Poker Flat to launch three NASA rockets in single aurora experiment

Three NASA rockets are set to launch from Poker Flat Research Range 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 Geophysical Institute owns Poker Flat, located 20 miles north of Fairbanks, and operates it under a contract with NASA’s Wallops Flight Facility, which is part of the Goddard Space Flight Center.

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 all three rockets should be visible across much of northern Alaska. The launch window is March 24 through April 6.

To receive updates about the launches, text PFRRLAUNCHES to 866-485-7614. Updates and a live feed will be provided on the Poker Flat Facebook page.

The mission is led by UAF space physics professor Mark Conde of the Geophysical Institute and UAF College of Natural Science and Mathematics and involves several UAF graduate student researchers at several ground monitoring sites. NASA and some of the nation’s top universities are also participating. 

“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 oscillatory waves that involve both vertical and horizontal motion 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 for communication, navigation and spacecraft operations,” Conde said. “And we need to know the extent of those consequences.”

All of the thermosphere, which reaches from about 60 to 350 miles, is what scientists call “convectively stable.” No convection occurs because the warmer air is already at the top, due to absorption of solar radiation.

Energy and momentum injected into the middle and lower thermosphere by auroral substorms, at roughly 60 to 125 miles altitude, may upset that stability.

Entrenched theory states that the aurora heats the middle and lower thermosphere and that the resulting vertical convection is the principal driver of thermospheric churn.

Conde believes instead that acoustic-buoyancy waves are also important and may at times be the dominant mixing force. Because acoustic-buoyancy waves travel vertically and horizontally from where the aurora hits, the aurora-caused atmospheric changes could be initiated over a much broader area than would be expected from simple upward convection alone. 

Better prediction of impacts from those changes is the AWESOME mission’s practical goal.

“If you’re in the business of trying to predict what would happen over California, for example, I believe our experiment will allow forecasters to use simpler and potentially more accurate methods of space weather prediction,” Conde said.

Two two-stage, 42-foot Terrier-Improved Malemute rockets will respectively launch from Poker Flat about 15 minutes and an hour after an auroral substorm begins. A 70-foot, four-stage Black Brant XII rocket will launch about 45 minutes after the second rocket. 

The first two rockets will release tracers at altitudes of 50 and 110 miles to detect wind movement and wave oscillations. The third rocket will release tracers at five altitudes from 68 to 155 miles.
 
Pink, blue and white vapor traces should be visible from the third rocket for 10 to 20 minutes.

Launches must occur in the dawn hours, with sunlight hitting the upper altitudes to activate the vapor tracers from the third rocket but darkness at the surface so ground cameras can photograph the tracers’ response to air movement.

A dozen UAF student and staff researchers, including Poker Flat Chief Scientist Don Hampton, will operate ground observation stations at Utqiagvik, Kaktovik, Toolik Lake, Eagle, Venetie, and Poker Flat.

The experiment involves several partner institutions: University of Michigan, Cornell University, Clemson University, Penn State, NASA’s Goddard Space Flight Center, NASA’s Wallops Flight Facility, and two nonprofit science organizations — SRI International and The Aerospace Corp. 

NASA will have approximately 50 NASA Wallops Flight Facility personnel, including civil servants and contractors, at Poker Flat during peak launch operations. NASA will also have about six people on site from its science team.