Residents of Alaska's most populated regions are likely to miss out on the big light show headed earthward if atmospheric forecasters are right -- always a big if.
With the sun about to undergo a magnetic flip, University of Alaska physicists report that there has been a lot of activity on its flaming surface. A burst of solar storm-charged particles ejected days ago should collide with EarthEarth and set to collide with the atmosphere Thursday night.
That should trigger a good-size burst of northern lights.
"Weather permitting, active auroral displays will be visible overhead from Barrow to Anchorage and Juneau, and visible low on the horizon from King Salmon and Prince Rupert,'' the institute reports.
The problem for Southcentral Alaska is that the National Weather Service is predicting the sky will be full of clouds Thursday night. The clouds aren't supposed to start to break up until Friday night into Saturday, according to that agency.
Clouds are supposed to begin lifting on Friday night or Saturday morning with sunny skies predicted for Saturday and mostly clear forecast from Saturday night through Sunday night.
Unfortunately, the institute says the light display may be fading by then. It might still be visible on the horizon from Anchorage, but the best of it may be over.
Still, there is some good news. The complete magnetic flip of the sun -- with the magnetic north pole becoming the south pole and vice versa -- is expected to take months. The flip happens once every 11 years, and typically it's accompanied by increased aurora activity. The activity can be so intense it may affect radio transmissions and satellite communications in addition to prompting celestial light shows.
Those impacts should be minimal according to C. Alex Young, associate director for science in the heliophysics science division of the NASA Goddard Space Flight Center in Maryland. Young compared the amount of particles being flung into earth's atmosphere as part of the magnetic shift to hurricane season. Sometimes there are strong, large ejections; other times the ejections are rarer or low intensity. Big ones could affect communications, though only for those living close to the earth's magnetic poles. The last major power outage caused by solar particles occurred in Quebec when a hydropower grid went out for nine hours in 1989.
"The biggest (solar ejections) in history have happened on the way down from solar max," Young said. "It's possible, but highly unlikely."
Young said while it's impossible to know when the peak of the current solar maximum will occur, scientists predict will hit in the next few months or the beginning of next year. Young said it's worth noting that solar activity is often higher during the equinoxes, and that with both the fall equinox and solar maximum overlapping, those living in northern latitudes can expect serious aurora activity in the next month.
Weather permitting, of course.
Alaska Dispatch reporter Craig Medred contributed to this report. Contact Suzanna Caldwell at suzanna(at)alaskadispatch.com