August 28, 2012 | 7
Here’s an eruption from the sun that happened just a few days ago. It is a coronal mass ejection that loops out from the sun, looking slightly like a lightbulb that has just switched on. But it’s a far cry from a 60 watt bulb – the temperature of the solar corona where the bubble erupts is around a million degrees Celcius.
The frames from this video were taken by Solar and Heliospheric Observatory’s (SOHO) Large Angle and Spectrometric Coronagraph (LASCO) C2 instrument, that blocks light from the main disk of the sun to better see the sun’s atmosphere.
Coronal mass ejections, CMEs, are bursts of charged particles that hurtle through space at millions of miles an hour. They can make for pretty images. But they can also be pretty damaging too, if Earth gets in their way. In the past CMEs and similar phenomena called solar flares have caused power outages, radio blackouts and more.
This burst comes a month after scientists spotted one of the fastest CMEs since STEREO launched in 2006. That eruption would almost have been big enough to cause a geomagnetic storm as severe as the Carrington Event of 1859, during which aurorae were visible as far south as Hawaii and were bright enough in the northeastern US to read a newspaper by in the middle of the night. (Though if there was an aurora going on overhead I think I’d probably pay more attention to that.) But, luckily, the CME that erupted in July this year was pointing safely away from us.
Still, all these solar storms are slightly unnerving. Especially as we know the sun is approaching its next peak in activity in spring 2013.
So now is probably a good time to point to my feature at BBC Future from earlier this year, about how scientists are developing new techniques to predict solar storms (UK residents will want to go here instead).
Let’s hope the sun’s bright idea wasn’t a huge flare to be hurled in our direction.