NASA LANDSAT-5 (LDCM) satellite takes the Salton Sea's temperature

The Salton Sea in Southern California and nearby irrigated fields stand out in this image taken March 24, 2013, by the Thermal Infrared Sensor (TIRS) instrument on the Landsat Data Continuity Mission (LDCM) satellite. 

Darker areas of the image are cooler, while lighter areas are warmer. 

Credit: USGS/NASA's Earth Observatory.

An image from an instrument aboard NASA's Landsat Data Continuity Mission or LDCM satellite may look like a typical black-and-white image of a dramatic landscape, but it tells a story of temperature.

The dark waters of the Salton Sea pop in the middle of the Southern California desert. Crops create a checkerboard pattern stretching south to the Mexican border.

If you looked at the Salton Sea in person, your eyes would not see anything presented in the LDCM image.

Instead of showing visible light, the image shows the amount of heat, or thermal energy, radiating from the landscape and detected by the Thermal Infrared Sensor, or TIRS, instrument on LDCM. Cooler areas are dark, while warm areas are bright.

The dark squares in the LDCM's image of the Salton Sea are fields where plants can absorb irrigation water before sweating it off through a process called transpiration.

Just like when people sweat, plants cool down when they transpire.

The combination of transpiration and water evaporating from the ground itself, evapotranspiration, drops the temperature of the irrigated land.

Those cool temperatures, indicating healthy, well-watered plants, are picked up by TIRS.

Dennis Reuter

"What you're looking at is infrared light that's generated by the Earth itself," said Dennis Reuter, TIRS instrument scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.

TIRS is one of two instruments on the newest spacecraft in the Landsat family, launched Feb. 11 and currently in its on-orbit calibration and checkout phase.

While its partner instrument records reflected sunlight, TIRS complements that view with temperature readings across swaths of Earth's surface.

The Goddard-designed detectors in the TIRS instruments can pick up two different bands of thermal infrared energy, which excite electrons and create an electrical signal.

With TIRS measuring the strength of those signals, corresponding to temperatures on the ground, scientists can generate images like this one of the Salton Sea.

The view you get from TIRS is similar to what you've seen on television crime shows when cops use thermal imagers to track warm-bodied suspects moving around inside of a building. With Landsat, though, scientists use the thermal bands to track down water.

Dark pixels representing cool spots and light pixels of hot spots are key to helping water managers determine where the valuable resource is being used for irrigation, especially in the arid western United States.

NASA, USGS release first Landsat 8 images

The area around Boulder, Colo., is shown here in a true colour image collected by the OLI aboard LDCM on March 18, 2013. 

The OLI and an important component of TIRS, its cryocooler, were built at the Ball Aerospace & Technologies Corporation facility in Boulder. 

Credit: USGS/NASA Earth Observatory

NASA and the Department of the Interior's U.S. Geological Survey (USGS) have released the first images from the Landsat Data Continuity Mission (LDCM) satellite, which was launched Feb. 11.

The natural-colour images show the intersection of the United States Great Plains and the Front Range of the Rocky Mountains in Wyoming and Colorado.

In the images, green coniferous forests in the mountains stretch down to the brown plains with Denver and other cities strung south to north.

"We are very excited about this first collection of simultaneous imagery," said Jim Irons, LDCM project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.

"These images confirm we have two healthy, functioning sensors that survived the rigors of launch and insertion into Earth orbit."

Since launch, LDCM has been going through on-orbit testing.

The mission operations team has completed its review of all major spacecraft and instrument subsystems, and performed multiple spacecraft attitude maneuvers to verify the ability to accurately point the instruments.

The two LDCM sensors collect data simultaneously over the same ground path. OLI collects light reflected off the surface of Earth in nine different regions of the electromagnetic spectrum, including bands of visible light and near-infrared and short-wave-infrared bands, which are beyond human vision.

TIRS collects data at two longer wavelength thermal infrared bands that measure heat emitted from the surface.

By looking at different band combinations, scientists can distinguish features on the land surface.

These features include forests and how they respond to natural and human-caused disturbances, and the health of agricultural crops and how much water they use.

Data from LDCM will extend a continuous, 40-year-long data record of Earth's surface from previous Landsat satellites, an unmatched, impartial perspective that allows scientists to study how landscapes all across the world change through time.

The natural-colour images were processed by the EROS Data Center north of Sioux Falls.

"These first scenes from the new Landsat satellite continue the remarkable output from the Landsat program with better, more useful imagery and information," said Matthew C. Larsen, associate director for climate and land use change at the U.S. Geological Survey in Reston, Va.

"We are gratified that this productive partnership between USGS and NASA has maintained the continuity and utility of this essential satellite tool, providing the foundation for land and water management around the globe."

As planned, LDCM currently is flying in an orbit slightly lower than its operational orbit of 438 miles (705 kilometers) above Earth's surface.

As the spacecraft's thrusters raise its orbit, the NASA-USGS team will take the opportunity to collect imagery while LDCM is flying under Landsat 7, also operating in orbit.

Measurements collected simultaneously from both satellites will allow the team to cross-calibrate the LDCM sensors with Landsat 7's Enhanced Thematic Mapper-Plus instrument.

"So far, our checkout activities have gone extremely well," said Ken Schwer, LDCM project manager at Goddard.

"The mission operations team has done a tremendous job getting us to the point of imaging Earth." During the next few weeks, this team will calibrate the instruments and verify they meet performance specifications.

After its checkout and commissioning phase is complete, LDCM will begin its normal operations in May. At that time, NASA will hand over control of the satellite to the USGS, which will operate it throughout its planned five-year mission life.

The satellite will be renamed Landsat 8. USGS will process data from OLI and TIRS and add it to the Landsat Data Archive at the USGS Earth Resources Observation and Science Center, where it will be distributed for free via the Internet.

For more information on these first LDCM images

For more information on the LDCM mission.

NASA's Landsat Data Continuity Mission (LDCM) satellite in payload fairing

Technicians encapsulate NASA's Landsat Data Continuity Mission (LDCM) satellite in its payload fairing in the Astrotech processing facility at Vandenberg Air Force Base in California.

The Landsat Data Continuity Mission (LDCM) is NASA's eighth satellite in the Landsat series and continues the Landsat program's critical role in monitoring, understanding and managing the resources needed for human sustainment such as food, water and forests. 

As our population surpasses seven billion people, the impact of human society on the planet will increase, and Landsat monitors those impacts as well as environmental changes.

Image credit: NASA/VAFB

Eighth Landsat LDCM Satellite Arrives At Launch Site

An oversized semi-trailer truck carrying NASA's Landsat Data Continuity Mission (LDCM) has arrived at its launch site at Vandenberg Air Force Base in California in preparation for launch. 

This NASA and U.S. Geological Survey mission will continue a 40-year record of measuring change on the planet from space.

LDCM is the eighth satellite in the Landsat series, which began in 1972. It will extend and expand global land observations that are critical in many sectors, including energy and water management, forest monitoring, human and environmental health, urban planning, disaster recovery and agriculture.

Following final tests, the LDCM satellite will be attached to an Atlas V rocket and launched into space Feb. 11, 2013. Built and tested by Orbital Sciences Corp., LDCM left their Gilbert, Ariz., facility on Dec. 17.

"LDCM builds on and strengthens a key American resource: a decades-long, unbroken Landsat-gathered record of our planet's natural resources, particularly its food, water and forests," said Jim Irons, Landsat project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md.

LDCM carries two instruments, the Operational Land Imager (OLI) built by Ball Aerospace and Technologies Corp. in Boulder, Colo., and the Thermal Infrared Sensor (TIRS) built by NASA Goddard.

"Both of these instruments have evolutionary advances that make them the most advanced Landsat instruments to date and are designed to improve performance and reliability to improve observations of the global land surface," said Ken Schwer, LDCM project manager at NASA Goddard.

OLI will continue observations in the visible, near infrared, and shortwave infrared portions of the electromagnetic spectrum and includes two new spectral bands, one of which is designed to support monitoring of coastal waters and the other to detect previously hard to see cirrus clouds that can otherwise unknowingly impact the signal from the Earth's surface in the other spectral bands.

TIRS will collect data in two thermal bands and will thus be able to measure the temperature of the Earth's surface, a measurement that's vital to monitoring water consumption, especially in the arid western United States.