The search for Earth’s twin just got a little closer as astronomers recently presented findings regarding a potential icy or watery “super-Earth” called LHS 1140 b, which is located approximately 49 light-years from Earth and whose radius is approximately 1.7 times our planet, along with orbiting within its star’s habitable zone. What makes this finding unique is LHS 1140 b was previously hypothesized to be a mini-Neptune and astronomers speculate could be completely covered in either ice or water.
The findings were recently accepted to The Astrophysical Journal Letters and hold the potential to help astronomers better understand the formation and evolution of exoplanets, and specifically Earth-sized exoplanets within their star’s habitable zone.
Artistic depiction showcasing the potential types of exoplanet that LHS 1140 b could be, either an ice world or an ocean world, with a radius 1.7 times that of Earth. (Credit: Benoit Gougeon, Université de Montréal)
For the discovery, the researchers analyzed data obtained from NASA’s James Webb Space Telescope (JWST), NASA’s Transiting Exoplanet Survey Satellite (TESS), NASA’s Hubble Space Telescope, and NASA’s Spitzer Space Telescope to challenge initial findings that LHS 1140 b was a mini-Neptune. Additionally, with LHS 1140 b having been confirmed to orbit within its star’s habitable zone, this puts LHS 1140 b in a small number of exoplanets that could potentially be considered “Earth-like”, with the potential for it possessing an atmosphere and a liquid ocean.
“Of all currently known temperate exoplanets, LHS 1140 b could well be our best bet to one day indirectly confirm liquid water on the surface of an alien world beyond our Solar System,” said Charles Cadieux, who is a PhD student at the Université de Montréal and lead author of the study. “This would be a major milestone in the search for potentially habitable exoplanets.”
Given the large uncertainty pertaining to LHS 1140 b’s atmospheric and oceanic composition, the researchers emphasize the importance of using JWST for future observations, specifically pertaining to the identification of carbon dioxide within the exoplanet’s atmosphere.
How will LHS 1140 b help astronomers better understand exoplanets in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: NASA, arXiv, EurekAlert!