Three NASA rockets are launching from Fairbanks, Alaska, to study the aurora and Earth’s upper atmosphere. The experiment seeks to reveal how auroral substorms impact the behavior of the upper atmosphere.

The experiment’s outcome could upend a long-held theory about the aurora’s interaction with the thermosphere. The theory states that heat from an auroral substorm causes the thermosphere’s vertical-motion churn. Additionally, the experiment could improve space weather forecasting, which is critical to devices such as GPS.

AWESOME

The experiment is titled Auroral Waves Excited by Substorm Onset Magnetic Events, or AWESOME. It includes one four-stage rocket and two two-stage rockets, which will launch at the same time in a three-hour period. The launch window is between now and April 6. For stargazers, this will create colorful vapor tracers across Northern Alaska.

Mark Condea, a space physics professor at the University of Alaska Fairbanks (UAF), leads the mission. NASA delivers, assembles, tests, and launches the rockets. It also involves about a dozen UAF graduate student researchers.

“Our experiment asks the question when the aurora goes berserk and dumps a bunch of heat in the atmosphere, how much of that heat is spent transporting the air upward in a continuous convective plume and how much of that heat results in not only vertical but also horizontal oscillations in the atmosphere?” Conde said.

Determining the dominant process will reveal the breadth of the mixing and the related changes in the thin air’s characteristics.

“Change in composition of the atmosphere has consequences,” Conde said. “And we need to know the extent of those consequences.”

Understanding the Aurora

The thermosphere reaches from about 50 to 350 miles above the surface. Most of it is what scientists call “convectively stable,” meaning minimal vertical motion of air because warmer air is already at the top due to solar radiation. Auroral substorms upset the stability in the middle and lower atmosphere. This leads to the theory that a substorm’s heat causes the thermosphere’s vertical-motion churn.

However, Conde acoustic-buoyancy waves are a more dominant mixing force than vertical convection. These waves are like water ripples in the air, moving both horizontally and vertically. As a result, the atmospheric changes caused by the aurora could be much broader than currently believed.

AWESOME’s practical goal is to better predict the impact of those changes.

“I believe our experiment will lead to a simpler and more accurate method of space weather prediction,” Conde said.