A team of astronomers has made a groundbreaking discovery using the James Webb Space Telescope (JWST) to study the star TRAPPIST-1, one of the most famous exoplanet host stars. The research revealed hidden magnetic features on the star’s surface, which will help scientists better understand stellar behavior and the habitability of nearby worlds.
TRAPPIST-1 is a red dwarf star hosting seven known exoplanets and has been a frequent target for JWST observations. However, its high level of activity makes it challenging to analyze the atmospheres of its potentially habitable planets. The team found that magnetic features on the star’s surface, such as starspots and faculae, act like noise, interfering with attempts to clean their exoplanet observations.
Using time-resolved observations from JWST’s NIRISS instrument, researchers were able to study four stellar flares in incredible detail. They discovered a persistent feature in the spectral flux during one of the flares, which they believe is caused by structural changes on the star’s surface induced by flares. The analysis revealed that this brightening is not due to flare decay, but rather the disappearance of part of a dark magnetic feature.
This research marks the first measurement of the spectrum of a magnetic feature on an M8 dwarf star. The findings have significant implications for exoplanet research, as they provide scientists with crucial data needed to clean transmission spectra and improve our ability to assess habitability and search for biosignatures around red dwarf stars.
Source: https://www.universetoday.com/articles/stellar-flares-unveil-hidden-magnetic-secrets-of-trappist-1