Starwatchers were out in force in northern Europe on Tuesday, hoping to see a spectacular showing of northern lights after the most powerful solar storm in six years.
They weren't disappointed.
"The lights appear as green and red mist. It's been mostly green the past few nights. I don't know if that's just special for Ireland," said Gerard O'Kane, a 41-year-old taxi driver and vice chairman of the Buncrana Camera Club in County Donegal in Ireland's northwest corner.
An aurora appears when a magnetic solar wind slams into the Earth's magnetic field, exciting electrons of oxygen and nitrogen.
The northern lights are sometimes seen from northern Scotland, but they were also visible Monday night from northeast England and Ireland, where such sightings are a rarity.
On Monday and Tuesday, the proton radiation from the eruption reached strong levels, the most powerful since October 2003. That mostly affects astronauts and satellites, but NASA said the crew on the International Space Station was not harmed and only a few minor problems with satellites were reported, Biesecker said.
Scientists have been expecting solar eruptions to become more intense as the sun enters a more active phase of its 11-year cycle, with an expected peak in 2013.
Delta Airlines had to reroute a handful of flights that were scheduled to fly over the North Pole today.
A Delta spokesman said the flights were shifted to fly further south in an effort to ensure consistent communications. The affected routes were between Detroit and the Asian cities of Shanghai, Beijing, Hong Kong and Inchon. United had to re-route one flight Monday and American reported no impact, but said the airline continues to monitor the situation.
The FAA said it was keeping close watch on the situation today but did not issue an alert.