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A distant planet may be in its second atmosphere, finds NASA’s Hubble. Scientists using NASA’s Hubble Space Telescope have found evidence that a planet orbiting a distant star may have lost its atmosphere, but gained another due to volcanic activity.

The planet, GJ 1132 b, is believed to have originated as a gaseous world with a thick layer of hydrogen in the atmosphere. This so-called “subneptune” is believed to have rapidly lost its initial hydrogen-helium atmosphere due to intense radiation from the hot young star that orbits it, starting at several times the diameter of Earth.

Before long, such a planet would erode into a bare core the size of Earth. That’s when things got interesting. This is an artist’s impression of the rocky Earth-size exoplanet GJ 1132b, located 41 light-years away around a red dwarf star.

Scientists using NASA’s Hubble Space Telescope have found evidence that the planet has lost its original atmosphere but gained a second, a toxic mix of hydrogen, methane, and hydrogen cyanide. Hubble detected “fingerprints” of these gases as light from the parent star filtered through the exoplanet’s atmosphere.

The planet is too far away and too dark to be imaged by Hubble. It shows what astronomers believe in this distant world. Beneath the planet’s hazy and hazy atmosphere, there may be a thin layer only a few hundred feet thick.

Molten lava continues to seep through volcanic cracks below the surface. Gases seeping through these cracks appear to continually fill the atmosphere, which would otherwise be washed away by scorching radiation from the planet’s closest star. The gravitational pull of another planet in the system is likely to make GJ 1132b’s surface look like a broken eggshell.

This is the first time that a “secondary atmosphere” has been detected on a planet outside our solar system. To the astronomers’ surprise, Hubble observed an atmosphere that, according to his theory, is a “secondary atmosphere” that now exists.

Based on a combination of evidence from direct observation and inference via computer modeling, the team reports that the atmosphere consists of molecular hydrogen, hydrogen cyanide, methane, and also contains an aerosol haze. Modeling suggests that aerosol haze is based on photochemically produced hydrocarbons, similar to haze on Earth.

Scientists interpret the atmospheric hydrogen present in GJ 1132 b as hydrogen from the original atmosphere that was absorbed by the planet’s molten magma mantle and is now slowly released through volcanic processes to form a new atmosphere. It is believed that the atmosphere we see today is constantly being replenished to balance the hydrogen going into space.

Study co-author Raisa Estrella, from NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, said: This is very exciting because we believe that the atmosphere that we see now has regenerated, so there may be a secondary environment.

We previously thought that these highly irradiated planets could be very boring because we thought they had lost their atmosphere. But we looked at the current observations of this planet with Hubble and said, ‘Oh no, there is an atmosphere there.’

The rocky exoplanet GJ 1132b, similar in size and density to Earth, has a hazy atmosphere composed of volcanic gases. Scientists say that GJ 1132b, which orbits a red dwarf star about 41 light-years away, has some characteristics in common with worlds in our own solar system, as well as big differences.

Its hazy appearance can be compared to that of Titan, Saturn’s largest moon, the only moon in the Solar System with a substantial atmosphere, although Titan is much cooler. Our own Earth may have had such a weak presence in its history, although unlike Earth, the new planet is too hot to be habitable.

And it is likely that GJ 1132 b had a “secondary atmosphere”, created by volcanic activity, before its hydrogen-helium atmosphere was removed by radiation from its star. The findings could have implications for other exoplanets, planets beyond our solar system.

“How many terrestrial planets do not start out as terrestrial? Some may start out as subneptunes and become terrestrial through a mechanism that photoevaporates the primary atmosphere. It works early in life, when the star is at its hottest,” said JPL lead author. , Mark Swain.

“So the star cools down and the planet just stays there. So you have this mechanism where you can cook the atmosphere in the first 100 million years, and then things calm down. once you can. ” Located about 41 light years from Earth, GJ 1132b has some similarities to Earth in some ways, but in some ways it is very different.

The density of both, the same size and the same age, is about 4.5 billion years. Both started with a predominantly hydrogen atmosphere and both were hot before cooling down. The team’s work also shows that GJ 1132b and the Earth’s surface have similar atmospheric pressure.

But the formation history of the planets varies. Earth is not believed to have a living subneptune nucleus. And Earth orbits at a comfortable distance from our Sun. GJ 1132 b is so close to its red dwarf star that it completes one orbit around its host star once every day and a half.

This extreme proximity blocks GJ 1132 b in the form of a tide, showing the same face to its star at all times, just as our Moon maintains a hemisphere permanently in front of Earth. The question is, what keeps the mantle warm enough to remain liquid and the volcano of energy? Swain asked.

This system is special because it has the opportunity for a lot of tidal heating. Tidal heating is a phenomenon that occurs, through friction, when the energy from the orbit and rotation of a planet dissipates as heat within the planet. GJ 1132 b is in an elliptical orbit and the tidal forces acting on it are strongest when it is closer to or further from its host star.

At least one other planet in the host star system also exerts a gravitational pull on the planet. Scientists using NASA’s Hubble Space Telescope have found evidence that a planet orbiting a distant star may have lost its atmosphere, but gained another due to volcanic activity.

The planet, GJ 1132 b, is believed to have originated as a gaseous world with a thick layer of hydrogen in the atmosphere. This so-called “subneptune” is believed to have rapidly lost its initial hydrogen-helium atmosphere due to intense radiation from the hot young star that orbits it, starting at several times the diameter of Earth.

Before long, such a planet would erode into a bare core the size of Earth. That’s when things got interesting. The result is that the planet is compressed or stretched through this gravitational “pump”. This warming of the tides keeps the mantle liquid for a long time.

A close example in our own solar system is Jupiter’s moon Io, which has sustained volcanic activity due to tidal interactions between Jupiter and neighboring Jovian moons. By looking at the warm interior of GJ 1132b, the team believes that the coldest upper crust on the planet is extremely thin, perhaps only hundreds of feet thick.

It is too weak to support something like a volcanic mountain. Its flat terrain can also crack like an eggshell due to tides. Hydrogen and other gases can escape through these cracks. NASA’s upcoming James Webb Space Telescope has the ability to see this exoplanet. Webb’s infrared vision could allow scientists to see the planet’s surface.

If there are pools of magma or volcanoes, those areas will be hotter, Swain explained. “It would generate more emissions, so they would potentially be looking at actual geological activity, which is exciting! The team’s findings will be published in an upcoming issue of The Astronomical Journal.

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