[meteorite-list] Alabama Researchers Work On Laser Systems To Deflect Asteroids

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 22 Feb 2007 23:36:00 -0800 (PST)
Message-ID: <200702230736.XAA02192_at_zagami.jpl.nasa.gov>

Office of News Services
University of Alabama-Huntsville

For more information:
Ray Garner, (256) 824-6397

2/20/2007

UAH researchers working on laser system to deflect asteroid on collision
path with Earth

A team of scientists and engineers at The University of Alabama in
Huntsville (UAH) are conducting research that could one day save humanity
from asteroids threatening Earth.

UAH Laser Science and Engineering Group (LSEG), headed by Dr. Richard Fork,
professor of Electrical and Computer Engineering, is conducting research
into characterizing and deflecting asteroids that may endanger Earth.

It sounds like science fiction, but Fork, who has a doctorate from
Massachusetts Institute of Technology and more than 40 years of experience
working with lasers, said someday it could be possible to locate a laser in
space or on the moon to look at the properties of asteroids and perhaps
alter their trajectories away from Earth.

The research has students excited about using lasers for space-related
applications. Graduate student Blake Anderton wrote his master's thesis on
"Application of Mode-locked lasers to asteroid characterization and
mitigation." Undergraduate Gordon Aiken won a prize at a recent student
conference for his poster and presentation "Space positioned LIDAR system
for characterization and mitigation of Near Earth Objects." And members of
the group are building a laser system "that is the grandfather of the laser
that will push the asteroids," Fork said.

Anderton said his thesis discusses "a way to look at asteroids at maximum
range, which means early detection." According to his calculations, an
asteroid could be characterized up to 1 AU away (1.5 x 10 to the 11 meters).
Arecibo and other radar observatories can only detect objects up to 0.1 AU
away, so in theory a laser would represent a vast improvement over radar.

Anderton, who grew up on a farm in Moulton, Ala., is an engineer at Raytheon
Corp. in Huntsville. He said the project was a good one for him at this
point in his career because of his interests in optical and laser physics.
At Raytheon he's involved in radar work for the National Missile Defense
radar systems, but he's poised to move into optical and laser physics work,
so the masters degree in electrical and computer engineering with an
emphasis on optics helped him prepare for his next job assignment.

The thesis was a stepping stone that "opened doors" for him at his job, he
said. But Anderton added he has a personal interest in the asteroid
mitigation problem.

"We only have one Earth and you don't want to lose it."

Anderton shared a LSEG office with undergraduate Gordon Aiken. The two
students talked about their interests. The result of their collaboration is
a sharing of knowledge in their academic research pursuits.

Aiken started out in mechanical engineering, then transferred to optical
engineering when he discovered that UAH is one of just a few colleges in the
U.S. with an undergraduate program in optical engineering.

When Fork spoke of his research to one of Aiken's engineering classes, Aiken
expressed interest and landed a REU grant (Research Experience for
Undergraduates) for the summer of 2006.

At the end of the REU, Aiken made a presentation on what he'd learned, and
Dr. Vernhard Vogler, of UAH's Chemistry Department, suggested Aiken submit
his poster to a new annual UAH student research conference, held last year.

Aiken won the prize for best undergraduate poster and presentation.

"I really like optics. I wanted to get into the field of working with
lasers," said the sophomore, who served as a medic in the Army before coming
to UAH. "The school has been amazing for me ... If you show interest,
they're going to find something for you to do. This has all fallen into
place for me." Putting graduate students together with undergraduates is a
great idea, he noted.

"It's a good mixture of talent."

Fork said the current research relates back to work he performed in the
mid-1980s, when he and other researchers at AT&T Bell Laboratories developed
the first femtosecond lasers. They used one of the lasers to ablate material
by ultra-intense laser pulses with femtosecond time resolution ("Femtosecond
imaging of melting and evaporation at a photo excited silicon surface," M.
C. Downer, R.L. Fork and C.V. Shank, Journal of the Optical Society of
America B2,595-599 (1985)).

"The laser we are developing now is also being developed to ablate
materials," Fork said, but the device would be "a substantial distance" from
the target. The system includes an argon laser, a mode-locked Ti-sapphire
oscillator, a regenerative Ti-sapphire amplifier, a doubled neodymium-yag
pulsed laser and helium-neon line-up lasers, according to Dr. Fork.

The short-term goal of the work is "to amplify femtosecond pulses to high
peak power at high average power for remote sensing," using unique features
associated with the high pulse intensity, Fork said. The work is funded by
the U.S. Army and involves a local company that employs several of Fork's
former students. The research does not concern characterizing or deflecting
asteroids, but Fork sees a connection.

"My vision is that this system is the progenitor of the laser that could
characterize and deflect asteroids," he said. (UAH)

IMAGE CAPTION:
[http://uahnews.uah.edu/newsImages/optics1407.jpg (66KB)]
UAH students Dane Phillips (foreground) and Gordon Aiken perform optics
research in a campus laboratory. Phillips is a doctoral student while Aiken
is an undergraduate working on his optical engineering degree.
Received on Fri 23 Feb 2007 02:36:00 AM PST