• Cheryl Lindo Jones via Flickr
  • Not an alien invasion: the aurora borealis over Chicago in 2006.

This has been a strange week here in Chicago. Boiling water turned to snow. (It also retained its ability to burn.) Steam rose from Lake Michigan and the Chicago River, at least in the parts where they weren’t frozen into modernist ice sculpture. If we still believed in signs and wonders, and that the world will end not in fire but in ice, a very good case could be made that this week is the beginning of end times.

But we don’t believe that sort of thing anymore. (Well, most of us.) Instead we can appreciate that supercold weather makes all sorts of cool shit happen. Even if, as that killjoy Tom Skilling has pointed out, it’s not really steam coming off the lake. It’s ice crystals.

And we still may not have seen the coolest scientific phenomenon of the week. That may be coming this evening, in the form of the aurora borealis, or the northern lights.

Technically, the northern lights have nothing to do with cold weather. They happen when electrons from the solar system interact with elements in the earth’s atmosphere, usually around the earth’s magnetic poles. Where it tends to be cold. Usually they don’t show up this far south.

But now space scientists at the National Oceanic and Atmospheric Administration (NOAA) say there was a huge sunspot eruption (technical term: coronal mass ejection) on Tuesday that sent a whole bunch of charged particles our way, and the disturbance in the atmosphere will be so great, we should be able to see northern lights all the way down here in Chicago, and maybe even in central Illinois. It takes a while for the particles to get to earth from the sun, so the aurora borealis won’t be appearing until this evening.

  • NASA Earth Observatory
  • The aurora borealis from the edge of the earth, 2011

That’s the good news. The bad news is that NOAA and the National Weather Service are also predicting heavy cloud cover (and more snow) across most of the upper midwest, except for a few patches in north-central Minnesota. If you start driving now, you might be able to make it to Bemidji before the show starts. Or you could do what people did 1,000 years ago: go off somewhere very dark and quiet and pray that the cloud cover will blow away, and then interpret the aurora as a sign of God’s mercy and a promise that it won’t get this frickin’ cold again for another 20 years.