A Scorching Planet Grew Two Tails ⚡ экспресс
By observing the ultra-hot Jupiter WASP-121b for the first time continuously over an entire orbit with the James Webb Space Telescope, scientists detected helium absorption nearly 60% of the time. This proved the existence of a powerful atmospheric outflow that splits into two tails: a leading tail (moving toward the star) and a trailing tail (pushed away by radiation). Shifts in spectral lines revealed that the gas remains dense over vast distances. These tails are comet-like, but their dynamics are more complex—current models can’t yet accurately describe the mass loss.
Planet WASP-121b orbits so near its star that the fierce heat boils its atmosphere away, streaming like a comet's tails. With the James Webb Space Telescope, astronomers continuously watched this process for the first time. They found that helium from the atmosphere is pulled into two enormous plumes, stretching across 60% of the orbit—hundreds of millions of kilometers. One tail, pushed by stellar radiation, surges ahead of the planet and falls onto the star. The other trails behind and escapes into space. The planet is morphing into a comet-like body, shedding its gaseous envelope. Such twin tails had never been seen in their full extent before. This helps us understand how swiftly gas worlds perish under alien suns. The observations relied on a special glow from helium, allowing light analysis to detect even the thinnest layers of the atmosphere—like peering deep into space weather.
🎯 The unique glow of helium lets us peek into the uppermost, bloated layers of exoplanet atmospheres—regions where ordinary light can't reach.