| by Annette Trinity-Stevens
Bozeman became a temporary control center for a U.S. spacecraft last month, making it the first
time a space mission has been commanded from Big Sky Country.
The spacecraft, called TRACE for Transition Region and Coronal Explorer, was launched last year to
take high-resolution pictures of the sun. A rotating team of scientists, including three from Montana
State University in Bozeman, takes turn issuing daily instructions to the spacecraft from NASA's
Goddard Space Flight Center in Greenbelt, MD.
But last month, when it was MSU's turn to issue the daily plans, the two Bozeman scientists up for
duty didn't want to do it.
"It's intense," commented MSU postdoctoral researcher Brian Handy. "A week is about all a planner
can take."
The workload, however, wasn't what made Handy and MSU postdoctoral researcher Charles Kankelborg
hesitate when it was their turn to go Goddard. Instead, it was science. They wanted to go to a solar
physics meeting in California, scheduled close enough to the TRACE assignment to make attending the
meeting almost impossible.
The third MSU planner, graduate student Meredith Wills, had already done her stint at Goddard.
The solution was to transform Handy's cubicle in the MSU Engineering/Physical Sciences Building
into "mission control" during the week of Aug. 16-22. Handy issued the spacecraft's daily command
load from the Bozeman campus to Goddard Space Flight Center over the Internet.
From Goddard, the commands were relayed to one of two groundstations and up to the spacecraft,
a process that takes just minutes and is similar to sending an email message, the scientists said.
"This is the first time a U.S. space mission has been operated from Montana," MSU physicist and
one-time astronaut Loren Acton recently bragged to university administrators.
To make it possible, Handy imported from NASA's Goddard Space Flight Center the correct software
and did most of the troubleshooting. The operations planner has to tell the spacecraft which of
about seven different extreme-ultraviolet or ultraviolet wavelengths the telescope should use to
take its pictures. He or she also must tell the telescope which region of the sun to focus on,
since it can see only a fraction of the sun's surface at a time.
And that's the easy stuff. The toughest part of the planner's job is communicating with operators
from three other solar satellites and as many as 25 ground-based solar observatories around the
world. The international group must reach consensus on what the TRACE spacecraft should do so the
planner can issue commands by 2 p.m. the day before the orders go into effect.
"So there's lots of discussion about priorities, all evolving in real time in response to what the
sun is doing," Kankelborg explained. "As soon as the scientists all agree to look at region A it
seems to cause the sun to develop suddenly a much more active region somewhere else," he quipped.
The group is especially interested in an area of the sun called the transition region. That's a
narrow section between the star's surface and the outer halo, or corona, where temperatures go from
10,000 degrees Fahrenheit to more than 1 million degrees. Acton and the other scientists want to
know why the corona is so much hotter than the rest of the star.
TRACE, from its orbit 400 miles above Earth, can capture the sun's storms, flares and eruptions
in unprecedented detail and time resolution, the scientists said. Handy, in fact, helped build
part of the spacecraft's telescope while an MSU graduate student.
It's likely the MSU team will command TRACE from Montana again, said MSU solar physicist Piet
Martens, especially as the campus migrates to its Internet2 connection, a high-speed backbone
just now coming online.
"That's definitely the future," Martens said.
But that won't completely eliminate the need for weekly jaunts from Bozeman to Goddard Space
Flight Center by Handy and the others. TRACE planners have to communicate with other solar missions
operated out of Goddard, and that level of cooperation between the missions would be lost if TRACE
operations were based in Montana, Martens said.
Annette Trinity-Stevens is the MSU Research Editor.
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