Could ‘Proxima b’ Be Second Earth? Newly Discovered Planet May Have Breathable Atmosphere
Proxima b's discovery has been announced just a few weeks before, however the planet has been well studied since more than a century. Orbiting the Proxima Centauri, our nearest star beyond the Sun, Proxima b is possible the most habitable planet near Earth, as per reports. NASA Astro-biologists have been crunching all the data available about the rocky planet to figure out how likely it is to be habitable.
A strange thing about the Proxima b though is nobody has actually physically seen it. Astronomer believe it's there as they've seen the Proxima b gravity tugged on and "wiggle" Proxima Centauri, the red dwarf star that it orbits around. No telescopes in space or on ground can directly photograph the planet. Recently Russian billionaire Yuri Milner and Stephen Hawking announced a plan to send probes in search of life to Proxima b.
What do scientists say?
Proxima b orbits around Proxima Centauri in the Goldilocks-like habitable zone, this means that the strength of light is just right there to melt water. But being just 4 million miles away from its Sun, the distance comes with a troublesome consequence. Astronomers believe that Proxima b is tidally locked to its Sun.This will mean that one side of Proxima b always faces its star: always in permanent daylight while the other side is trapped in an endless cold night.
Two researchers at Harvard believe that NASA's James Webb Space Telescope (JWST) that is scheduled to launch in 2018, could find this out by merely sampling the star system's light. "It would take only a day's observing time," Avi Loeb, who is an astrophysicist at Harvard University, told Business Insider. "If Proxima b does really have an atmosphere", says Loeb, "it'd not only circulate warmth from the day side to night side of the planet, but it'd also prevent the planet's water from boiling off into the space."
He believes that the trick to rule out an atmosphere is to focus on using infrared light - the same "color" that shows warm but invisible light that our bodies do constantly emit. When a rocky planet gets warmed up by a star, it does absorb the sunlight and re-emits it in the form of infrared light. Rocky planets emit a different kind of infrared light than that given off by stars like Proxima Centauri.
And luckily, it just so happens that NASA's 'James Webb Space Telescope' has been specially designed to observe this infrared light. Hence, instead of trying to find a tiny planet in a Cluster of galaxies, JWST may only have to look for specific wavelengths of infrared light.
Loeb and Laura Kreidberg, a Harvard astronomer who studies exoplanet atmospheres, believe that if their observation reveals that the dark side of Proxima b isn't as cold as it's supposed to be, it'd mean that an atmosphere is hugging the planet redistributing warmth to the night side. If not, the Proxima b may be another bare and lifeless rock.
"With the light that we detect, we may ask if this world does look like a bare rock. And if it doesn't, there might be a possibility of an atmosphere, there might be an ocean as well, which life requires," said Loeb.