The Northern Lights made their way down to the Chicago area Tuesday, but if residents are treated to another show Wednesday, there’s an important tool you can use to see them at their best.
A display of the Northern lights this far south is unusual, and Tuesday night we got a full show.
“The Northern Lights being seen in our area is generally pretty rare,” said Michelle Nichols of the Adler Planetarium. “We only get to see it two or three times a year.”
Nichols says the sun is the main reason we are seeing the lights, also known as the Aurora Borealis, with a phenomenon called a coronal mass ejection, or CME, helping spark the show.
“A coronal mass ejection is a release of a bubble of material from the sun, protons…electrons, and that stuff goes outward into the solar system,” Nichols said.
The Auroras form when that bubble interacts with the earth’s magnetic field. Every color, she said, has a meaning.
“A red color might be from glowing nitrogen, green is glowing oxygen, so those are the two main components of the earth’s atmosphere. ”The colors are telling you a gas that’s glowing and the altitude its occurring at.”
Even though the lights of the city often obscure events in the night sky, the Auroras Tuesday night could be seen in downtown Chicago as well as the suburbs. There are even reports that the lights could be seen in El Salvador which is at 13 degrees North latitude.
For most of us, the auroras are just a great light show, but in some industries, they can cause real problems. They can contribute to greater radiation around the earth’s poles, exposing people on popular polar air routes to additional radiation. That is less a concern for passengers than for crews whose exposure builds up over time. There have even been reports of GPS outages triggered by the lights accounting for automated machinery going off course.
“That’s something we’ll have to keep and eye on,” Nichols said.
On Wednesday night there is a chance of another aurora visible in the Chicago area. Chances are, you are carrying the best tool to see it right in your pocket. Your cell phone is almost built for the job. That’s because your cell phone can take advantage of advanced computational photography.
It sounds complex, but what that really means is your cell phone doesn’t just take one picture, it takes dozens of exposures and then uses math to stack them together. That way it can gather much more light.
The phone’s software can then use math to compare the exposures to reduce noise and motion shake. Your camera will also enhance the colors to get those vivid exposures that make auroras so exciting to see.
So how do you do it? First thing, get a hold of a tripod or another device to steady your phone when you take the picture.
Second, turn off the flash and switch the camera to night mode. It usually looks like a little crescent moon. That will turn on the low-light sensors and activate the A.I. to reduce shake.
That’s it. There is no need to adjust the shutter speed, the aperture or the ISO. Just start taking pictures. Auroras in this area are not common, but they are easy to save as digital images.