NASA Science News for April 21, 1999:

1. Every day is Earth Day for climate scientists - Scientists at the Global Hydrology and Climate Center are stepping back to get a closer view of terra firma. They plan to use image from Landsat 7, launching later this year, combined with other data to better understand the phenomenon of urban heat islands.

2. Students to learn what's hot at Earth Day celebration - Open house at Global Hydrology and Climate Center on April 22 will have 5th graders learning from 2nd graders and everyone learning something new about planet Earth.


NASA Headquarters, Washington, DC
U.S. Geological Survey, Reston, VA

April 21, 1999

NASA AND USGS TO UNVEIL FIRST LANDSAT 7 IMAGE ON EARTH DAY

NASA and the U.S. Geological Survey will unveil the first Landsat 7 image on Earth Day, April 22, opening a new era in the study of our home planet.

Dr. Ghassem Asrar, NASA Associate Administrator for the Office of Earth Science, Washington, DC, and Dr. Bonnie McGregor, Associate Director of the U.S. Geological Survey, Reston, VA, will unveil the image. Due to a scheduling conflict, NASA Administrator Daniel S. Goldin will be unable to unveil the image as previously announced.

The resolution of the new image is twice as good as previous Landsat images, distinctly highlighting airport runways, dams, cities, rivers and highways.

The image unveiling is part of NASA's Earth Day and Take Our Daughters (and Sons) to Work Day activities, which will take place at 10:30 a.m. EDT in the James E. Webb Memorial Auditorium, in the west lobby of NASA Headquarters, 300 E Street SW, Washington, DC. Media are invited to attend.

Landsat 7, launched April 15, is the latest in a series that began with Landsat 1 in 1972. The satellite is gathering data from Earth's land surface and surrounding coastal regions. Analysis of the data will provide scientists with new information on deforestation, receding glaciers and crop monitoring. After on- orbit testing, NASA will turn the satellite over to the Geological Survey to manage.


More information about NASA's Earth Science program

Landsat 7 Integration & Test Images, March 1999 to Launch.


A 32-page PDF version of Landsat 7 launch press kit (approx. 374 KB).

Articles on using Landsat images to document environmental changes.


Lockheed Martin Missiles & Space
April 9, 1999

LOCKHEED MARTIN LANDSAT-7 SPACECRAFT READY FOR LAUNCH

SUNNYVALE, Calif., April 9, 1999 -- The Landsat-7 spacecraft, built at the Lockheed Martin Missiles & Space facility in Valley Forge, PA, is being prepared for launch by the National Aeronautics and Space Administration at Vandenberg Air Force Base, Calif. Liftoff is scheduled for April 15, 1999.

"We're very pleased to have completed work on the Landsat-7 spacecraft and have it here at Vandenberg in preparation for launch," said Bob LeRoy, Landsat-7 program manager at Lockheed Martin Missiles & Space. "Our Delaware Valley employees have built all of the Landsat spacecraft since the beginning of the program in 1972. It is because of their dedication and pride that this program has been so successful."

The science instrument on Landsat-7, the Enhanced Thematic Mapper Plus (ETM Plus), designed and built by Raytheon Santa Barbara Remote Sensing, Santa Barbara, Calif., will continue a database of high-resolution Earth imagery begun in 1982 by the Landsat-4 thematic mapper. As changes occur on the Earth's surface due to natural or human-induced events, scientists will be able to use the archive of imagery from the Landsat missions to better understand the behavior of the global environment. Applications for Landsat-7 imagery will include agricultural crop planning, timber issues in the Northwest, and information about population change and water quality.

Landsat-7 will add to the global archive of sunlit, substantially cloud-free images of the Earth's land surfaces. The spacecraft contains several technological improvements over previous Landsat satellites and their instruments. These improvements include better instrument calibration and a solid-state data recorder capable of storing 100 individual ETM Plus Earth images. This capability will enable Landsat-7 to update a complete global view of the Earth's land surfaces seasonally or approximately four times per year.

In 1975, NASA Administrator Dr. James Fletcher stated that if one space age development might save the world, it would be Landsat and its successor satellites. Since the first launch on July 23, 1972, Landsat satellites have continuously supplied land surface images of the globe.

Landsat's 27-year collection of land images serves those who observe and study the Earth, those who manage and utilize its natural resources, and those who monitor the changes brought on by natural processes and human activities. The images provide information applicable to the broad and diverse needs of business, science, education, and government. The data from Landsat spacecraft constitutes the longest, relatively high spatial resolution, multispectral record of Earth's continental surfaces as seen from space. The record is unmatched in quality, detail, coverage, and value.

Landsat is the central pillar of the national remote sensing capability. The Landsat-7 spacecraft was built to complement the research of NASA's Earth Science Enterprise, a long-term research program designed to study Earth's land, oceans, atmosphere, ice and life as a total integrated system. NASA's Goddard Space Flight Center manages the development of Landsat for the Earth Science enterprise, NASA Headquarters, Washington, D.C.

Lockheed Martin Missiles & Space, based in Sunnyvale, Calif., is a leading supplier of satellites and space systems to military, civil government and commercial communications organizations around the world. These spacecraft and systems have enhanced military and commercial communications; provided new and timely remote-sensing information; and furnished new data for thousands of scientists studying our planet and the universe.

High and low resolution images of the Landsat-7 spacecraft are available for downloading at the following URL:

http://www.lmsw.external.lmco.com/photos/civil_space/landsat/landsat.html

Photo Credit: Russ Underwood, Lockheed Martin Missiles & Space

See also a collection of Landsat images at NASA Goddard Space Flight Center:
http://svs.gsfc.nasa.gov/imagewall/LandSat/


Goddard Space Flight Center
Greenbelt, MD

March 1999

LANDSAT 7 SPACECRAFT TO JOIN NASA'S EARTH SCIENCE TEAM

NASA will deploy the first major satellite in an unprecedented program to check the health of Planet Earth and understand the complex interactions that drive global change with the April 15 launch of the Landsat 7, the latest mission in the Landsat series, which has been documenting the Earth's surface for more than a quarter century.

NASA plans to launch six spacecraft over the course of the year dedicated to advancing our understanding of global change. Landsat 7's role in this effort will be to make global, high-resolution measurements of land surface and surrounding coastal regions.

The diversity of applications makes the Landsat spacecraft unique among Earth observation satellites. Landsat images have been used in everything from measuring the ebb and flow of glaciers and population changes in and around metropolitan areas, to monitoring strip mining reclamation and assessing water quality in lakes. Landsat has been used to monitor timber losses in the U.S. Pacific Northwest, map the extent of winter snow pack, and measure forest cover at the state level.

"We feel that the Landsat 7 spacecraft will dramatically enhance the use of remotely sensed data in our daily lives," said Dr. Darrel Williams, Landsat 7 Project Scientist, at NASA's Goddard Space Flight Center, Greenbelt, Md.

Every 16 days, Landsat 7 will fly over and document the condition of the entire globe. As far as scientific Earth observing satellites go, Landsat 7 is unique in that the images it collects are extremely detailed -- Landsat can "see" features on the planet as small as 30 meters, compared to the geostationary GOES satellites which can only resolve objects of 4 kilometers or greater. So good are the Landsat images that scientists studying volcanoes can actually produce maps of lava flows with pinpoint accuracy.

Landsat 7 marks a new direction in the program to reduce the cost of data and increase global coverage for use in global change research. Every day, Landsat 7 will collect 250 scenes, each one containing enough digital data to fill a powerful home computer's hard drive. While previous Landsat data were often too expensive for widespread scientific use, all Landsat 7 data received at the main collecting center in Sioux Falls, South Dakota will be archived and available electronically within 24 hours and will be sold at cost.

Scientists use Landsat satellites for some very down-to-earth purposes.

Urban sprawl is one example. Observing urban areas over time with Landsat imagery can show where growth is taking place and help geographers evaluate how different urban planning programs effect population growth and land use. One of Landsat's 14 scientific teams will use Landsat observations to evaluate growth patterns of cities such as Portland, Ore. (which has strict planning and environmentally sensitive zoning laws) with other cities around the world.

Another group of scientists led by the Department of Agriculture want to use Landsat 7 data to improve on a program to help farmers and land managers increase crop yields and cut costs while reducing environmental pollution.

Scientists from NASA's partner agency in the Landsat 7 mission, the U.S. Geological Survey, want to use Landsat 7 to spot the amount and condition of dry biomass on the ground, which are potential sources for feeding wildfires that can threaten humans, animals and natural resources.

Landsat 7 is scheduled to launch on April 15, 1999 from Vandenberg Air Force Base, CA. The two-minute launch window opens at 11:32 a.m. Pacific Daylight Time.

Landsat 7 will be launched on a Delta-II expendable launch vehicle. Separation of the spacecraft from its launch vehicle will occur about 62 minutes after launch. Once in its final orbital position, the satellite will orbit the Earth at an altitude of approximately 438 miles (705 kilometers) with a Sun-synchronous 98-degree inclination and a descending equatorial crossing time of 10 a.m. The orbit will be adjusted so that it covers the complete Earth every 16 days. This orbit will be maintained with periodic adjustments during the 5-year life of the mission.

The instrument onboard Landsat 7 is the Enhanced Thematic Mapper Plus (ETM+). The instrument is a passive sensor, a type of remote-sensing instrument that measures solar radiation reflected or emitted by the Earth.

The instrument has eight bands sensitive to different wavelengths of visible and infrared radiation. It's improved from earlier versions. Landsat 7's Thematic Mapper has better resolution in the thermal infrared band than the instruments carried by Landsats 4 and 5. It is also far more accurate than its predecessors.

The Landsat 7 system will collect and archive an unprecedented quantity of high-quality multispectral data each day. The data will, for the first time, provide a high-resolution view of both seasonal and interannual changes in the terrestrial environment.

The USGS Earth Resources Observation Systems Data Center (EROS Data Center) in Sioux Falls, SD will process, archive, and distribute all U.S. Landsat data. The ground system at the data center in Sioux Falls, SD will be capable of capturing and processing 250 Landsat scenes per day delivering at least 100 of the scenes to users each day.

"The USGS is proud to assume added responsibility for the processing and distribution of Landsat data," said R.J. Thompson, Landsat Program Manager, U.S. Geological Survey. "The Landsat system, conceived originally within the Department of the Interior, is an important dimension of the USGS' role in providing information for science for a changing world."

The Landsat Project Office, located at Goddard, manages Landsat development for NASA's Office of Earth Science in Washington, DC. Goddard is responsible for the development and launch of the satellite, and the development of the ground operations system. Spacecraft operations will be performed at a Mission Operations Center at the Goddard and at the Earth Resources Observation Systems Data Center. Goddard will operate the spacecraft until Oct. 1, 2000, when this function is turned over to the U.S. Geological Survey.

The spacecraft was built by Lockheed Martin Missiles and Space in Valley Forge, PA. The instrument was built by Raytheon (formerly Hughes) Santa Barbara Remote Sensing in Santa Barbara, CA.

Landsat 7 is part of a global research program known as NASA's Earth Science Enterprise, a long-term program that is studying changes in Earth's global environment. The goal of the Earth Science Enterprise is to provide people a better understanding of natural environmental changes. Earth Science Enterprise data, which will be distributed to researchers worldwide at the cost of reproduction, is essential to people making informed decisions about their environment.


NASA Headquarters, Washington, DC
Goddard Space Flight Center, Greenbelt, MD

March 12, 1998

LANDSAT-7 LAUNCH DELAYED

The Landsat-7 Earth science spacecraft will not be launched in July 1998 as planned, due to necessary changes in the design of the electrical power supply hardware for the spacecraft's main instrument. A new target launch date will be set by NASA officials after completion of instrument thermal vacuum tests scheduled for this July.

During a series of instrument-level thermal vacuum tests beginning in December 1997, a power supply on the Enhanced Thematic Mapper Plus (ETM+) instrument failed twice. ETM+ is Landsat-7's only science instrument. As a result of the most recent failure in January, both internally redundant power supplies were returned to their manufacturer. Completion of vacuum testing will be delayed while the power supplies are being repaired, which will consequently delay the launch.

It is not possible to set a precise new date for the launch from Vandenberg Air Force Base, CA, at this time, according to project managers. NASA will now work with its launch contractor, Boeing, on moving the Landsat-7 launch to a mutually agreeable date.

"We're looking at several options in order to minimize the impact to the launch schedule," said Phil Sabelhaus, Landsat-7 project manager at NASA's Goddard Space Flight Center, Greenbelt, MD. "When we understand precisely why the power supply failed and how long it will take to fix the problem, we'll be able to ascertain the impact to the launch schedule."

The enhanced thermatic mapper was designed and built by Raytheon (formerly Hughes) Santa Barbara Remote Sensing, Santa Barbara, CA. The Landsat-7 spacecraft was built by Lockheed Martin Missiles and Space, with integration of the instrument and spacecraft conducted at the company's facility in Valley Forge, PA.

` Landsat-7 is the latest installment in a long history of land remote-sensing spacecraft, spanning over 25 years of multispectral imaging of the Earth's surface, starting with the launch of Landsat-1 in 1972. Landsat-5, launched in March 1984, is still transmitting images to several domestic and international ground stations worldwide.

In particular, the science instrument on Landsat-7 will continue a data base of high-resolution Earth imagery begun in 1982 by the Landsat-4 thematic mapper. As changes occur on the Earth's surface due to natural or human-induced events, scientists will be able to study these recent changes with the aid of the archive of similar imagery. Applications include agriculture, forestry and urban planning.

Landsat-7 will add to the global archive of sun-lit, substantially cloud-free images of the Earth's land surfaces. Approximately one-quarter of the Earth's landmass will be imaged every 16 days, with a emphasis on seasonal changes in vegetation.

Landsat-7 contains several technological improvements over previous Landsat satellites and their instruments. These improvements include better instrument calibration and a solid state data recorder capable of storing 100 individual enhanced thematic mapper images of the Earth. This capability will enable Landsat-7 to update a complete global view of Earth's land surfaces seasonally, or approximately four times per year.

NASA also is developing an advanced land imager instrument and related small spacecraft technology that will enable future follow-on measurements to be made by a sensor that is one-fourth the mass of the enhanced thermatic mapper and uses only 20 percent of the electrical power, while reducing the instrument's cost by 75 percent.

Landsat-7 was authorized by the Land Remote Sensing Policy Act of 1992, which established a joint NASA-U.S. Air Force program. This was superseded by a second Presidential Directive in 1994, that established a joint program between NASA, the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS).

Landsat-7 is part of NASA's Earth Science enterprise, a long-term research program designed to study Earth's land, oceans, atmosphere, ice and life as a total integrated system. Goddard Space Flight Center manages the development of Landsat for NASA's Office of Earth Science in Washington, DC.


Back to ASTRONET's home page
Terug naar ASTRONET's home page