for National Geographic Today
Even in the wake of the Columbia space shuttle tragedy, long-planned NASA missions continue. The first post-Columbia flight, an unmanned rocket, lifted off last Thursday from White Sands, New Mexico.
As early as next week, at the Poker Flat Research Range, 30 miles (50 kilometers) northeast of Fairbanks, Alaska, NASA will send an unmanned rocket to probe the shimmering spectacle of the northern lights, or aurora borealis. The rocket's five-minute streak across the heavens will help measure how solar winds and the resultant aurora affect earthly communications and navigation.
On Tuesday, a NASA team arrived at Poker Flat to prepare for the two-rocket "Horizontal E-region Experiment," or HEX.
By coincidence, Poker Flat hosted NASA's first rocket launch after the 1986 Challenger shuttle disaster. Post-Challenger safety precautions still apply at the range.
"We've got recreation near us, we've got homeowners near us, we've got calving grounds and bird nesting areas near us," said Poker Flat operations controller Kathe Rich. "We need to pay attention to things like that."
The first HEX rocket, slated to soar about 100 miles (160 kilometers) up, follows a program that angles it in mid-flight to enter the aurora horizontally. If the steering mechanism fails, a built-in "flight termination system"an explosive devicedestroys the third-stage booster.
The new mission could blast off between Feb. 18 and March 8, depending on clear skies and the right conditions. Probing the aurora is "like hitting a moving target," said HEX project director Mark Conde, a physicist and assistant professor at the University of Alaska-Fairbanks.
Timing the Launch
In aurora research, timing is everything. Aurora watchers know that the display can fill the sky for hours or disappear in an instant.
Conde's responsibility is to signal the launch when he senses that the curtain of lights will remain stable for the duration of the rocket's brief flight.
Conde must eyeball the right momentliterally. He has long been going out at night with binoculars to get the cues he needs. "Every night," he said, "I watch the sky and say, 'Could I launch now?"'
The northern lights are powered by so-called solar wind, high-energy ionized particles emitted by the sun that form an electric field around the Earth. This field accelerates electrons, which then bombard gases in the Earth's upper atmosphere and cause them to produce a light show of colors.
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