A hot and rocky planet that is just 39 light-years away from Earth may potentially contain an oxygen atmosphere, the first ever found in an exoplanet outside the solar system, a new study suggests.
In November last year, Tech Times reported the discovery of distant planet GJ 1132b, which piqued the interests of scientists because it is the closest exoplanet to Earth.
What they found most fascinating was that planet GJ 1132b has an atmosphere, despite being baked to 450 degrees Fahrenheit (232 degrees Celsius). In fact, its atmosphere is similar to that of Venus.
Now, in a new report, scientists from Harvard-Smithsonian Center for Astrophysics investigate what would happen to the exoplanet over time if it initially possessed a steam, water-rich atmosphere. Details of the research are published [PDF] in The Astrophysical Journal.
'Baked And Sterilized'
Planet GJ 1132b, which revolves around its star at about 1.4 million miles (2.25 kilometers) away, is flooded with ultraviolet light.
The UV light separates water molecules into elements, oxygen and hydrogen, that can be lost in space.
However, since hydrogen is lighter than oxygen, it escapes faster, scientists say. That leaves oxygen to linger behind.
Laura Schaefer, an astronomer from Harvard and lead author of the report, says that on planets that are much cooler, oxygen could be a clue to the planet's habitability and the possiblity of alien life.
But on hot exoplanets such as GJ 1132b, detecting oxygen may be a sign that the planet is being "baked and sterilized," says Schaefer.
Because water vapor is a greenhouse gas, the exoplanet would experience a strong greenhouse effect that amplifies its host star's already intense heat.
The surface of the exoplanet could stay molten for millions of years as a result.
First-Ever Rocky Planet With Oxygen?
According to Schaefer and colleagues, a magma ocean on the exoplanet would potentially interact with its atmosphere and absorb some of the oxygen.
A model that researchers created reveals that only one-tenth of the oxygen will be absorbed, while the remaining oxygen will escape into space. Some oxygen might linger.
Robin Wordsworth, Schaefer's co-author, says planet GJ 1132b may represent the first time scientists detect oxygen on a rocky planet outside our solar system.
If oxygen does linger and cling to planet GJ 1132b, telescopes such as the James Webb Space Telescope and the Giant Magellan Telescope may be able to detect the oxygen and analyze it.
Why The Findings Are Important
Researchers say the magma ocean model could help in unraveling the mystery of how Venus evolved.
This second planet to the sun may have had Earth-like amounts of water at the beginning, which could have been taken apart by sunlight. However, Venus shows no signs of lingering oxygen.
Furthermore, the magma ocean model may also help provide insights into other hot and rocky exoplanets, scientists say.
