Newly-published findings have revealed quite the shocking cosmic discovery: an Earth-sized planet that is believed to be covered in volcanoes and rival the likes of the most volcanically active satellite Io.
Due to tidal grip, the daytime side of the planet is likely very hot, and liquid water is unlikely to exist on it. However, analysis has shown that LP 791-18d regularly passes close to LP 791-18c, a much more massive outer planet, while orbiting the star.
"A big question in astrobiology, the field that broadly studies the origins of life on Earth and beyond, is if tectonic or volcanic activity is necessary for life," said study co-author Jessie Christiansen. "In addition to potentially providing an atmosphere, these processes could churn up materials that would otherwise sink down and get trapped in the crust, including those we think are important for life, like carbon."
The gravitational interaction of the planets causes the planet's orbit to stretch into an ellipse, causing its interior to be heated by tidal forces. Tidal heating, in turn, is likely to cause regular volcanic eruptions, similar to what happens to Io and other satellites of the giant planets in the solar system.
The eruptions are likely to emit gases which can create an atmosphere with a pressure suitable for the existence of liquid water on the night side.
The exoplanet was discovered by ground-based telescopes, as well as the Transiting Exoplanet Survey Satellite (TESS) and archived data from the now-defunct Spitzer Space Telescope.
The findings were published Wednesday in the journal Nature.