A two-stage Terrier-Black Brant rocket arcs through an auroral display 200 miles above Alaska's Poker Flat Research Range as the MICA mission investigates the underlying physics of the northern lights. In this long-exposure photo, the rocket's first stage has just separated and is seen falling back to Earth. The green arc toward the top of the photo is a scientific laser that's shooting into the sky to make profiles of the atmosphere. The beam only appears curved due to the wide-angle lens used to capture the photo.
A rocket experiment sampled the stuff of the northern lights over the weekend, adding some scientific substance to the great auroral views we've been getting from Earth and space.
Saturday night's launch from the Poker Flats Research Range in Fairbanks, Alaska, was part of a NASA-funded mission called the Magnetosphere-Ionosphere Coupling in the Alfven Resonator, or MICA for short. The project involves researchers from the University of New Hampshire, Cornell, Dartmouth, the Southwest Research Institute, the University of Oslo and the University of Alaska at Fairbanks.
A two-stage, 40-foot-tall Terrier-Black Brant rocket was sent arcing through the aurora to a height of 186 miles, sending down a real-time data stream as it flew. The payload was recovered 200 miles downrange, UNH said in a news release.
MICA's aim is to measure electric and magnetic fields and sample the charged particles in Earth's upper atmosphere while they're under the influence of a form of electromagnetic energy known as Alfven waves. These waves are thought to spark a particular type of auroral display: a well-defined band of shimmering lights, about six miles (10 kilometers) thick and stretching east to west, from horizon to horizon.
The northern (and southern) lights are the result of interactions between Earth's magnetic field and electrically charged particles streaming from the sun, in a region ranging from 60 to 200 miles or more in altitude. The mechanism behind the Alfven-wave displays is thought to be like a guitar string that gets "plucked" by energy delivered to the magnetosphere by the solar wind, said Marc Lessard, a UNH space physicist and one of the leaders of the MICA campaign.
"The ionosphere, some 62 miles up, is one end of the guitar string, and there's another structure over a thousand miles up in space that is the other end of the string. When it gets plucked by incoming energy, we can get a fundamental frequency and other 'harmonics' along the background magnetic field sitting above the ionosphere," Lessard said in the news release.
Physicists think the "string" takes the form of a beam of electrons accelerated by solar energy. "The process turns on an auroral arc, and then these waves develop on both sides of the resonator moving up and down. That's the theory, and it appears to be valid, but there's never been any really good measurement of the process in action. That's what MICA is all about," Lessard said.
A fisheye view of the Terrier-Black Brant rocket's ascent is captured by an automated camera near the entrance gate at the Poker Flat Research Range in Alaska.
In Alaska, a two-stage rocket is helping scientists understand how the lights are formed and how they impact satellites. NBC's Brian Williams reports.
The mission gathered data about other auroral phenomena as well. Cornell University's Steven Powell, another leader of the MICA campaign, reported in an email today that the initial results look promising.
"We can tell from the stripchart recordings that we have made excellent measurements of the electric fields, magnetic fields and charged particles (electrons and ions) associated with the aurora," he wrote. "These stripchart recordings are much like a patient's EKG in a hospital, and give us a 'quicklook' real-time glimpse of our data, so that we know that our instruments worked properly and the data quality is excellent. The detailed digital data was written onto data CDs, and our graduate students and scientific staff look forward to analyzing the digital data in the coming weeks and months."
February has been a good month for the northern lights, and last weekend was particularly good. SpaceWeather.com's Tony Phillips reported that Saturday night's light show extended as far southward as Iowa and Nebraska.
He said the display may have been intensified by the presence of a co-rotating interaction region, or CIR. Solar wind plasma tends to pile up in such regions, and that generally sparks better-than-usual auroras.
To see more of the results, check out SpaceWeather.com's aurora gallery, plus this video from Minnesota:
The northern lights glow in a video recorded on Saturday night by Bob Conzemius in Chippewa National Forest, north of Grand Rapids, Minn. "It was fun watching the auroras illuminate the fog and snow on the lake while listening to barred owls calling," Conzemius told SpaceWeather. com. "I may have heard a couple wolves howling in the distance, too."
The views have been great from the International Space Station as well. NASA's Gateway to Astronaut Photography From Space is offering a fresh batch of aurora videos from late January and February, including this must-see moonlit view of an outer-space passage from the North Pacific to the North Atlantic:
This Feb. 4 video was taken by the International Space Station's crew during a pass from the North Pacific Ocean, just west of Oregon, to the North Atlantic Ocean, east of Nova Scotia.
More auroral glories:
- Northern lights appear to wash over ship in Norway
- The sun sends Earth a valentine
- Aurora extravaganza glows in space
- Planet looks back at the northern lights
- Auroras spark awe across the north
- Solar weather stirs up super sights
- Northern lights go way, way south
- Speed through Lapland's lights
- Beautiful blasts from solar storms
- Get a video view of Canada's aurora
- Slideshow: The best of the northern lights
- Cosmic Log's auroral archive
Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding Cosmic Log's Google+ page to your circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.