Twenty NASA personnel, a handful of university professors, four multimillion-dollar suborbital sounding rockets and one UAF electrical engineering student supported the successful launch of UAF professor John Craven's HEX2 mission from the Poker Flat Research Range last week.

Sujith Nair, a participant in the HEX2 launch, initially chose UAF for his graduate work in electrical engineering because of it's affiliation with PFRR rocket projects. On Thursday, Nair launched his masters thesis, the HEX2 Plasma probe, 95 miles into the atmosphere to measure ion densities.

Craven, the chair of the UAF Physics Department and a professor at the Geophysical Institute, directed the HEX2 mission. The goal of the mission was to gather data to understand the movement of the upper atmosphere, he said.

"We want to look at the response of circulation in the atmosphere to auroral heating," Craven said.

Nair's project provided verification of the mission's primary purpose: to deploy trimethylaluminum (TMA), a substance that reacts on contact with oxygen. Visible in the night sky as cloudy white smoke, TMA trails describing particle motion were captured by four ground-based cameras.

"My instrument is there to corroborate the wind pattern data deduced from the visual TMA trails by recording the movement of charged particles," Nair said. "As we see the TMA trails moving, the plasma probe will confirm that the electrons are also moving."

The aurora is caused by the interaction of high-energy plasma from the sun known as solar wind, with the Earth's magnetic field. In order to dissipate energy created by this interaction, electrons and protons are dropped into the upper atmosphere interacting with gasses to produce the aurora.

This interaction also creates electrical currents that heat the upper atmosphere initiating vertical convection and horizontal winds. These currents can disrupt radio communications and interfere with GPS, navigation and radar systems. An active aurora is the result of a greater particle disturbance in the atmosphere.

One of the most complex missions conducted from PFRR, four rockets were launched in under 16 minutes. Three rockets traveled along vertical arching trajectories defining a three dimensional space in the aurora. After reaching its desired altitude, the fourth rocket rotated to travel along a trajectory, horizontal to the direction of movement.

"With an experiment like this we can look at scales of motion in the atmosphere," said Mark Conde, an assistant professor of physics at the G.I. and a HEX2 collaborator. "Sampling in three dimensions will give us the best shot at successful data."

The HEX2 plasma probe was attached to the horizontal rocket with the purpose of detecting positively charged ions, to determine the ion density in the aurora.

"Our approach is to sweep the aurora," Nair said.

The plasma probe has no moving parts and gathers data as the rocket rotates along its trajectory. It is mechanically simple compared to the boom deployed Lagmuire probe, an instrument used since the 1970's to detect ion densities.

"This instrument will provide the relative plasma density with a slight compromise on accuracy, but it will enhance mechanical and aerodynamic stability and will not jeopardize the primary goal of the mission," Nair said.

Nair began working on the plasma probe in summer 2005, under Joe Hawkins a professor of electrical engineering at UAF and Bruce Johnson, creator of the plama probe.

The probe was initially designed and flown in Craven's HEX1 mission in 2004. However, unexpected results prompted scientists to modify launch conditions, Hawkins said.

"For HEX2, the idea is to wait for an active aurora, to fly the rockets through a more disturbed environment."

Nair also modified the device by increasing the collector surfaces from two to four and establishing a directional biasing scheme which repels electrons and attracts ions to the probe's surface, depending on it's location. These modifications are aimed at increasing the accuracy of the instrument.

"A preliminary look at the data shows an oscillating pattern of increasing and decreasing electrical current based on the rocket's rotation," Nair said. "This is expected and is verification that the instrument worked properly."

As the only university owned rocket-launching facility, Poker Flat provides University of Alaska students and faculty with a unique opportunity to explore upper atmospheric science and plasma physics.

"This project solidified concepts that I learned theoretically," Nair said. "It was a great learning experience working with NASA."