What an amazing image! Those cresting wave forms? That’s the aurora seen from 518 miles up by the Suomi-NPP satellite. An intense display lit up the sky across northern Canada on Dec. 22 just hours after the winter solstice, when a mass of energetic particles from the sun smashed into Earth’s magnetic field and funneled down to the atmosphere below.
From twice the height of the International Space Station, the Suomi-NPP (National Polar-orbiting Partnership) satellite captured the scale of the storm, which stretched across British Columbia, Alberta, Saskatchewan, Manitoba, Nunavut, and Northwest Territories. None of this was visible from the continental U.S. — too far north for us to see — but a commonplace sight for the few who live at these high latitudes.
Northern Canada, Alaska and Siberia are the home turf for the auroral oval, a permanent ring of northern lights that contracts and expands according to what the sun sends Earth’s way. High-speed particles, mostly electrons, from solar storms, coronal holes and coronal mass ejections can cause the oval to flare up and thicken, producing auroras like the ones shown in these photos.
An instrument called a scanning radiometer collects visible and infrared photos of the land and atmosphere. One of the satellite’s main purposes is to improve our understanding of global climate change. Besides the lights of cities and industry, the radiometer detects dim light signals such as auroras, airglow, gas flares, and reflected moonlight. In the case of aurora, the sensor detected visible light as energized particles from the sun rained down from the Earth’s magnetic envelope and slammed into oxygen and nitrogen molecules in our atmosphere.
From the ground, we see sheets, curtains and dancing rays, but from the space these fold into eerie curls and waves. If the aurora didn’t look unearthly enough, it’s stranger from space.