A Neptune-sized Exoplanet is Denser Than Steel. The Result of a Catastrophic Collision?

There’s an odd exoplanet out there posing a challenge to planetary scientists. It’s a hot Neptune denser than steel. The big question is: how did it form? The planet is TOI-1538b and it orbits its parent dwarf star every 1.24 days. It’s classified by planetary scientists as a world in the “Hot Neptune Desert”. That …