NASA to launch three rockets from Alaska in single Aurora experiment
by Rod Boyce, NASA's Goddard Space Flight Center
Three NASA-funded rockets are set to launch from Poker Flat Research Range in Fairbanks, Alaska, in an experiment that seeks to reveal how auroral substorms affect the behavior and composition of Earth's far upper atmosphere.
The experiment's outcome could upend a long-held theory about the aurora's interaction with the thermosphere. It may also improve space weather forecasting, critical as the world becomes increasingly reliant on satellite-based devices such as GPS units in everyday life.
The University of Alaska Fairbanks (UAF) Geophysical Institute owns Poker Flat, located 20 miles north of Fairbanks, and operates it under a contract with NASA's Wallops Flight Facility in Virginia, which is part of NASA's Goddard Space Flight Center in Greenbelt, Maryland.
The experiment, titled Auroral Waves Excited by Substorm Onset Magnetic Events, or AWESOME, features one four-stage rocket and two two-stage rockets all launching in an approximately three-hour period.
Colorful vapor tracers from the largest of the three rockets should be visible across much of northern Alaska. The launch window is March 24 through April 6.
The mission, led by Mark Conde, a space physics professor at UAF, involves about a dozen UAF graduate student researchers at several ground monitoring sites in Alaska at Utqiagvik, Kaktovik, Toolik Lake, Eagle, and Venetie, as well as Poker Flat. NASA delivers, assembles, tests, and launches the rockets.
"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.
Confirming which process is dominant 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 Thermosphere and Auroras
The thermosphere, which extends from about 50 to 350 miles above Earth, typically exhibits stability. The warmer air sits above colder air, resulting in minimal vertical movement due to the natural stratification caused by solar radiation absorption. Auroral substorms disrupt this equilibrium, injecting energy and momentum into the thermosphere, particularly in the middle and lower regions (around 60 to 125 miles up).
| Thermosphere Layer | Altitude (miles) | Characteristics |
|---|---|---|
| Lower Thermosphere | 50 - 125 | Influx of solar activity leading to lower stability, potential for mixing. |
| Middle Thermosphere | 125 - 200 | Domination of acoustic-buoyancy waves, heat distribution affected by auroras. |
| Upper Thermosphere | 200 - 350 | Stable temperatures; high-energy particles contribute to overall heat but minimal mixing occurs here. |
Objectives of the AWESOME Experiment
The primary aim of the AWESOME experiment is to distinguish the role of acoustic-buoyancy waves from traditional vertical convection processes in the thermal behavior of the atmosphere during auroral activity. The complete understanding of these processes could lead to enhanced predictions of space weather impacts.
Key Research Questions
- What is the dominant process for atmospheric mixing during auroral substorms?
- To what extent does auroral heat affect the composition and characteristics of the atmosphere?
- Can we improve current models of space weather prediction based on findings from this experiment?
Launch Details
The three rockets set to be launched are as follows:
- Rocket Type: Four-stage Black Brant XII
- Height: 70 feet
- Launch Time: Five minutes after the second rocket
Additionally, two Terrier-Improved Malemute rockets, each 42 feet tall, will provide data approximately 15 minutes and one hour after auroral phenomena begin.
“When the aurora goes berserk and dumps heat into the atmosphere, understanding its implications could redefine space weather forecasting,” – Mark Conde, Lead Researcher.
