The White Dwarf Opportunity with JWST

Editor’s note: AAS Nova is on vacation until 2 November. Normal posting will resume at that time; in the meantime, we’ll be taking this opportunity to look at a few interesting AAS journal articles that have recently been in the news or drawn attention.

Can life survive the death of its star? Planets orbiting white dwarfs present a unique opportunity to characterize rocky worlds in an attempt to answer this question. Scientists Lisa Kaltenegger and Ryan MacDonald (Cornell University) and collaborators have now shown that the upcoming James Webb Space Telescope (JWST) will be capable of establishing the atmospheric composition of planets transiting white dwarfs in their habitable zones. JWST could detect potential biosignatures in the atmospheres of these planets in as few as 25 transits — which, given the short transit duration for habitable-zone planets around white dwarfs, amounts to a small investment of observing time. For this reason, the authors argue that white dwarfs present a valuable target for future JWST observations. Check out the video below, in which Kaltenegger and MacDonald make their case for why we should explore white dwarfs in the search for life.

Original article: “The White Dwarf Opportunity: Robust Detections of Molecules in Earth-like Exoplanet Atmospheres with the James Webb Space Telescope, “Lisa Kaltenegger et al 2020 ApJL 901 L1. doi:10.3847/2041-8213/aba9d3
Cornell press release: Can life survive a star’s death? Webb telescope will explore