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There is evidence that a planet around a distant
star lost its atmosphere ― then gained a

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second one through volcanic activity, according
to scientists using NASA’s Hubble Space Telescope.

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The planet, GJ 1132 b, is hypothesized to 
have begun as a gaseous world with a rocky core.

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Starting out at several times the diameter
of Earth, this so-called “sub-Neptune”

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quickly lost its early hydrogen and helium
atmosphere due to the intense radiation of

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the young, hot star it orbits.

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Then the planet was stripped down to a bare
core about the size of Earth. And that’s

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when things got interesting.

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To the surprise of astronomers, Hubble observed
an atmosphere which, according to their theory,

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is a “secondary atmosphere” that is present
now. Based on a combination of direct observational

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evidence and inference through computer modeling,
the team reports that the atmosphere consists

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of molecular hydrogen, hydrogen cyanide, and
methane, and also contains an aerosol haze.

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Scientists think hydrogen from the original
atmosphere was absorbed into the planet’s

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molten magma mantle, then slowly released
through volcanic processes to form a new atmosphere.

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Though this hydrogen continues to escape into
space, the secondary atmosphere is replenished

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by volcanic gases that seep through cracks
in the planet’s thin crust.

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Scientists are wondering how many other planets
might have started out as gas giants but became

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smaller and rocky after their early atmospheres
evaporated away.

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Astronomers hope to use the upcoming James
Webb Space Telescope’s infrared vision to

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detect hot areas of volcanic activity on the
planet.

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GJ 1132 b might be orbiting a distant star
41 light years away, but thanks to the Hubble

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Space Telescope, it just got a little
bit closer.

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[ SILENCE ]