The conditions have to be just right. It has to be a specific type of plane, a certain cloud and a certain temperature.
But when it all comes together, you might see a hole in the sky.
What happens, NCAR scientists say, if all the conditions are right, the plane flies through a cloud, and punches a hole in it.
That could create rain or snow over that area. This has happened at DIA.
Andy Heymsfield, a senior scientist at NCAR, is researching clouds and precipitation development and the affects of clouds on climate.
He showed 9NEWS a satellite image that shows multiple holes or tracks in the sky made by planes.
Some of them can be 200 miles long, 10 to 20 miles wide and last for 2 or 3 hours.
"We might understand a little bit more about how we're interacting with our environment by understanding how these clouds are generated and how they affect their environment," Heymsfield said.
Scientists are still working on figuring out how often this happens. Of course it does occur on purpose in what's called seeding the clouds. When ski resorts for instance need it to snow, they can pay to try to make that happen.
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