Untitled Document
NASA/JPL/NIMA
There are things about Earth
we never see, because the human eye is so darn limited. Spacecraft can help.
In this picture of an interesting place on Earth, we benefit from the elevated
perspective of space and the ability of cameras that detect wavelengths of light
outside the optical range.
The composite and rather
fantastical rendering shows a complex glacial structure, called a Piedmont,
in southeastern Alaska. Piedmont glaciers occur where mountain glaciers fan
out into the lowlands. This one, named the Malaspina Glacier, is also the site
of many mergers.
The Agassiz Glacier (left)
and Seward Glacier (right) are the two primary feeders of the Malaspina complex,
which is about 40 miles (65 kilometers) wide and travels 28 miles (45 kilometers
from the front of the mountains to the sea.
The image was created by
combining visible and infrared data from a Landsat satellite with an elevation
model created by the Shuttle Radar Topography Mission. Glacial ice is light
blue; snow is white; plants are green; rock is gray or tan. The ocean, in front,
is blue. The sky is fake.
The crinkly features result
from rock that's carried downslope and deposited at the edges of the melting
ice to form long piles, called moraines.
-- Robert
Roy Britt
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