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A high altitude version of northern Lights can create an adverse wind for some satellites in orbit, a new study reports.
Auroras help carry air pockets higher up Earth's atmosphere, increasing drag on spacecraft that revolve around the Earth at relatively low altitudes, researchers said in the new study.
"We knew these satellites were coming up against slowdowns and upwelling," said lead author Marc Lessard, a physicist at the University of New Hampshire, in a statement. communicated. "But during this mission, we were able to reveal some of the mystery that explains why this happens, discovering that the bumps are much more complicated and structured."
Related: Northern Lights 2019: When, where and how to see the northern lights
The mission mentioned by Lessard is Rocket Experiment for Neutral Upwelling 2 (RENU2), a brief suborbital flight launched from Norway in December 2015.
The RENU2 rocket has observed PFLs, which are weaker and less energetic than the "normal" aurora borealis that adorn postcards and posters.
PMAFs are also much higher, reaching 400 km above ground level, compared to about 100 km for their more familiar and picturesque cousins. PMAFs therefore transfer energy to the vaporous air in the upper part of the Earth's atmosphere, the study revealed.
And these "upwelling events" can complicate the life of satellites passing on a low Earth orbit.
"You can think of satellites traveling through air pockets or bubbles [as being] similar to those of a lava lamp, as opposed to a smooth wave, " Lessard said.
The aurorae of the Earth result from the penetration of charged particles of the sun into molecules of the atmosphere of our planet. This excites these molecules at higher energy levels, and they emit light. The color of this light depends on the molecule affected. Collisions involving oxygen generate yellow and green glow, for example, while nitrogen emits red, purple or blue when it is excited.
The Earth's magnetic field drives solar particles to the poles of the planet, which is why auroras are usually confined to high latitudes. But strong solar activity can intensify auroras, increase their power and extend their geographic reach. Such activity can also make PMAF upwelling events more important, the researchers said.
The new study was published last month in the journal Geophysical Research Letters.
Mike Wall's book on the search for extraterrestrial life, "Over there"(Grand Central Publishing, 2018, illustrated by Karl Tate), is out now. Follow him on Twitter @michaeldwall. Follow us on twitter @Spacedotcom or Facebook.
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