Scientists have discovered a new earth-like exoplanet orbiting a red dwarf planet some 40 light years away from earth. The newly discovered planet orbits the dwarf star in the habitable zone- where water has the potential to exist in liquid form.
An international team of scientists pressed the European Southern Observatory (ESO)’s HARPS instrument at La Silla, Chile, into service, along with other space telescopes from around the world, to zone in on the planet, labelled ‘Super Earth’. The parent star is a red dwarf star called LHS 1140, while the Super-Earth has been named LHS 1140b.
Red dwarf stars are cooler than our own Sun, which is why, even though LHS 1140b is ten times closer to its parent star than the Earth is to the Sun, it receives just half the sunlight from its star as the Earth receives from the Sun. This makes the climate on the planet extremely suitable to harbour life and contain water in its liquid form.
The new discovery has generated sufficient excitement in the astronomical community to want them to explore it further and on a larger scale. According to astronomers, Super Earth LHS 1140b is their best bet to find life beyond the Solar System.
“This is the most exciting exoplanet I’ve seen in the past decade,” Jason Dittmann, a postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics (CfA) and lead author on the paper describing the discovery, said in a statement from CfA. “We could hardly hope for a better target to perform one of the biggest quests in science — searching for evidence of life beyond Earth.”
The new exoplanet is larger and more massive than Earth, and is likely to exhibit much of the same features in its atmosphere as Earth’s. From their observations, astronomers have been able to calculate that the diameter of the new planet is around 1.4 times larger than the Earth’s diameter, which comes up to almost 18 000 kilometres. Its mass is 6.6 times that of Earth’s.
These figures imply that the planet has a much higher density than Earth’s, suggesting that the exoplanet is possibly made of rock with a solid iron centre.
“What’s great about having a density ahead of an atmospheric study is that this density tells you how tightly the planet holds on to its atmosphere (the atmospheric scale height),” according to Dittmann. A higher density also translates into a stronger gravitational force, which makes the discovery all the more exciting.
The team plans to use the Hubble Space Telescope to better study the star and the planet, and to gather data related to its atmosphere. Important features of the atmosphere- such as presence of oxygen, carbon dioxide or methane- could provide vital clues to whether the planet harbours life, or whether it has the ability to.
Hundreds of exoplanets in the habitable zone of their parent stars have been discovered thus far. But regarding the existence of life, it remains to be seen when scientists are able to strike to gold!