Clouds
© NASA
A NASA sounding rocket to be launched from the Poker Flat Research Range, Alaska, between February 13 and March 3, 2017, will form white artificial clouds during its brief, 10-minute flight.

The rocket is one of five being launched January through March, each carrying instruments to explore the aurora and its interactions with Earth's upper atmosphere and ionosphere. Scientists at NASA's Goddard Space Center in Greenbelt, Maryland, explain that electric fields drive the ionosphere, which, in turn, are predicted to set up enhanced neutral winds within an aurora arc. This experiment seeks to understand the height-dependent processes that create localized neutral jets within the aurora.

For this mission, two 56-foot long Black Brant IX rockets will be launched nearly simultaneously. One rocket is expected to fly to an apogee of about 107 miles while the other is targeted for 201 miles apogee. Only the lower altitude rocket will form the white luminescent clouds during its flight.

Flying the two similar payloads simultaneously to different altitudes will provide researchers unprecedented vertical measurements within an aurora.

The launches will occur between 7 pm and midnight AKST. The launch decision is dependent on clear skies and auroral activity.

During the flight, a vapor tracer cloud of trimethyl aluminum or TMA will be deployed to allow scientists on the ground to be able to visually track the winds within the aurora.

Trimethyl aluminum reacts with oxygen when exposed to the atmosphere. The products of the reaction are aluminum oxide, carbon dioxide, and water vapor, which also occur naturally in the atmosphere. The amount of TMA used in the test is much less than that used in a typical July 4 fireworks display. It will be released at altitudes of 60-100 miles high and poses absolutely no hazard to the community.

More information on the NASA sounding rocket missions from the Poker Flat Research Range and the use of vapor tracers in science research is available at:

www.nasa.gov/soundingrockets

A live broadcast of the launch will be streamed on the Internet by the University of Alaska Fairbanks Geophysical Institute beginning about 20 minutes prior to the opening of the launch window. The web stream will be available at:

youtube.com/PokerFlatRR

In addition, the range launch communications can be monitored at:

http://stereo.wavestreamer.com:7519/index.html?sid=1