A planet 48 light-years away has the three key ingredients scientists are looking for: rock, an atmosphere and the right temperature. Could it have life?
This may be the closest humans have ever come to finding another planet that can support life. Astronomers have made a shocking discovery, discovering an atmosphere around a rocky Earth-like planet about 48 light-years from Earth.The planet, called LHS 1140 b, is orbiting within the habitable zone around its star, meaning it is just the right distance from the star for the possibility of liquid water on the planet. It has helium in its atmosphere and is the first rocky planet to have its atmosphere directly detected, according to new research published in the journal Science.“We actually directly detected the presence of helium in the atmosphere, which is the first direct detection of any rocky exoplanet, which is really exciting… and there’s the added bonus that it’s in the habitable zone, which is very exciting for astrobiology and habitability and the search for life,” said lead author Collin Cherubim, who recently earned his Ph.D. a professor from Harvard University told Space.com. “It feels a little surreal.”
What is this planet like?
looking for an atmosphere
While a few rocky planets have been found in the habitable zone of their stars, none have an atmosphere like this.
More than thirty years ago, the discovery of the first exoplanet was confirmed. Since then, scientists have discovered more than 6,000 exoplanets. While a few rocky planets have been found in the habitable zones of their stars, none have atmospheres.To prove that the planet had an atmosphere, the team used theoretical models and suspicion, starting with predictions Cherubin made while a graduate student that there must be rocky exoplanets with atmospheres besides Earth. “I went out and did something very unexpected and strange, using this technique that is normally used to look at giant planets, I used it to look at rocky planets, which no one had done before. Lo and behold, the measurements I made actually agreed with my predictions. It’s really nice to close the whole loop on the scientific method,” he said.One of the reasons scientists have such a hard time finding such planets with atmospheres is their stars. LHS 1140 b orbits a red dwarf, the most common type of star, which is about one-third the size of the Sun. Stars of this type remain active much longer than stars like the Sun. This activity means it emits extreme radiation such as solar flares and coronal mass ejections that can completely strip the atmosphere of a planet orbiting it.“This discovery is significant because it shows that at least this rocky planet has retained an atmosphere for billions of years,” Cherubin said. It’s “a sincere, powerful way to show that atmospheres can survive on rocky exoplanets.”There may be other gases besides helium in planetary atmospheres. But the red dwarf the planet orbits is about 6 billion years old, billions of years before its extreme radiation activity begins to subside. Although some helium is still slowly escaping the planet’s atmosphere over time, the team expects the planet to retain its atmosphere, Dittman said. After all, even Earth’s helium is slowly escaping our atmosphere.
Are there alien inhabitants?
Currently, researchers lack sufficient data to make this conjecture
When looking at a planet that is rocky, has an atmosphere, and is in the habitable zone, the question of whether life could exist quickly arises. But currently, researchers lack enough data to make this conjecture. “I am not saying there is life on this planet,” the cherubim made clear. Further observations may not confirm the planet’s habitability or identify any life, but they could at least help better understand such a planet.As scientists and astronomers continue to search for planets that can be considered “habitable,” this planet is under more scrutiny than any before.
