There is a new crack in Antarctica's icy armor. The earliest stages of
the formation of a massive iceberg was captured by NASA's Landsat 7
satellite on January 4, 2001. As is evident in this pair of Landsat 7
images, there was no crack in the March 2000 scene, but by January the
crack had grown to more than 25 km (15) miles long, stretching more than
two-thirds of the way across the Pine Island Glacier.
According to NASA Glaciologist Robert Bindschadler, most of this crack
formed very rapidly, in less than five weeks. Currently, the crack is
growing much more slowly, at about 13 meters (40 feet) a day.
Bindschadler's prediction is that the crack will result in the calving
of a major iceberg in probably less than 18 months.
Landsat 7, a cooperative mission between NASA and the United States
Geological Survey, Reston, Virginia, completed its second annual
continent-wide mapping of Antarctica last month. With its capability to
see features as small as 15 meters (50 feet) across, Landsat 7 provides
the most detailed observations available of the remote continent, many
parts of which have never been mapped at this resolution before. Landsat
7 passes over the continent 16 times a day in its nearly pole-to-pole
orbit, taking an average of 300 images each week during the Antarctic
summer (November to February) when the surface is best illuminated with