It was a good night at Poker Flat Research Range in Alaska last night. Conditions were go for the launch of four rockets straight into the northern lights near the fringe of Earth’s airy envelope. The goal? To study how auroral, radiation belt and energetic particles from the Sun affect the composition of the upper atmosphere.
Called the Mesosphere-Lower Thermosphere Turbulence Experiment, or M-TeX, and the Mesospheric Inversion-layer Stratified Turbulence, or MIST, each rocket released trymethyl aluminum (TMA), a liquid used as a tracer of upper atmospheric winds. When released into the air it turns into bright, white smoke. Scientists at various ground stations photographed the evolving and expanding clouds of vapor to understand wind patterns in the rarefied regions where the aurora forms – usually 50-87 miles high. TMA vapor tracers do not pose a risk to health or the environment, according to NASA.
“Recent solar storms have resulted in major changes to the composition of the upper atmosphere above 49 miles (80 km), where enhancements in nitrogen compounds have been found,” said Richard Collins, M-TeX principal investigator from the Geophysical Institute at the University of Alaska, Fairbanks. ”These compounds can be transported into the middle atmosphere where they can contribute to ozone destruction.”
While the compounds can be transported to the lower atmosphere, it’s not a guarantee. That all depends on the roles of heating and turbulence produced by the onslaught of solar particles and radiation. That’s why scientists are doing the studies in the first place – to determine how materials in the upper atmosphere mix with those in the middle and what effect that might have on everything from air pollution to satellite drag.
Satellite drag is the retarding effect even the wispy air near the edge of outer space exerts in slowing down an orbiting satellite and changing its orbit. Large amounts of energy from auroras can heat the upper atmosphere, causing it to expand and increase satellite drag.
Launching rockets into the aurora. Audacious and sure to help us better understand how space weather affects our more meteorological variety.