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Lava Planet

May 6, 2021

A trip to a super-Earth orbiting a star in Pisces would be super-quick. Under daytime temperatures of more than 5500 degrees Fahrenheit, you’d be vaporized in moments.

K2-141b is about half again as wide as Earth, and five times as heavy. And like Earth, it’s made of rock and metal. It orbits less than a million miles from its sun, K2-141. At that distance, it’s “locked” so that the same hemisphere always faces the star, just as the same hemisphere of the Moon always faces Earth.

A study last year outlined what must be happening on the planet.

Under the never-ending glare of the star, rocks on the dayside would melt. That would form an ocean of molten rock that might be dozens of miles deep. Lava at the top of the ocean would vaporize, forming a thin atmosphere of sodium and compounds made of silicon.

At the “twilight zone” between day and night, winds would blow toward the nightside at thousands of miles per hour. Under the darkness of night, the atmosphere would condense and form clouds of liquid metal, which would then “rain” onto the surface. Currents in the ocean would carry material back around to the dayside, continuing the cycle on this super-hot super-Earth.

Pisces is nudging into view in the east at first light. Tomorrow, it’s above and to the left of the crescent Moon. K2-141 stands above the Moon. But it’s so faint that you need a telescope to see it.

Script by Damond Benningfield

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