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Landsat 8 Acquires First image : LDCM successful

by Santosh Sharma

As we discussed in our previous post Landsat Data Continuity Mission is the latest workhorse after Landsat EMT+. It was launched on 11th February 2013 from Vandenberg Air Force Base in California.  Landsat 8 has the ability to capture a 185 km swath of Earth and is meant to provide a regional and national scale view of our planet with a full picture of the planet’s surface every 16 days.

Turning on the new satellite instruments the Landsat Data Continuity Mission (LDCM) captured its first images of Earth  at 1:40 p.m. EDT on March 18. This first image shows the meeting of the Great Plains of the USA with the Front Ranges of the Rocky Mountains in Wyoming and Colorado. The natural-color image shows the green coniferous forest of the mountains merging with relative less vegetated brown plains. The cities of Cheyenne, Fort Collins, Loveland, Longmont, Boulder and Denver can be seen from north to south.

First image acquired by Landsat Data Continuity Mission(LDCM) showing Fort Collins area and the Horsetooth Reservoir. Courtesy: USGS/NASA Earth Observatory

Above  natural color image showsthe landscape in the colors our eyes would see, but LDCM sensors also have the ability to see wavelengths of light that our eyes cannot see. LDCM captures eleven spectral 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.

Below is the image of the same area with a different band combination:  3 (green), 5 (near infrared), and 7 (short wave infrared 2):

False Color image from LDCM of Fort Collins area showing dark wildfire burn scar from the Galena Fire visible just to the left of the Horsetooth reservoir. Courtesy: USGS/NASA Earth Observatory

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. Below is the Black & White image showing the temperature variations in the area:

This is black-and-white LDCM scene from the first TIRS thermal infrared band. Warmer surfaces appear light gray to white in the thermal image while cooler areas appear dark gray to black. Clouds in the colder upper atmosphere, for instance, appear black against the lighter background of the warmer ground surface. Courtesy: USGS/NASA Earth Observatory

 

Below diagram illustrates how LDCM’s observations at different wavelengths are combined to create one image.

Credit: NASA’s Goddard Space Flight Center

LDCM’s different bands

Download(32mb) the first LDCM scene in natural color captured on March 18, 2013, the first day that OLI observed Earth from space.


SATPALDA is a privately owned company and a leading provider of satellite imagery and GeoSpatial services to the user community. Established in 2002, SATPALDA has successfully completed wide range of photogrammetric and Remote Sensing Projects.

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