..all that in a single day. So here I am back in Fairbanks for orientation for my next PolarTREC expedition.
After driving around in the wee hours we found a perfect spot to watch an amazing display of the Aurora Borealis.
Today we visited the Permafrost Tunnel and the Pipeline. Constructed in the 1960s, the Tunnel offers a peek into the last 40,000 years! When it was excavated, as luck would have it, they dug where there were all sorts of fossils such as Steppe Bison and Mammoth (whose fossils are very common up here). There are large ice wedges, strata illustrating changing climates and floods, bones that are 14,000 years old and Sedge plant remains carbon dated to 32,000 years old.
Here's part of the crew in the Permafrost Tunnel. That smooth looking part above them is an ice wedge.
They have even found frozen bacteria 30,000 years old. Very cool - in every sense of the word. It's a trip into a time machine and a treasure trove of information as to how this part of Alaska has changes from wet lowlands to the Arctic climate that it is now.
Susy Ellison and me at the pipeline.
Yet as interesting as this was, the perfection was awaiting us in the wee hours of the night. We were treated to a breathtaking show of the Aurora Borealis, also known as the Northern Lights. So what causes this? Well, solar winds take off from the sun (that's why they are solar winds, right?) at a speed of around 1 million miles per hour which makes the speed of the fastest jet look pretty lame. It takes about a day and a half for these winds to reach earth but that's when the show begins. Why? I'm glad you asked. Now the magnetic force generated by the earth's core creates a magnetic field. Remember your compass that will always point north? For now anyway, but that's another story...
Every few seconds the Aurora changes shape and sometimes color as the solar winds collide with earth's magnetic field.
We could talk A LOT about this, but let's move on. So when those highly charged electrons from the solar winds collide with the electrical and magnetic fields of earth, we see some pretty spectacular lights. This mainly occurs at the poles but I actually saw these lights in Chicago once. Usually you see green but there are other colors because different gases give off different colors depending upon their altitude and their level of excitement.
You can see a hint of color in this photo. Green is oxygen at about 100 miles up or so. When it goes above 150 miles it will look red.
I don't know about you, but I'm pretty excited about all this...and my upcoming expedition, of course. So please stay tuned...
Amazing stuff. The other gas that can be visible is nitrogen. Depending on how miles up it is you may see blue or a purple violet.