFIELDBOYCE: Scott Gaudi led the team that discovered the new world. He's at Ohio State University. He says one side of this Jupiter-like planet is in constant darkness while the other side always faces its star. The dayside surface reaches more than 7,800 degrees Fahrenheit, so hot that not even molecules could survive.

GAUDI: The radiation from the star is blasting the dayside of the planet and heating it up to a temperature that is only 2,000 degrees cooler than the sun.

GREENFIELDBOYCE: The reason this planet is so hot is that every day and a half, it circles a star that's more than twice as massive as our sun. Big, hot stars like this one are actually fairly common. Gaudi says if you just go out and look up at the night sky...

GAUDI: A lot of the stars you can see - in fact, the majority of the stars you can see are either more luminous or hotter than the sun.

GREENFIELDBOYCE: But scientists know almost nothing about the planets around stars like these. That's because in recent years, they've been focusing their telescopes on small, cool stars. It's easier to check planets around those stars to see if they might be friendly enough for life. Gaudi says it took the researchers a couple of years to convince themselves that this new planet really existed.

GAUDI: In fact, I had a bet with my graduate student over a very nice bottle of single-malt scotch about whether the planet was real or not. Just for the record, I won.

GREENFIELDBOYCE: They describe their find in the journal Nature. It's about 650 light years away in the constellation Cygnus. Astronomers can't directly photograph the planet, but they know some things about it.

GAUDI: Its dayside would be very bright orange. Its nightside would be very dark red, and it would have a cloud of evaporating hydrogen and helium which would actually look violet or cyan to your eye.

GREENFIELDBOYCE: That cloud would create a kind of tail like a comet's. And it's possible that eventually the planet's whole atmosphere will get blasted away, perhaps leaving just a rocky, barren core behind. Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF THE BLACK KEYS SONG, "TEN CENT PISTOL")

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