Russian researchers are studying images taken by the
crew of the International Space Station to better understand
the catastrophic glacier collapse and landslide that
occurred on the northern slope of Mount Kazbek in September
— information that may help us better understand our home
planet.
On Sept. 20, 2002, the collapse of a hanging glacier on the
slope of Mount Dzhimarai-Khokh onto the Kolka glacier on
Mount Kazbek triggered an avalanche of ice and debris that
buried several small villages in the Russian Republic of
North Ossetia. The avalanche killed dozens of people.
Glacial debris dammed rivers and formed several lakes. One
of these lakes flooded a village, and others are threatening
to burst their new banks and form debris flows downstream.
Russian scientists at Moscow State University are using
images taken by the crew aboard the Station to measure small
changes near the glacier. “We can see a slight increase in
the area of a new lake near the Kolka Glacier terminus,”
said Dr. Olga Tutubalina, a scientist at Moscow State
University. “We first sighted this lake during our field
trip on Oct. 5, and the lake surface has increased from Oct.
6 to 19. It is potentially dangerous, because it can produce
disastrous outburst mudflows,” she said.
The Russian investigators also include Moscow State
University scientists Dr. Dmitry Petrakov, Dr. Victor
Popovnin and Sergei Chernomorets. The Russian Foundation for
Basic Research supports their activities. In September 2001,
the team visited the Kolka Glacier to assess its state.
After the recent collapse, the team conducted an analysis of
images taken by the Station crew and then organized another
field trip to gather additional information. They plan to
continue monitoring the area using both satellite images and
astronaut photography.
Dr. Lev Dessinov, of the Russian Academy of Sciences,
collaborated with scientists at NASA’s Johnson Space Center,
Houston, to establish global glacier sites as a research
topic for the Crew Earth Observations project. Dessinov was
also part of the team of scientists called to the Kolka area
immediately after the glacier collapsed. “We collected a lot
of information and [NASA astronaut photographs] were one of
our main data sources,” Dessinov said.
The Expedition 5 crew, Commander Valery Korzun, Flight
Engineer Sergei Treschev and NASA Station Science Officer
Peggy Whitson, have been photographing this area since the
beginning of the mission in June as part of the Russian
URAGAN and U.S. Crew Earth Observations projects, which are
studying changes in the world’s glaciers. On Aug. 13, about
one month before the glacier collapsed, the crew
photographed the mountain. Although scientists have
predicted the possibility of large glacial collapses, at the
time of the first image, no one predicted that tragedy would
strike the mountain village of Karmadon a little more than a
month later. On a visit to the Station, Shuttle crewmembers
photographed the aftermath of the collapse on Oct. 17.
Station crewmembers then took a spectacular three-
dimensional oblique image on Oct. 19.
The crew has been able to provide international scientists
with images, such as those taken for the glacier
researchers, by using motion compensation techniques
developed by previous Station crews. Crewmembers can use
high-magnification lenses to survey features around the
world from their relatively low orbit, obtaining spatial
resolutions as good as six meters. This means scientists can
use photographs taken from the Station to study changes that
are occurring in very small features on the Earth’s surface.
These images can augment satellite data, especially when
astronauts take advantage of varying Sun angles on the
landscape to capture three-dimensional views. This
technique, which was used to take a photo of the glacier
area on Oct. 19, provides imagery that is both visually
spectacular and easy to interpret.
“The (Oct. 19) image gives us a rare opportunity to try and
estimate the volume of the initial glacier collapse,” said
Chernomorets.
The first five Space Station crews have taken more than
41,000 images of the Earth using digital still cameras, 35
mm cameras, 70 mm cameras and a variety of lenses.
Crewmembers are able to produce higher-resolution
photographs with the high-magnification lenses by learning
to compensate for the relative motion of the Earth below
them as they point their cameras through a specially built
window in the Station’s Destiny laboratory.
The photographs of the Kolka glacier are on the Internet at:
http://www.jsc.nasa.gov/images/eol/kolka.html
A searchable database containing more than 35 years of
astronaut photography is also available at:
http://eol.jsc.nasa.gov/sseop>/a>