A Giant Among Earth Satellites
 
Sept. 24, 2014: The International Space Station has been called a stepping
stone to other worlds.
 
NASA hasn't forgotten, however, that the behemoth space station is also on the
doorstep of Earth.
 
"We're seeing the space station come into its own as an Earth-observing
platform," says Julie Robinson, chief scientist for the International Space
Station Program. "It has a different orbit than other Earth-observing
satellites. It's closer to Earth, and it sees Earth at different times of day
with a different schedule."
 
http://www.youtube.com/watch?v=jn8yezfH7HM&feature=youtu.be
 
A new ScienceCast video explains how the International Space Station has
become the largest of all Earth-observing satellites. Play it
 
In short, the space station offers something unique to the study of our home
planet.
 
Sometimes astronauts in low Earth orbit to see what regular satellites do
not.  In May 2013 for example, astronauts on board the International Space
Station photographed a fresh eruption of the Pavlof Volcano in the Aleutian
Islands. Their oblique perspective revealed the three dimensional structure of
the ash plume, which was only 20,000 feet high, but many times longer.
Down-looking satellites could not get the same kind of 3D information.
 
Low Earth orbit turns out to be a great place to study the planet below. In
recent years astronauts trained to photograph Earth have gathered data on
desert dust, coral reefs, urban growth, pollution, glaciers, hurricanes,
lightning, river deltas, volcanic plumes, Northern and Southern Lights and
much more.
 
Now, however, NASA is taking the space station's Earth-observing capabilities
to a whole new level. Before the end of the decade, six NASA Earth science
instruments will be mounted to the station to help scientists study our
changing planet.
 
The upgrades began this month: On Sept. 20th, a SpaceX resupply rocket blasted
off from Cape Canaveral carrying the first NASA Earth-observing instrument to
be mounted on the exterior of the space station: ISS-RapidScat will monitor
ocean winds for climate research, weather predictions and hurricane science.
 
http://www.nasa.gov/multimedia/imagegallery/image_feature_2515.html
 
Learn more about ISS observations of the erupting Pavlof volcanoNext up is the
Cloud-Aerosol Transport System--"CATS' for short--a laser radar that can
measure clouds along with airborne particles such as pollution, mineral dust,
and smoke. CATS will follow ISS-RapidScat on another SpaceX flight targeted
for December.
 
Two more Earth science instruments are slated to launch in 2016. First, SAGE
III will measure ozone and other gases in the upper atmosphere to help
scientists assess how the ozone layer is recovering. Second, the Lightning
Imaging Sensor will monitor thunderstorm activity around the globe.
 
Those instruments are already built and ready to fly.  In July, NASA selected
proposals for two new instruments: The Global Ecosystem Dynamics
Investigation, "GEDI", and the ECOsystem Spaceborne Thermal Radiometer
Experiment on Space Station, "ECOSTRESS", will give scientists new ways to
observe how forests and ecosystems are affected by climate change. Both will
be completed before the end of the decade.
 
Stephen Volz, associate director of flight programs in the Earth Science
Division at NASA Headquarters explains the rapid pace of new sensors: "With
the space station we don't have to build a whole new spacecraft to gather new
data -- it's already there. Designing instruments for the space station also
gives us a chance to do high-risk, high-return instruments in a relatively
economical way."
 
The biggest spacecraft in Earth orbit is now paying serious attention to our
home planet.  For more news from low-Earth orbit, stay tuned to 
cience.nasa.gov
 
Credits:
Author: Dr. Tony Phillips |  Production editor: Dr. Tony Phillips | Credit:
Science@NASA
 
More information about ISS Earth Science Instruments
 
ISS-Rapidscat
 
Cloud-Aerosol Transport System
 
Global Ecosystem Dynamics Investigation
 
SAGE III
 
 
Regards,
 
Roger

--- D'Bridge 3.99
 * Origin: NCS BBS - Houma, LoUiSiAna (1:3828/7)