NASA's SPHEREx just read the skies of 37 'failed stars' — and found water and methane

Brown dwarfs are the in-betweeners of the cosmos: born like stars, but too small to ignite, drifting through space as oversized almost-planets. NASA's SPHEREx telescope, launched last year, has now read the atmospheres of 37 nearby ones in 102 colors of infrared light — and found water, carbon dioxide, carbon monoxide, and methane swirling in their skies, across a temperature range from a scorching 4,000°F (about 2,200°C) down to -10°F (about -23°C). The peer-reviewed census, led by Caltech's Zafar Rustamkulov, is the most detailed chemical portrait of these objects ever made — and a preview of what the telescope will learn about giant planets too.