On Wednesday, an international team of scientists announced the discovery of two new “super-Earth” planets just 100 light-years away. Both are way bigger than our own planet, and one of them may even be habitable.
According to NASA, super-Earths are a distinct class of exoplanets in the solar system that are more massive than our planet but lighter than the ice giants. They are formed by a combination of gas and rock and can grow up to ten times the size of the Earth’s mass.
The discoveries were made using NASA’s Transiting Exoplanet Survey Satellite (TESS) and the University of Liège’s Search for Habitable Planets Eclipsing Ultra-Cool Stars (SPECULOOS).
According to NASA, both newly discovered planets orbit LP 890-9, a “relatively low activity” red dwarf star with a restricted habitable zone.
The first planet, LP 890-9b or TOI-4306b, was discovered by NASA’s satellite and later verified by SPECULOOS as an exoplanet. With a radius of more than 5,200 miles, it is around 30% larger than our planet and orbits its sun in just 2.7 days.
The most exciting discovery, however, has been a second planet previously unknown to scientists. LP 890-9c, also known as SPECULOOS-2c, is significantly farther away from its star than the first. It is approximately 40% larger than Earth, has a radius of more than 5,400 miles, and takes around three times as long as Earth.
That orbit duration, according to experts, falls within the star’s habitable zone.
“Although this planet orbits very close to its star, at a distance about ten 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,” study co-author Francisco Pozuelos said.
This is due to the planet’s star, LP 890-9, being approximately 6.5 times smaller and roughly half as cool in temperature as our sun, he stated.
“This explains why LP 890-9c, despite being much closer to its star than the Earth is to the Sun, could still have conditions suitable for life,” Pozuelos added.
Researchers will now investigate the planet’s atmosphere to see if it is livable. Based on their findings, it is thought that it could be the second most suitable terrestrial planet for life.
“The discovery of LP 890-9c, therefore, offers a unique opportunity to better understand and constrain the habitability conditions around the smallest and coolest stars in our solar neighborhood,” lead researcher Laetitia Delrez said.