Wednesday, another red dwarf star is making headlines with the announcement of a "super earth" found orbiting around the small red star LHS 1140. Although red dwarfs are much smaller and cooler than the sun, the LHS 1140b exoplanet makes up for it by orbiting ten times closer to its parent star than Earth orbits the sun.
Over the previous year, researchers have found nearby exoplanets that could potentially support life, like Proxima b and the seven TRAPPIST-1 planets.
'We could hardly hope for a better target to perform one of the biggest quests in science - searching for evidence of life beyond Earth'. But just like Earth, this planet sits in the coveted habitable zone, the region around a star where temperatures are just right for liquid water to pool on a planet's surface. Meaning, one side of the planet always faces the star while the other faces away.
Since the star it orbits is quite small and relatively close to us, it may be possible for current telescopes and those now under construction to determine if the planet has an atmosphere.
The astronomers estimate the age of the planet to be at least five billion years and that it is 1.4 times larger and seven times more dense than Earth.
Anyway, we know that there is a planet around the star LHS 1140, named according to convention as LHS 1140b.
Still, Dittmann thinks that the TRAPPIST-1 system, also located roughly 40 light years away, stands out as a particularly intriguing.
The star that LHS 1140b orbits is both small and faint.
"Given its large surface gravity and cool insolation, the planet may have retained its atmosphere despite the greater luminosity (compared to the present-day) of its host star in its youth", the study authors wrote. Effectively, the star and the planet orbit around a mutual centre, which falls somewhere inside the star for most planets.
The planet's orbit is 10 times closer to its star than the Earth is to the Sun, according to early measurements. "But we know that things can live at very high pressures at the bottom of the ocean, and we know of lots of bacteria that can survive all sorts of insane environments, so I think it's not infeasible to imagine some form of life being ok with living on a super-Earth". All the same, "a few years ago we didn't know about any such planets, and now we know about several", says Ian Crossfield of the University of California, Santa Cruz, who was not involved in the latest discovery.
In the future, they want to use HARPS to continue observing the star and see if there are more planets around it. The new planet, designated LHS 1140b, has a diameter of around 11,000 miles.
When red dwarf stars are young, they are known to emit radiation that can be damaging for the atmospheres of the planets that orbit them. One of the key similarities between it and our own orb that we call home is that it "receives similar amounts of energy from its star that Earth does from the Sun, which means it may have liquid water on its surface". Three of the planets are in the Goldilocks zone, though all of the TRAPPIST-1 planets are believed to be rocky.
Researchers believe it may be one of the best candidates for a closer look in the future by the James Webb Space Telescope, which NASA will launch in 2018.
Dittman calls LHS 1140b the most exciting exoplanet he's seen in the past decade.
"We are very excited by this discovery". Once it's completed, JWT will be the most powerful space-based telescope ever deployed - it will be used to peer into the atmospheres of all of these planets and more. They want to confirm the existence of the planet's atmosphere and find out if it has molecular oxygen or water, and if it's similar to Earth.