This means that every area of land on Earth is imaged at least once every 16 days.
The satellite orbits at an altitude of 705 kilometers above the Earth in a near polar orbit (around the Earth from North Pole to South Pole). It is sun-synchronous which means that the satellite always passes the same point on Earth at the same local time.
If you live near the equator Landsat 8 will pass high above your head at 10:00 AM in the morning every 16th day to image your neighbourhood. Watch the FarEarth Observer to see what Landsat sees live!
The satellite takes images of the Earth below and streams it down to the station in real-time.
The station's antenna points toward the satellite and tracks it for as long as it can until it moves out of range. Each station therefore receives the images of the areas around it. This is called the station's coverage circle and you can see it drawn on the map in the FarEarth Observer.
Landsat 8 has a pushbroom sensor which means that it scans the Earth line by line, 185 kilometers wide. It continuously transmits data to the station antenna down below where it is decoded, processed and turned into images in real-time (yes, as fast as it is received!).
These images are streamed to the FarEarth Observer within seconds where you can view them in your browser. You see what Landsat sees!
It has two onboard sensors and can "see" 11 colours called spectral bands.
Humans can see colours between 390 and 700 nm.
Landsat's Operational Land Imager (OLI) sensor records 9 bands between 430 and 2300 nm, which means it can see colours ranging from blue to shortwave infrared. Each pixel has a resolution of 30 by 30 meters, except for the panchromatic band with a resolution of 15 meters.
The Thermal Infrared Sensor (TIRS) has two bands in the long wave infrared spectrum between 10300 and 12500 nm. These pixels have a resolution of 100 by 100 meters.
Different colour bands can be combined to highlight different features.
The two images to the left show the same area in Australia with a river and salt pan.
The first image shows the area the way a human would see it. We combined Landsat's red, green and blue bands to make the image.
For the second image we added some of the "invisible" bands. What looks like red in the picture is actually shortwave infrared. Green is really near infrared and what looks like blue is actually red! See how the plants stand out in the green (actually near infrared)?
These two images show a forest fire next to a lake.
The image on the left is how a human would see it. See the smoke?
The image on the right shows the same area but this time the red and green in the picture are actually shortwave infrared, and blue remains blue. See how the orange fires become visible through the smoke? X-ray vision!