Science

TOI-199b sits about 330 light-years from Earth, orbits a Sun-like star every 105 days, and holds an equilibrium temperature of roughly 352 K (79°C). That’s warm by terrestrial standards but downright mild for an exoplanet, where “hot Jupiter” atmospheres regularly top 1,500 K. A team led by Aaron Bello-Arufe at Penn State pointed JWST at a single transit of this world and pulled methane out of its atmosphere, making TOI-199b the first temperate giant exoplanet whose atmospheric composition has been directly measured. ...

When you look at galaxies through a telescope — scattered across the field like grains on dark cloth — it’s tempting to think they’re placed at random. They aren’t. Galaxies live on a structure so vast that the only metaphor that survives at scale is a web: long filaments of matter, hundreds of millions of light-years across, connecting dense knots of galaxy clusters and skirting nearly empty voids. This month, the largest survey JWST has carried out gave us the clearest map of that web to date, tracing it back to a time when the universe was barely a billion years old. ...

When I tell people the Andromeda galaxy is 2.5 million light-years away, the next question is almost always: how do you know? It’s a fair question. We’ve never sent anything past the outer edge of the Kuiper belt. The fastest probe humanity has ever launched would still take roughly 70,000 years to reach the nearest star. So how does anyone get from “I’m staring at a smudge above the rooftops of Nicosia” to “that smudge is around 24 quintillion kilometres away”? ...