A rare ‘neptune-sized’ planet has been discovered orbiting scorchingly close to its host star – only the fourth planet of its kind found.
Scientists at NASA have uncovered a planet, named TOI-3261 b, outside of our solar system, an exoplanet, using the space telescope TESS (the Transiting Exoplanet Survey Satellite). Further observations were then made using ground-based telescopes from around the world.
The size of the planet has placed it in a category with so few members that it’s dubbed the “hot Neptune desert”, a name given due to their scarcity similar to a deserted landscape. One of the reasons that hot Neptunes are so rare is that it is difficult to retain a thick gaseous atmosphere so close to a star.
The new planet is reportedly similar to our own Neptune in both size and composition, yet it orbits much closer to its star. This means just one year on TOI-3261 b is only 21 hours long, not even a day on Earth.
NASA says the new discovery is the perfect candidate for testing new computer models of planet information.
So far, using different starting points and development scenarios, scientists have determined that both the star and planet system that it’s in is about 6.5 billion years old, with the planet initially starting out much larger than it is now.
Planets can lose their mass over time through various ways. This one was likely due to photoevaporation, when energy from the star causes gas particles to dissipate, and tidal stripping, when the gravitational force from the star strips layers of gas from the planet.
What is left of the planet’s atmosphere intrigues NASA the most, with hopes to probe further into atmospheric analysis to unravel its formation history.
The first ever discovery of one of the now four hot Neptune planets was in 2020, LTT-9779 b. Since then, TOI-849 b and TOI-332 b were found with TOI-3261 b joining the group.
Scientists are currently planning to use infrared observations for two of these planets using the James Webb Space Telescope. This is to hopefully broaden our understanding of these planets’ atmospheres in the coming years.
