About 30 light years away, a Neptune-sized planet is having some of its layers peeled back. Astronomers using NASA’s Hubble Space Telescope have discovered an immense cloud of hydrogen evaporating from a Neptune-sized planet named GJ 436b.
The planet’s atmosphere is evaporating, say scientists, because of extreme irradiation from its parent star — a process that might have been even more intense in the past.
David Ehrenreich of the Observatory of the University of Geneva in Switzerland is the study’s leader. He said:
The parent star, which is a faint red dwarf, was once more active. This means that the planet’s atmosphere evaporated faster during its first billion years of existence. Overall, we estimate that the planet may have lost up to 10 percent of its atmosphere.
GJ 436b is considered to be a “Warm Neptune” because of its size and because it is much closer to its parent star than Neptune is to our own sun. Orbiting at a distance of less than 3 million miles, It whips around the central red dwarf in just 2.6 Earth days. For comparison, the Earth is 93 million miles from the sun and orbits it every 365.24 days.
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Bottom line: NASA video discussed the discovery of an immense hydrogen cloud streaming off a Neptune-sized exoplanet 20 light years away.
from EarthSky http://ift.tt/1XMt4bk
About 30 light years away, a Neptune-sized planet is having some of its layers peeled back. Astronomers using NASA’s Hubble Space Telescope have discovered an immense cloud of hydrogen evaporating from a Neptune-sized planet named GJ 436b.
The planet’s atmosphere is evaporating, say scientists, because of extreme irradiation from its parent star — a process that might have been even more intense in the past.
David Ehrenreich of the Observatory of the University of Geneva in Switzerland is the study’s leader. He said:
The parent star, which is a faint red dwarf, was once more active. This means that the planet’s atmosphere evaporated faster during its first billion years of existence. Overall, we estimate that the planet may have lost up to 10 percent of its atmosphere.
GJ 436b is considered to be a “Warm Neptune” because of its size and because it is much closer to its parent star than Neptune is to our own sun. Orbiting at a distance of less than 3 million miles, It whips around the central red dwarf in just 2.6 Earth days. For comparison, the Earth is 93 million miles from the sun and orbits it every 365.24 days.
Enjoying EarthSky? Sign up for our free daily newsletter today!
Bottom line: NASA video discussed the discovery of an immense hydrogen cloud streaming off a Neptune-sized exoplanet 20 light years away.
from EarthSky http://ift.tt/1XMt4bk
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