Turning on new satellite instruments is like opening new eyes. The Landsat Data Continuity Mission (LDCM) released its first images of Earth, collected at 1:40 p.m. EDT on March 18. The first image shows the meeting of the Great Plains with the Front Ranges of the Rocky Mountains in Wyoming and Colorado. The natural-color image shows the green coniferous forest of the mountains coming down to the dormant brown plains. The cities of Cheyenne, Fort Collins, Loveland, Longmont, Boulder and Denver string out from north to south. Popcorn clouds dot the plains while more complete cloud cover obscures the mountains.
LDCM is a joint mission of NASA and the Department of Interior’s U.S. Geological Survey.
“It’s a really great day,” said Jeff Pedelty, an instrument scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., who worked on the LDCM Operational Land Imager, or OLI instrument, that took the natural color image. He’s very impressed with the level of detail they can see with the advancements to the sensor. “It’s wonderful to see, there’s no doubt about it, and it’s a relief to know that this is going to work wonderfully in orbit.”
The natural color image showed the landscape in the colors our eyes would see, but Landsat sensors also have the ability to see wavelengths of light that our eyes cannot see. LDCM sees eleven bands within the electromagnetic spectrum, the range of wavelengths of light. OLI collects light reflected from Earth’s surface in nine of these bands. Wavelengths on the shorter side include the visible blue, green, and red bands. Wavelengths on the longer side include the near infrared and shortwave infrared.
LDCM’s second instrument, the Thermal Infrared Sensor (TIRS) detects light emitted from the surface in two even longer wavelengths called the thermal infrared. The intensity of the emitted light at the longer wavelengths measured by TIRS is a function of surface temperature. In the black-and-white image of the first thermal band on TIRS, warmer areas on the surface are brighter while cooler areas are dark.
The first thermal images seen by Dennis Reuter, TIRS instrument scientist at Goddard, were forwarded to him from the data processors. “To say it was exciting was an understatement,” said Reuter, who was blown away by the data quality. “Wow! This is beautiful!” he wrote in an email. “Look at those amazing clouds! And the detail!”
Clouds in the colder upper atmosphere stand out as black in stark contrast to a warmer ground surface background. The TIRS images were collected at exactly the same time and place as the OLI data, so all eleven bands can be used together.
The infrared bands on both TIRS and OLI complement the visible bands, said Reuter. “You’re seeing things in the visible that you don’t necessarily see in the infrared, and vice versa,” he said.
Source:
ISDE Blog 
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