Stellar Blast Boils Away Some of a Planet's Atmosphere 34
The Bad Astronomer writes "Using a combination of Hubble and Swift observations, astronomers have apparently witnessed some of a planet's atmosphere being peeled away by a powerful stellar blast. HD 189733b orbits its star just 4 million km from the surface, and a few hours after Swift detected a big X-ray flare from the star, Hubble data revealed a big jump in hydrogen absorption as the planet transited the star. This indicates the planet's atmosphere was blasted off by the flare to the tune of a thousand tons of hydrogen per second. The planet is so hot it probably already loses a substantial amount of air to space all the time, but this spike is the first time a change in an exoplanet's atmosphere has been detected."
It could happen here (Score:5, Informative)
When stars go supernova, they sometimes release large Gamma Ray Bursts which are far more devastating to an atmosphere than X-rays. GRBs can cover great distances too. Currently a star named WR 104 which is 8000 light years from earth seems to be pointing straight at us. If it goes GRB when it explodes, we may be in for trouble. There's enough energy there (even at that insance distance) to cause wide spread extinction on the planet.
Interestingly enough, it may have already happened but the light from it, and/or the GRB, hasn't gotten here yet.
http://www.space.com/5081-real-death-star-strike-earth.html [space.com]
Re:It could happen here (Score:5, Informative)