Scientists discover core of bizarre, Neptune-sized dead planet - Axios

Artist's impression of an exoplanet. Photo: University of Warwick/Mark Garlick

For the first time, scientists have found the core of a dead planet orbiting a star 730 light-years from Earth.

Why it matters: Our solar system only has a few types of planets by comparison to the diversity of worlds out there orbiting other stars. Finding this bizarre world adds to that tapestry — and opens up new avenues for discovery.

Details: A study about the newfound planet — named TOI 849 b — reveals the odd, Neptune-sized world orbits its star once every 18 hours and its surface temperature clocks in at an extreme 2,732°F.

"The planet is strangely close to its star, considering its mass," David Armstrong, one of the authors of the new Nature study said in a statement.
The planet's strange composition is what gave scientists the hint that the world is likely the core of what could have been a much larger gas giant.
The authors of the study found that TOI 849 b has only a small amount of hydrogen and helium and it's incredibly dense at 40 times heavier than the Earth with a radius 3.4 times that of our planet.
According to current models of planetary formation, a planet that massive would have sucked up much more helium and hydrogen than is present now, the study says.

The intrigue: The scientists are confident this world is a dead core of a planet, but they're less sure about how it came to be.

The paper's authors suggest the planet may have once been like Jupiter but lost its atmosphere through a possible collision with another world or tidal forces that disrupted the planet due to its close proximity to its star.
It's also possible at least some of the planet's atmosphere evaporated because of its close-in orbit.
The alien world might also represent a "failed" gas planet where the gas that usually would have been slurped up by the core wasn't available during planet formation.

Let's block ads! (Why?)