According to Science Alert, this is the planet TOI-332b, orbiting an orange dwarf star located 727 light-years from our Earth.
Measurements based on the planet’s effects on its parent star’s light each time it passes have allowed a group of scientists, led by astronomer Ares Osborn from the University of Warwick in the UK, to calculate that it is a world with a radius 3.2 times that of Earth, orbiting its parent star every 18.72 hours.
Graphic depicting a giant planet being stripped of its atmosphere – Image: SCIENCE ALERT
What’s more interesting is that this planet is situated in an area called the “Desert of Hot Neptunes,” a mysterious region surrounding some stars, where Neptune-sized planets are notably absent.
TOI-332b is entirely baffling to scientists. Despite being in the Desert of Hot Neptunes, it has a size nearly comparable to that of a Hot Neptune – a planet with a radius 3.88 times that of Earth.
However, it is 57.2 times heavier than our world, while Hot Neptunes are only about 17.15 times Earth’s mass.
This size and weight make it a world with an astonishing density of 9.6 g/cm³, heavier than a solid iron ball of the same size!
Based on observational data modeling, scientists believe it’s a giant iron core, densely packed, with a rocky layer and a thin gaseous envelope containing hydrogen and helium, even though it should have been a gas giant like Jupiter when formed in this region.
For a world so close to its star, the process of photonic heating, causing the atmosphere to slowly leak away into space, is possible. However, it cannot explain the transformation of a gas giant into a solid iron lump.
There are two chilling scenarios about how this planet became a “bone-dry” state, i.e., a barren core like it is now.
The first scenario suggests it could have formed at a more distant location, then moved closer to its parent star as it evolved. Gradual heating due to the narrowing distance and internal changes could have stripped away its atmosphere.
Another possibility is that it fell victim to another planet. A catastrophic collision could have blown away its entire atmosphere.
The third, less likely, scenario is that it was born in this peculiar “bone-dry” state, unable to accumulate an atmosphere from the beginning.
Regardless, TOI-332b remains an enigmatic and bizarre world that scientists hope to study more closely with advanced observation tools after this initial discovery.