SEP 03, 2016

Exoplanet Resembling Venus Could Still Have Oxygen in its Atmosphere

WRITTEN BY: Anthony Bouchard

Scientists have had their eyes on an exoplanet dubbed Gj 1132b that was discovered last year and seems to resemble Venus pretty closely. About 39 light-years away, it’s not so far away that we can’t study it, but it’s still far enough away that it’s difficult to draw conclusions to our many questions about it.
 

 Image Credit: CFA/Dana Berry/Skyworks Digital

The qualities of this exoplanet are definitely very different than Venus in many ways, but similar in others. For example, the chemical makeup is similar, but it orbits its parent star, a red dwarf, at only about 1.4 million miles away, which is significantly closer than Earth or Venus from our Sun. This makes Gj 1132b a hot place.
 
But is there any oxygen on it? That’s the million-dollar question, and in a paper published on arXiv, scientists tackle the many scenarios for how the planet could still have oxygen in its atmosphere by making several predictions that can be tested in the future.
 
The close relativity to its star means that the planet gets bombarded with UV light, and this means water can’t possibly exist. Because of the heat, which can reach a scorching 450º Fahrenheit, astronomers agree that life on Gj 1132b is extremely unlikely.
 
"On cooler planets, oxygen could be a sign of alien life and habitability. But on a hot planet like GJ 1132b, it's a sign of the exact opposite - a planet that's being baked and sterilized," said lead author Laura Schaefer.
 
If there ever was any water, then the UV light would have ripped those H2O molecules apart into lone hydrogen and oxygen molecules. The excited hydrogen atoms are going to be the quickest to escape the planet’s atmosphere due to their nature, so scientists think some oxygen could still exist there.

"This planet might be the first time we detect oxygen on a rocky planet outside the solar system," said co-author Robin Wordsworth.

One of the things that might play a role are the possible molten magma oceans that could be a result of the close proximity to its host star. It’s said that the magma ocean could absorb up to 10% of the planet’s oxygen resources, while the other 90% gets blasted into space.
 
There is no clear-cut answers to this question yet, but if the theory is true, then further observations with other equipment designed for this sort of thing, like the upcoming James Webb Space Telescope, could provide clue.
 
Finding out more about Gj 1132b could also help us to learn more about how our very own planet, Venus, was formed.
 
Source: EurekAlert