Give those rocket scientists some clear skies, with the moon below the horizon. And it’ll be time for another blast.

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NASA Visible Earth

Update: Four NASA suborbital sounding rockets launched from Poker Flat Research Range early Valentine’s Day and drew vapor trails into a shimmering aurora display, according to a release from the Geophysical Institute.

The experiment, called HEX2, was intended to give scientists insight into the behavior of high altitude winds associated with the aurora. Researchers were able to watch the movement of the vapor trails from Poker Flat, about 30 miles north of Fairbanks.


More details from the Geophysical Institute:

John Craven, a professor of physics at the University of Alaska Fairbanks
Physics Department and the Geophysical Institute, was lead scientist for
HEX2, in which four rockets took off from Poker Flat in a span of 16
minutes, beginning at 12:22 a.m. Alaska Standard Time. Three rockets
followed a traditional arcing trajectory, reaching an altitude of
approximately 125 miles. Following the first-stage burnout of the second
rocket, an onboard control system turned the experiment section of the
rocket to a nearly horizontal position. It flew through the aurora about 95
miles up. Each of the rockets carried an experiment that released puffs of
trimethylaluminum, a harmless substance that glows when exposed to oxygen.
The flights lasted for about seven minutes.

Scientists on the ground in different northern locations photographed the
chemical trails. Two were in Fort Yukon, one each at Toolik Lake and
Coldfoot, and two were in Old Crow, in the Yukon Territory. Their images and
digital recordings will be used to determine the motion of upper atmospheric
winds.

“In terms of auroral activity, it seemed to be right out of the requisition
we wrote,” Craven said. “The currents were there, the heating of the
atmosphere was there. It was all very successful. We had 14 pieces of data
(we wanted to get), and it looks like we’ve got 12 for sure, and that’s
pretty good.”

So far, nine rockets have been launched this winter into auroras from the range, with one last rocket launch to come.

Early Tueday morning, a sounding rocket shot into an aurora display in an investigation of the power source behind pulsating auroras.

“We launched … with 5 seconds left to spare in the window for the night,” the group reported in its morning update. “All deployments and maneuvers seemed to work amazingly well. More news when we know more.”

A release from the Geophysical Institute added more detail:

Marc Lessard of the physics department at the University of New Hampshire
was the principle investigator for the experiment to investigate various
aspects of pulsating aurora. The 662 pound experiment housed in the nose
cone of a 65-foot Black Brant XII rocket arced above the atmosphere 408
miles above northern Alaska. Pulsating aurora is a subtle type of aurora
that seems to blink on and off in large round patches.

Lessard’s experiment, called ROPA (Rocket Observations of Pulsating Aurora),
was complex even by rocket-science standards. It had a main instrument
cluster, known as a payload, and three sub-payloads, which separated early
after the rocket cleared the upper atmosphere at an altitude of 140 miles.

Two of the sub-payloads had their own rocket motors, propelling them away
from the main payload where they obtained measurements of the pulsating
aurora, which occurred near the latitude of Toolik Lake on Alaska’s North
Slope.

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Black Brant XII rocket

Dirk Lummerzheim of the University of Alaska Fairbanks’ Geophysical
Institute was on the ground at Toolik Lake. During the launch, he identified
what looked like pulsating aurora in the all-sky camera at the research
station there.

Researchers from NASA’s Wallops Flight Facility in Virginia were looking at
data from the launch as soon as it was available, before 5 a.m. Alaska
Standard Time. Scientists think pulsating auroras get their power from the
Van Allen belts, radiation belts far from Earth. Lessard’s team also used
the rocket to measure electrical current flow related to pulsating auroras
and to produce visual images from within the pulsating aurora.

The next launch will investigate waves generated by the aurora, in an project led by Jim LaBelle, a professor of physics and astronomy at Dartmouth College. In an experiment called CHARM, LaBelle will use one Black Brant XII rocket on a night with a very active aurora north of Kaktovik to obtain the best results.