Astronomers Discover an Ocean-Covered “Super-Earth” Exoplanet

Astronomers Discover an Ocean-Covered Exoplanet Named TOI-1452 b

Artistic representation of the surface of TOI-1452 b, which may be a planet entirely covered by liquid water. (Photo: Benoit Gougeon/Université de Montréal)

Science-fiction writers have long dreamed of waterworlds—planets covered in endless ocean. Scientists, too, have postulated that these planets exist. Finding and verifying candidates, however, is elusive. The nearby exoplanet named TOI-1452 b may be the most promising of possibilities discovered. In The Astronomical Journal, scientists say its mass indicates that the surface of the exoplanet may be covered in a layer of liquid ocean.

TOI-1452 b is an exoplanet about 100 light-years from Earth, which is relatively quite close to our planet. It was discovered by NASA's Transiting Exoplanet Survey Satellite (TESS). The system watches stars and detects tiny blips in their shining lights. These blips are indicative of exoplanets passing in between the light source and the satellite. TOI-1452 b was detected in a short 11-day orbit around two small, dim red dwarfs. By calculating the fluctuations in the starlight, scientists could estimate that the exoplanet is 1.672 times the size of our own, known as a super-Earth size.

Studying the light's variations also gave insight into gravitational twitches in the orbit which reveal a body's mass. TOI-1452 b is 4.82 times Earth's mass. This suggests, according to researchers who further investigated the exoplanet at the University of Montreal, a density similar to Earth's. Due to its larger mass, this means the exoplanet is composed of a lighter material, such as water, rather than rock. It seems 30% of the planet may, in fact, be water. For perspective, water accounts for only one percent of Earth's mass.

While scientists have not yet been able to confirm that the exoplanet is covered in ocean water, they hope the incredible James Webb Space Telescope (JWST) will be able to turn its eyes towards the neighboring celestial body soon. The JWST will be able to gaze into the atmosphere of TOI-1452 b. “Our observations with the Webb Telescope will be essential to better understanding TOI-1452b,” astronomer René Doyon of the University of Montreal said in a statement. “As soon as we can, we will book time on Webb to observe this strange and wonderful world.”