WASP-39

system

WASP-39 — a Sun-like star ~700 light-years away in Virgo, host to a puffed-up hot Saturn that made history: in 2022 JWST read the first UNAMBIGUOUS carbon dioxide in any exoplanet's atmosphere here — a milestone for the search for alien air. Descend to explore it.

Open in 3D viewSee WASP-39 in the live, interactive 3D map

Science

Classification

Type: Planetary system
Distance: ~698 light-years · its real distance from the Sun
Explore: Descend to see the star and its confirmed planets

How we know

Note: A real star system, shown at its measured position in the galaxy. Its star and confirmed planets — their measured sizes and how each was found — are on the cards inside; descend to explore them. Distances follow Gaia parallax; planet data follow the NASA Exoplanet Archive.

Discovery & history

Name: A designation from the Wide Angle Search for Planets (WASP) survey; no proper name.

WASP-39 b was found transiting in 2011. Because it is hot and remarkably low-density, its thick atmosphere is easy to read; in 2022 JWST's very first exoplanet observations delivered a textbook detection of carbon dioxide — the first clear CO₂ at any exoplanet — plus water, sulphur dioxide and clouds, opening a new era of atmospheric chemistry.

Images

Artist's impression of the puffy hot Saturn WASP-39 b and its star — an artist's concept, not a photograph. — NASA / ESA / CSA / STScI, M. Zamani (CC BY 4.0) · Wikimedia Commons

JWST transmission spectrum of WASP-39 b — the first unambiguous carbon-dioxide detection at any exoplanet (a data graphic, 2022). — NASA / ESA / CSA / STScI, J. Olmsted (CC BY 4.0) · Wikimedia Commons

Images from open archives · credit shown per image