(NASA/Solar Dynamics Observatory/Getty Images)

A geomagnetic storm caused Delta Airlines 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.

"The FAA is closely monitoring the current solar storm and the potential for more storms over the next few days, and will issue a Solar Radiation Alert if necessary. So far, radiation dose rates have not been high enough to trigger an alert," the agency said in a statement.

NASA said the six astronauts on the international space station are safe and won't need to shelter in place to ride out the storm.

Even though this is the strongest geomagnetic storm Earth has experienced in six years, the radiation has caused only minor problems.

"Operators are surely seeing a greater number of errors on their system that are causing them to work a bit harder, but we're not expecting satellites to stop," Douglas Biesecker, a physicist at the National Oceanic and Atmospheric Administration, told ABCNews.com.

Sky watchers in northern states may be able to see fairly vivid aurora displays tonight that resemble filmy white sheets shooting around the sky.

The storm was set off by a chain of events Sunday evening. A moderate solar flare erupted on the sun, which occurs tens of thousands of times every solar cycle, Biesecker said. The solar flare was associated with a coronal mass ejection, which is also a frequent occurrence. However, this particular one was big and sent a cloud of plasma with a magnetic field hurtling toward Earth at 4 million mph.

Earth experienced some of the radiation within an hour of Sunday's solar flare.

"The ones that escape propogate to Earth at the speed of light," Biesecker said.

The geomagnetic storm is expected to last for one day.

ABC News' Gina Sunseri and Matt Hosford contributed to this report