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OLI (Operational Land Imager) article edits, adding overview of OLI and the mission it's helping with along with expanding on its specifications and design.

Overview and Mission
OLI currently operates alongside TIRS (Thermal Infrared Sensor) onboard the LDCM. The build and design of OLI differs from previous generations of instruments, while still maintaining data continuity with archived Landsat data from the last 40 years by keeping the same spectral and spatial resolutions of previous instruments.

OLI currently aids the Landsat-8 mission in the imaging of Earth's surface and the collection of moderate resolution data that is used to monitor changing trends on the surface and evaluate how land usage changes over time. The images and data that OLI has helped collect have practical applications today in agriculture, mapping, and monitoring changes in snow, ice, and water.

Specifications and Design
OLI is a pushbroom sensor that operates in the visible (VIS) and short wave infrared (SWIR) spectral regions. It has a swath width of 115 miles (185 km), which means it can image the entire Earth over a repeating cycle of 16 days. OLI uses nine channels, which range from wavelengths of 443 nm to 2200 nm. Of these nine channels, eight are multispectral and one is panchromatic. The eight multispectral channels have a 98-foot (30 meter) spatial resolution, and the panchromatic channel has a spatial resolution of 49 feet (15 meters).

While the spectral and spatial resolution of OLI’s channels were kept the same as prior instruments in order to maintain data continuity with the entire Landsat archive, two spectral bands, (the first a blue visible channel and the second an infrared channel) were added. These bands were designated as band 1 and band 9, and serve as an enhancement from previous instruments, which lacked these channels. Band 1 was created to locate and determine water resources and investigate coastal areas, and band 9 serves a unique purpose of detecting cirrus clouds.