With so many planets out there, the observational exoplanetary-science community is fiercely focused on identifying the most promising candidates for the next phase of their search, for the select few that will be first in line to command time on advanced new spaceborne and larger ground-based telescopes, scheduled to come online in the next few years.
LHS1140b has a mass that's comparable with our planet, a surface that's possibly rocky because of its high density, and a temperature that's neither too hot nor too cold because it's orbiting its star at just the right distance for the possibility of liquid water to be present.
Using ESO's HARPS instrument at La Silla, and other telescopes around the world, an global team of astronomers discovered a "super-Earth" orbiting in the habitable zone around the faint star LHS 1140.
The finding was detailed in a study, featured April 19 in the journal Nature.
Dittmann, a lead author of the study who is now working with postdoc Sarah Ballard at the MIT Kavli Institute for Astrophysics and Space Research, will be joining the group of MIT Professor Sara Seager in July as the inaugural Heising-Simons Pegasi B Fellow. This world is a little larger and much more massive than the Earth and has likely retained most of its atmosphere.
In a new study scientist suggests most habitable planets in the universe are dominated by oceans and the extent could be more than 90 percent. Because red dwarfs are known to emit harmful radiation that can damage planets orbiting them, it's possible that while LHS 1140b might have had liquid water within its lifetime, continuous bombardment of radiation from its host star might have stripped the planet of all that water. However, although it sits 10 times closer to its star than Earth to our sun, it only receives about half the warmth our planet enjoys, making for an uncomfortably chilly world. This planet, designated LHS 1140 b, orbits its star every 25 days. "We could hardly hope for a better target to perform one of the biggest quests in science - searching for evidence of life beyond Earth". LHS 1140b's size has astronomers convinced it could have once been oozing with magma. This seething ocean of lava could feed steam into the atmosphere long after the star has calmed to its current, steady glow, replenishing the planet with water.
To spot the new exoplanet, researchers initially used the transit method, looking at the light from its star and trying to measure subtle dips in its intensity, typically produced by a passing planet.
The astronomers estimate the age of the planet to be at least five billion years.
This super-Earth may be the best candidate yet for future observations to study and characterise its atmosphere, if one exists. Sound familiar? The TRAPPIST-1 system also orbits an M-Dwarf, but here's why this discovery could be even more explosive. "Jason brings extensive expertise in exoplanet discovery that will be a huge asset to the MIT TESS team", Seager says.
There are a lot more questions than answers at this time, of course.
In particular, observations coming up soon with the NASA/ESA Hubble Space Telescope will be able to assess exactly how much high-energy radiation is showered upon LHS 1140b, so that its capacity to support life can be further constrained. Future technologies such as the upcoming Extremely Large Telescope and the James Webb Telescope should be able to observe alien atmospheres at a level of detail that will be nothing less than mind-blowing.