Astronomers Found Something Strange In Giant “Forbidden” Planet Nearly the Size of Its Star

Astronomers used JWST to reobserve TOI 5205b, a Jupiter-sized gas giant orbiting a small red dwarf.

The planet’s atmosphere appears to contain fewer heavy elements than expected, or lower metallicity, for a gas giant.

That unusual chemistry makes TOI 5205b difficult to explain with current planet-formation models.

The findings, published in The Astronomical Journal, could prompt revisions to how giant planets grow around low-mass stars.