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Poker Flat rocket launch to study energy movement during aurora

Two sounding rockets are scheduled to launch from Poker Flat Research Range just minutes apart in an experiment aimed at learning how energy is transferred and dissipated during auroral displays. The findings could increase the understanding of factors affecting satellites in low Earth orbit.

The NASA-funded Ion-Neutral Coupling during Active Aurora experiment could launch from the range north of Fairbanks as early as Wednesday, March 23. The launch window closes April 7.

Assistant professor Stephen Kaeppler of Clemson University is the principal investigator. Space physicist Mark Conde of the �ֻ�ֱ�� Geophysical Institute is a co-investigator.

The INCAA experiment seeks to better understand what happens to energy from the solar wind after it reaches Earth’s magnetosphere, the shield that protects Earth from the solar wind.

Specifically, the experiment seeks information on how and at what altitude energy is transferred and dissipated from the magnetosphere to the ionosphere-thermosphere system, which reaches from about 50 miles to 400 miles above the planet’s surface.

It also seeks to understand how the interaction of the neutral thermosphere with the overlapping charged ionosphere affects the location of the energy transfer.

“Once you've suddenly dumped a lot of energy into the atmosphere, that energy has to go somewhere,” said Kaeppler, who has been involved in two previous launches at Poker Flat. “And it goes somewhere in a lot of different mechanisms.”

 “Sometimes it can change the neutral part of the atmosphere. It can knock satellites out of space,” he said. “And while a lot of satellites are high enough that it’s not much of an issue, it can be for lower-altitude satellites.”

As an example, Kaeppler pointed to the loss of several dozen of Elon Musk’s Starlink satellites during a February geomagnetic storm. The storm prevented the satellites from reaching orbit, causing them to fall back toward Earth and burn up as they descended.

The experiment will use two NASA rockets: a two-stage Black Brant IX that will launch first and carry a number of tracer payloads and a smaller two-stage Terrier-Improved Malemute that will carry instruments.

The chemical tracer payloads will be ejected at several 3-mile height increments once the rocket reaches an altitude of 80 miles, allowing scientists to monitor wind. There is no danger associated with the tracer release, which will create inert vapor streams up to about 200 miles altitude.

The second rocket will launch a few minutes later and carry instruments into the same area to analyze the neutral atmosphere and the ionosphere’s charged plasma. Several ground-based instruments will also be used.

The University of Calgary and the University of California, Berkeley are also involved in the research.

The experiment has an expanded component that is funded separately by the National Science Foundation and will use UAF’s High-frequency Active Auroral Research Program facility in Gakona. HAARP will acquire radar measurements of barium cloud motion for comparison with optical images of the clouds.

The Federal Aviation Administration will issue a temporary flight restriction from the surface up to 25,000 feet mean sea level within 2.5 nautical miles of HAARP to ensure general aviation can operate safely in the area.

The planned launch is the second this year at Poker Flat.

The �ֻ�ֱ�� Geophysical Institute owns Poker Flat, located at Mile 30 Steese Highway, and operates it under a contract with NASA’s Wallops Flight Facility, which is part of the Goddard Space Flight Center.

ADDITIONAL CONTACTS: Kathe Rich, Poker Flat Research Range director, 907-455-2103, ksrich@alaska.edu; Keith Koehler, NASA’s Wallops Flight Facility, 757-894-4152, keith.a.koehler@nasa.gov.

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