Almost 40 years to the day after the Apollo 17 crew snapped
the famed "blue marble" image of Earth floating in space on Dec. 7, 1972, NASA
has unveiled "black marble" video views of the planet by night.
The cloud-free pictures, taken with a high-resolution visible and
infrared imager aboard a NASA and National Oceanic and Atmospheric
Administration satellite, capture the night lights of Earth in unprecedented
detail.
The sensor can capture the equivalent of three low-light images
simultaneously, giving researchers the opportunity to study Earth's
atmosphere, land and oceans at night, Reuters reported.
"It's very high-quality data," NOAA scientist Christopher Elvidge told
reporters at the American Geophysical Union conference in San Francisco.
"I rate it six times better spatial resolution."
The so-called day-night band of the Visible Infrared Imaging Radiometer
Suite, or VIIRS, can distinguish the night-time glow of Earth's atmosphere as
well as a light from a single ship at sea. The resolution is far sharper than
what has been available previously.
VIIRS is aboard the Suomi NPP satellite, which orbits about 800 km above
Earth's poles.
Scientists used the day-night sensor to watch the superstorm Sandy,
illuminated by moonlight, hit the New Jersey shore on Oct. 29. It also
captured the power outages that plunged the area into darkness as the storm
tore into populated areas.
The National Weather Service is starting to use the VIIRS day-night
sensor to forecast fog in coastal regions, including San Francisco.
Some VIIRS images have surprised scientists. The sensor, for example,
captured light from the upper atmosphere illuminating clouds and ice in
visible wavelengths -- by night.
Distributed by MCT Information Services
