Landsat 8's First Year
On Feb. 11, 2013, the Landsat 8 satellite rocketed into a sunny California
morning onboard a powerful Atlas V and began its life in orbit. In the year
since launch, scientists have been working to understand the information the
satellite has been sending back. Some have been calibrating the data—checking it
against ground observations and matching it to the rest of the 42-year-long
Landsat record. At the same time, the broader science community has been
learning to use the new data.
The map above—one of the first complete views of the United States from
Landsat 8—is an example of how scientists are testing Landsat 8 data. David Roy,
a co-leader of the USGS-NASA Landsat science team and researcher at South Dakota
State University, made the map with observations taken during August 2013 by the
satellite’s Operational Land Imager.
The strips in the image above are a result of the way Landsat 8 operates.
Like its predecessors, Landsat 8 collects data in 185-kilometer (115-mile) wide
strips called swaths or paths. Each orbit follows a predetermined ground track
so that the same path is imaged each time an orbit is repeated. It takes 233
paths and 16 days to cover all of the land on Earth. This means that every land
surface has the potential to be imaged once every 16 days, giving Roy two or
three opportunities to get a cloud-free view of each pixel in the United States
in a month.
Image Credit: NASA/David Roy
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
No hay comentarios:
Publicar un comentario