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A newly discovered planet 40% larger than Earth may be suitable for life

By Dustin Jones

Published September 7, 2022 at 12:07 PM EDT

The telescopes of the SPECULOOS Southern Observatory in the Atacama Desert, Chile. The telescopes were used to confirm and characterize a new planet discovered by NASA, which led to the discovery of another nearby planet.

An international team of scientists says it has discovered two new "super-Earth" type planets about 100 light-years away, one of which may be suitable for life.

Unlike any of the planets in our solar system, the nearly 1,600 known super-Earths are larger than Earth, but lighter than icy planets like Uranus and Neptune.

Researchers at Belgium's University of Liège announced Wednesday that they found another one while using Earth-based telescopes to confirm the existence of a different planet initially discovered by a NASA satellite in the same solar system.

NASA's satellite found planet LP 890-9b, which is about 30% larger than Earth and orbits its sun in just 2.7 days. ULiège researchers used their SPECULOOS (Search for habitable Planets EClipsing ULtra-cOOl Stars) telescopes in Chile and Spain to take a closer look at the planet with high-precision cameras.

That's when the stargazers discovered another planet, LP 890-9c (renamed SPECULOOS-2c by the ULiège researchers), which is 40% larger than Earth and takes 8.5 days to orbit its sun.

Francisco Pozuelos, a researcher at the Institute of Astrophysics of Andalusia and one of the main co-authors of the paper, said in a news release that the planet could be suitable to life despite being a mere 3.7 million miles from its sun. Earth, by comparison, is located over 93 million miles away from our sun.

"Although this planet orbits very close to its star, at a distance about 10 times shorter than that of Mercury around our Sun, the amount of stellar irradiation it receives is still low, and could allow the presence of liquid water on the planet's surface, provided it has a sufficient atmosphere," Pozuelos said. "This is because the star LP 890-9 is about 6.5 times smaller than the Sun and has a surface temperature half that of our star."

NASA's Transiting Exoplanet Survey Satellite (TESS) searches for exoplanets orbiting nearby stars by monitoring light levels of thousands of stars. New planets are discovered when a planet passes in front of one of those stars, causing the light being monitored to dim.

ULiège scientists then follow up NASA's findings with ground-based telescopes to confirm and characterize the planets.