A comet-like planet beyond our solar system is losing a lot more atmosphere in its vast tail than previously thought, intriguing astronomers and sparking new questions about how planets evolve with their parent stars.
The exoplanet WASP-69b, a hot, puffy gas giant 160 light-years from Earth that circles its host star in a speedy 3.9 days, first rose to fame in 2018 when astronomers found a possible comet-like tail of gas leaking from the planet's atmosphere. That tail, which was thought to be just a tiny trail of helium particles, if it existed at all, is now estimated to be at least 350,000 miles long (563,270 kilometers) — about seven times the width of the planet — as its its atmosphere is blown away by a steady barrage of solar wind from its star.
