Detailed analysis of WASP-31 b's atmosphere and orbital alignment

Star system: WASP 31 | Distance from the Sun: 1266 light years

A new study using the ESPRESSO spectrograph has provided a precise look at the giant exoplanet WASP-31 b. Researchers confirmed that the planet’s orbit is nearly perfectly aligned with its star's rotation. While attempting to scan the planet's atmosphere for chemical elements, the team found that the signal was heavily obscured by distortions caused by the planet passing in front of its star. Although previously suggested elements like potassium were not detected in this specific data set, the study highlights a major technical challenge: for planets with perfectly aligned orbits, it is incredibly difficult to separate the planet's atmospheric signature from the light of the star itself.

Scientific study

Precise measurement of WASP-31 b's Rossiter-McLaughlin effect and characterization of the planet transmission spectra (external link)