DENVER - A huge coronal mass ejection (aka solar burp) happened on the Sun last Tuesday. These giant explosions are many times larger than the Earth and blast charged particles into space.
If the eruption is facing the Earth, these particles travel toward our planet at 1 to 2 million miles per hour, so it takes about 3-4 days to travel the 93 million miles to Earth. http://solarscience.msfc.nasa.gov/CMEs.shtml
When the charged particles encounter the Earth's magnetic field, they are drawn toward the Poles. The particles energize gases in the high altitude of the atmosphere and make them glow - not unlike a fluorescent light.
Most of the time, the Aurora Borealis (Northern Lights) and the Aurora Australis (Southern Lights) are seen only at the higher latitudes as the polar magnetic fields pull the energy toward those regions.
When there is a strong coronal mass ejection, there is enough energy to excite gas molecules high above lower latitude locations such as Colorado. Tonight and early Friday, we have such a chance. Here is a link to the forecast for the aurora. http://www.swpc.noaa.gov/pmap/
The charged particles can do much more than just create colorful light in the sky, they also can disrupt power transmission lines and global communication. For that reason, the Space Weather Prediction Center, located in Boulder, Colo., keeps a close watch for these solar storms! http://www.swpc.noaa.gov/
We have a fair amount of cloud cover Thursday night across the region, but if you want to try and "see the lights", the best things to do are to dress warm, get away from bright lights and look toward the north!