This may be the closest humans have come to finding another planet that can support life. In a shocking discovery, astronomers have discovered an atmosphere around an Earth-like rocky planet, about 48 light-years away.The planet, called LHS 1140 b, orbits in the habitable zone of its star, meaning it is at the right distance from its star for liquid water to possibly exist on the planet. According to new research published in Science magazine, it has an atmosphere containing helium, and it is also the first rocky planet to have an atmosphere directly discovered.“We’ve already directly detected helium in the atmosphere itself, and this is the first direct detection of any rocky exoplanet, which is really exciting…And then there’s this added bonus of it being in the habitable zone, which is very exciting for astrobiology and habitability and the search for life,” said lead author Colin Cherubim, who recently received his Ph.D.
From Harvard University, for Space.com.
“It feels kind of surreal.”
How is the planet?
The exoplanet, or planet outside our solar system, was discovered in 2017 by a team led by astronomer Jason Dittman, who is now a co-author on this new discovery. “This planet was found 10 years ago, and now we’re saying, ‘OK, it has an atmosphere,'” Dittmann told Space.com. “We’re slowly narrowing the gap and checking these boxes… We found a rocky planet, a planet with the right temperature and now… it’s okay, we’ve finally found a planet with an atmosphere.
“As it orbits a red dwarf star that is smaller and cooler than the Sun, it orbits closer to its star than Earth, maintaining a temperature that keeps the planet in the “Goldilocks zone” where liquid water can exist on its surface. “It also probably has a lot of water in it,” Cherubim said. “If it had some amount of atmosphere that could provide a little bit of greenhouse effect, which we know now, it would very likely have what we consider to be habitable conditions on Earth, conditions that could potentially support liquid water.”
“But is it a second Earth? Although it is certainly not a copy of Earth, this planet is similar to it in two main ways. The first is its general composition: the planet is rocky, likely has an iron core and has an atmosphere. Second, its temperature is just right for liquid water, which is vital for life.
Find Joe
While a few rocky planets have been found in the habitable zone around their star, none of them have had an atmosphere like this.
The discovery of the first exoplanet was confirmed just over 30 years ago. Since then, scientists have discovered more than 6,000 exoplanets and more.
While a few rocky planets have been found in the habitable zone around their star, none of them have had an atmosphere.To prove that this planet has an atmosphere, the team started with a prediction made by the Cherubim during graduate school, using a theoretical model and the suspicion that there must be rocky exoplanets with atmospheres other than Earth. “I went out and did something rather strange and unexpected with this technology normally reserved for observing giant planets, and I used it for a rocky planet, which no one had done before.
Lo and behold, I made this measurement that was actually consistent with my expectations. “It was really nice to close the full loop on the scientific method.”One of the reasons scientists have had difficulty finding such planets with atmospheres is because of their stars. LHS 1140 b orbits the most common type of star, a red dwarf, which is about a third the size of our Sun. This type of star remains active much longer than stars like our Sun.
This activity means that it releases bursts of intense radiation such as solar flares and coronal mass ejections, which can completely strip the atmosphere of the planets it orbits.“This discovery is important because it shows that at least this rocky planet has maintained an atmosphere over billions of years,” Cherubim said. It’s “a powerful, well-intentioned way of saying yes, atmospheres can survive on rocky exoplanets.”There is a possibility that there are gases other than helium in the planet’s atmosphere. But the red dwarf around which this planet orbits is about 6 billion years old, a few billion years older than the age at which its intense radioactivity begins to subside. So, while some helium is still slowly escaping from the planet’s atmosphere over time, the team expects the planet to retain an atmosphere, Dittmann said. After all, even helium found on Earth is slowly escaping from our atmosphere.
Are there foreign residents?
Currently, researchers lack sufficient data to make this guess
When looking at a planet that is rocky, has an atmosphere, and is located in the habitable zone, the question of existing life quickly arises. But currently, researchers lack enough data to make this guess. “I am not claiming that this planet has life,” the Cherubim explained. Additional observations may not be able to confirm habitability or identify any life on the planet, but they could at least help understand planets like these better.As scientists and astronomers continue to search for planets that could be considered “habitable,” this planet checks more boxes than any other before.
