An global team of astronomers has found that a little-known exoplanet called K2-18b could be a scaled-up version of Earth, and also discovered the planet has a massive neighbor, K2-18c.
The astronomical discovery was made by researchers from the University of Texas and Montreal, who saw that a neighboring planet of the K2-18b (K2-18c) might also be a second "supernatural", as they call it due to similarities with our planet. While combing through their data, researchers discovered that K2-18b was situated right next to yet another super-earth, a newly discovered exoplanet named K2-18b that scientists believe is also roughly the same mass as Earth.
K2-18 is a red dwarf star in the constellation Leo and K2-18b was discovered in 2015. It's about 2.5 times bigger than Earth, but eight times more massive.
K2-18b even has a neighbouring sister planet, the cleverly named K2-18c, but is unlikely to host life because it is slightly closer to its Sun. Out of this number, fifty are potentially habitable.
One of the more common methods of finding exoplanets is by their transit. It turned out to be another planet much closer to the star.
To do that, Cloutier and his fellow researchers used data from the High Accuracy Radial Velocity Planet Searcher on the European Southern Observatory's 3.6-meter telescope in La Silla Observatory, Chile. They measured radial velocities of stars, which can reveal the existence of planets located around the measured stars.
"Being able to measure the mass and density of K2-18b was tremendous, but to discover a new exoplanet was lucky and equally exciting", said Ryan Cloutier, a PhD student at University of Toronto.
It was while studying those tiny movements of the star that something interesting was discovered: the star wasn't wobbling as it should if there was just one planet.
"So you go, what the heck's that thing at nine days?" Kepler was unable to spot it as it was on an inclined plane and didn't pass in front of the star.
And the exciting discovery doesn't end there.
"The most thrilling part was that first hint that there might be something there", said Cloutier.
René Doyon, Cloutier's co-supervisor and a co-author of the paper published Tuesday in the journal said the next step will be to determine the atmosphere of K2-18b, since it's the most promising candidate for sustaining life.
"(The James Webb Space Telescope) is going to vastly expand that parameter space, expand the number of planets that we can actually make these measurements for, and then I'll be able to tell you something interesting about those exoplanet atmospheres". "It's in the habitable zone, so it's very unique".
The James Webb Space Telescope is supposed to be a successor to the Hubble Space Telescope, and just recently it finished its test that took place in a frigidly cold chamber.