© Albert Jakobsson
A curtain of light is the backdrop for Iceland's Eyjafjallajökull volcano.
A curtain of light is the backdrop for Iceland's Eyjafjallajökull volcano.
On 3 April, the SOHO spacecraft spotted a cloud of charged particles called a coronal mass ejection (CME) shooting from the sun at 500 kilometres per second. This velocity suggested the front would reach Earth in roughly three days.
"It hit earlier and harder than forecast," says Doug Biesecker of the US National Oceanic and Atmospheric Administration's Space Weather Prediction Center in Boulder, Colorado.
Fortunately, the storm was not intense enough to interfere strongly with power grids or satellite navigation, but it did trigger dazzling auroras in places like Iceland (pictured).
Such storms highlight the uncertainty in the arrival times of CMEs, which can easily be 15 hours off predictions, Biesecker says. Better modelling of the solar wind, which can accelerate CMEs en route to Earth, could reduce the uncertainty.
Comment: Remember this?
Strange spiral: Residents in northern Norway were left stunned after the lightshow, which almost looked computer-generated, appeared in the skies above them
The meteor that turned night into day in Utah, Idaho and Nevada last November left a "noctilucent", or night-shining trail suspended in the space-dust laden sky, which high altitude winds later twisted into this spaghetti formation:
A photo believed to be depicting the meteor's aftermath, taken at 7 a.m. Wednesday, Nov. 18, 2009, from Clive, in western Tooele County, looking east toward Salt Lake City.