Western Slope Skies
Tue October 9, 2012
The Northern Lights
One summer, when I was growing up, it was common to hear about sightings of the “northern lights” over Grand Mesa. Most of the stories came from high school kids staying out too late on dates. At the time, I scoffed at those stories, but have since learned that that summer happened to be during a particularly active sun cycle.
Auroras, or “northern lights”, occur when charged particles from solar storms are caught up in Earth’s magnetic field and energize nitrogen and oxygen atoms in the upper atmosphere. These excited atoms glow in pillars and curtains of green, red, and even pink. Right now, the sun is near the peak of its 11 year activity cycle.
Usually, auroras are only seen north of 45 degrees latitude. But, a giant solar storm this fall could make auroras visible from locations as far south as Mexico—including the Western Slope!
Here, auroras would appear just above the northern horizon. They’re best observed on clear, dark nights, away from lights. To find out when to look for them, listen for news alerts, or check the Auroral Map on the NOAA “Space Weather Now” web-site.
If you aren’t lucky enough to catch a northern light show from the Western Slope, you can often view real-time auroras on the Canadian Space Agency’s AuroraMax all-sky camera, which broadcasts nightly from Yellowknife during fall and winter.
Western Slope Skies is produced by members of the Black Canyon Astronomical Society.