Extreme heating and atmospheric secrets of the eccentric giant planet HD 80606 b

Star system: HD 80606 | Distance from the Sun: 215 light years

Astronomers have peeked into the atmosphere of HD 80606 b, one of the most unusual gas giants known due to its incredibly stretched, eccentric orbit. As the planet swings extremely close to its parent star—reaching a distance of just 0.03 AU, much closer than Mercury is to our Sun—it experiences rapid, intense heating. Using high-resolution spectroscopy from the Keck Observatory, researchers looked for signs of chemical changes during this thermal spike. 

The study found tentative evidence of methane and carbon monoxide in the planet's atmosphere. These results align with recent space-based observations, suggesting that despite the hellish heat near its star, the planet's atmosphere shows weak absorption features rather than a strong thermal inversion, providing a clearer picture of how these extreme worlds react to sudden temperature swings.

Scientific study

Limits on the Post-eclipse Emission Spectrum of HD 80606 b From High-Resolution Spectroscopy (external link)