NASA's space agency has discovered a mysterious "super-Earth" planet that may be emitting a repeating signal from a distance of 154 light-years. The planet, named TOI-1846 b, is almost twice the size of Earth and four times more massive, writes UNN with reference to the Daily Mail.
Details
The planet orbits a small, cold red "dwarf" every four days and causes a strange, repeating drop in the star's light. This is the signal that first caught the attention of scientists when NASA's TESS space telescope observed a dimming pattern in March of each year.
Now, a team of scientists has confirmed that TOI-1846 b falls into the so-called "radius gap" – a rare category between small, rocky planets like Earth and larger, gas-rich planets like Neptune.
Despite an estimated surface temperature of 600°F, researchers say the planet could still contain water. It is believed to have a solid rocky core, a dense layer of ice, and possibly even a shallow ocean or a thin atmosphere.
Lead researcher at the Oukaimeden Observatory in Morocco, Abderrahmane Soubkiou, said: "We confirmed the presence of TOI-1846 b using TESS data and multi-color ground-based photometric data, high-resolution images, and spectroscopic observations."
Their measurements also showed that the planet orbits its star in just under four days, remaining in an orbit much closer to its sun than Mercury in our Solar System.
The host star is a "red dwarf," approximately 40% smaller in size and mass than our Sun, glowing at a temperature of about 6000°F.
Since red dwarfs are smaller and dimmer, planets must orbit close to the star to receive heat, which also makes it easier for telescopes to detect them when they pass in front of the star.
The TESS telescope, launched in 2018, has recorded over 7600 such transit events and confirmed the existence of over 630 planets to date.
The telescope's four highly sensitive cameras scan the sky every 30 minutes, making it ideal for detecting shallow dips in light, similar to those observed in TOI-1846 b.
The newly discovered planet is likely also tidally locked, meaning one side always faces its star while the other remains in darkness. This temperature contrast could allow water to persist in colder regions, depending on how heat moves through the atmosphere.
NASA scientists hope that the James Webb Space Telescope will soon target TOI-1846 b to study its atmosphere using infrared light.
Under favorable conditions, Webb will be able to detect signs of water vapor, methane, carbon dioxide, or other gases.
Since red dwarfs make up about 75% of all stars in the Milky Way, studying planets like TOI-1846 b could reveal how many more potentially habitable worlds might be hiding in our galaxy.
Addition
The new HWO space telescope, to be unveiled in 2025, is designed to search for and characterize potentially habitable exoplanets. Its main goal is to detect liquid water on the surface of at least 25 planets.