Some of the planet’s initial oxygen would be absorbed by this magma ocean, but Schaefer concluded only a tenth would be captured this way. Far more would escape into space, despite GJ 1132b having stronger gravity than Earth. Nevertheless, Schaefer’s modeling raises several scenarios where some might survive, although it found surviving water vapor is much less likely.
"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," Schaefer said in a statement.
"This planet might be the first time we detect oxygen on a rocky planet outside the solar system," said co-author Dr Robin Wordsworth. The possibility increases the incentive to devote scarce time on the next generation of telescopes to observing this world.
The three known planets in the TRAPPIST-1 system, at a similar distance, may be even better prospects for oxygen, since the less energetic molecules in their cooler atmospheres would be less likely to escape.
Studying planets like GJ 1132b may help us understand Venus’ evolution. Astronomers are puzzled as to why Venus has almost no molecular oxygen, despite being thought to have had water that split, with the hydrogen escaping into space. Speculation Venus once supported a liquid ocean has put renewed interest into the topic.