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I have not yet, but I definitely plan to. I was up in Alaska recently too...but at the wrong time of year. In Anchorage, while it got dark after 10:30 P.M., it's just not a good time of year to see the aurora. And up in Nome, though the sun set at 12:30 A.M. or so when I was there, it never got darker than twilight (at this time of year anyway).

I've heard that, at least in Alaska and Canada, the best time to see the Aurora Borealis is in the fall and winter, and on VERY dark, clear, crispy cold nights. And certain colors appear in certain areas of the north (so I was told by a lifelong Nome citizen). In Nome, they get greens and blues. Same in southern Alaska. In Fairbanks, which apparently is THE place to view the aurora, they get all the colors - greens, blues, yellows and reds! Amazing! I will be going back someday, and I surely plan to see them. I heard too that, at certain special quiet times, you can actually hear them. They make a soft, electrical crackling sound.

But interestingly enough, has anyone ever seen the Aurora Australis? The "Southern Lights"? (heh heh) I'll bet maybe some of our friends in the southern countries of South America, or perhaps southern Australia and New Zealand (and Tasmania) have, yeah? That'd be cool too...

Auroras are produced by the collision of charged particles from Earth's magnetosphere, mostly electrons but also protons and heavier particles, with atoms and molecules of Earth's upper atmosphere (at altitudes above 80 km). The particles have energies of 1 to 100 keV. They originate from the Sun and arrive at the vicinity of Earth in the relatively low-energy solar wind. When the trapped magnetic field of the solar wind is favourably oriented (principally southwards) it reconnects with Earth's magnetic field, and solar particles enter the magnetosphere and are swept to the magnetotail. Further magnetic reconnection accelerates the particles towards Earth.

The collisions in the atmosphere electronically excite atoms and molecules in the upper atmosphere. The excitation energy can be lost by light emission or collisions. Most aurorae are green and red emission from atomic oxygen. Molecular nitrogen and nitrogen ions produce some low level red and very high blue/violet aurorae. The light blue colors are produced by ionic nitrogen and the neutral nitrogen gives off the red and purple color with the rippled edges. Different gases interacting with the upper atmosphere will produce different colors, caused by the different compounds of oxygen and nitrogen.