Because LHS-1140b is so close, and the star it is orbiting is so dim, it will be comparatively visible. That means that, using telescopes that are currently being built, and even ones that currently exist, it may be possible to get some information about its atmosphere.

“We’re going to try to do it with some telescopes that exist now,” says Dittmann. “We can start chipping away at it with the Hubble Space Telescope and some of the big ground-based telescopes.

“But it’s mainly a study for the future.” He mentions the James Webb Space Telescope, which will be launched in 2018, and the Giant Magellan Telescope, which will be commissioned in 2022, as possible sources of more information.

The telescopes will mainly be looking for oxygen. “That’s the big one that everyone wants to see,” says Dittmann.

That’s because, on Earth, oxygen is produced by life – specifically, by plants, algae, and bacteria that use the sun’s energy to strip carbon from carbon dioxide and release the oxygen. But oxygen is a highly reactive gas, so it doesn’t stay in the atmosphere on its own for very long: It reacts with other things to form compounds. That means that if oxygen is detected in large quantities in a planet’s atmosphere, there must be some chemical process that is making it.

That doesn’t necessarily mean life, says Dartnell. “There are ways of making oxygen in an atmosphere, in the short term, that don’t involve life,” he says.

“What happened on Venus is that the planet got so hot that the seas boiled, and water vapour got high enough into the atmosphere that it started getting split into hydrogen and oxygen by ultraviolet radiation from the sun.”

That built up enough oxygen in the atmosphere to be detectable by telescopes at the time, he said. “But that is basically the planet dying, boiling itself dry with this runaway greenhouse effect.”