February 20, 2006
The Landsat Program: 22 Years and Still Counting
Please note that contributed articles, blog entries, and comments posted on GIScafe.com are the views and opinion of the author and do not necessarily represent the views and opinions of the management and staff of Internet Business Systems and its subsidiary web-sites.
Message from the Editor -
development of Landsat 8 and energy research. Read about it in this week's Industry News.
GISWeekly welcomes letters and feedback from readers, so let us know what you think. Send your comments to me
Susan Smith, Managing Editor
The Landsat Program: 22 Years and Still Counting
By Susan Smith
The recent repair of Landsat 5, designed to last 3-5 years, was met with a great sigh of relief by the geospatial community. Launched in 1984, Landsat 5 has had some issues over the years but has been able to weather those problems for an incredible 22 years.
Landsat 5 was part of a series of seven satellites launched in 1972 by the U.S. government. 1-4 have basically died, according to Ron Beck, program information specialist in the USGS Satellite program. Landsat 6 never made orbit.
In November, 2005, 5 developed the most recent problem. There is a solar array panel to collect sunlight on the solar batteries to provide the electricity to run the sensors on the satellite. “That solar array has to be adjusted fairly regularly on each orbit to get the right angle for solar collection,” explained Beck. “That mechanical device to adjust on the solar array quit functioning in November, so we were not getting the full angle on the sun and consequently, we were not getting enough electric power to operate the sensor effectively.”
USGS and NASA engineers adjusted it. The solar array was designed to operate at three different speeds: slow, medium and high speed. “High speed was designed in case there was a particular issue in which we had to adjust the solar panel quickly,” said Beck. Having operated for over twenty years at speed #1, “we cranked it up to speed #2 and it works. Now how long it will work, we don't know, we hope it will work for another four or five years. there's no way to predict.”
“Landsat 7 is our most recent satellite and the two [satellites] are in compatible orbits. It takes each satellite about sixteen days to cover the full planet. They're in orbits that are in effect eight days apart, so if one of them flies over your area today, eight days from now, the other one will fly over.”
where there are gaps in the data. It's as though you're looking through a Venetian blind, almost. We've found computer programs to compensate for that problem, and although we can't fix it, we are still getting 80% data.”
Beck said that during Katrina, the government was able to gather some very useful data from Landsat 5 and 7. Strangely enough, the center of each picture [from Landsat 7] was fine, and New Orleans just happened to be in the center of the images, so they got good coverage.
The science community has relied on Landsat 5 for a long time, and the loss of its operation as well as problems with 7 created a data gap.
The good news is that the current administration in the White House has recognized that Landsat has been dubbed an “experimental” program since its inception, and now has stated that it can now be called “operational.”
With this statement comes the okay to start working on a successor to Landsat 7. On February 6, the USGS sent out a
press release announcing the 2007 budget request for the USGS is $944.8 million. The budget will “add $40.1 million in new program and fixed cost funding which is offset by redirecting $49.9 million from lower priority activities and eliminating $10.0 million in earmarked funding.”
The natural disasters of the past year have heightened the USGS's needs for earth observation, energy research, and multi-disciplinary natural hazards research, monitoring and warning systems. $5.7 million will be set aside for a multi-hazards pilot initiative, which will include the development of Landsat 8 and energy research.
The 2007 budget seeks an increase of $16.0 million to fund Landsat 8 development, and an increase of $2.0 million to “meet mandates of the Energy Policy Act of 2005, including a national assessment of oil shale resources, preservation of geologic and geophysical data, and gas hydrate research to expand work on the North Slope of Alaska and on the outer continental shelf, ” according to the press release.
It takes 3-5 years to build a new satellite, according to Beck. In the meantime, people need a continuous record of data, so it's important to maintain satellite data without interruption. At this stage, in the event that 5 and 7 would both go down, Beck said that “We archive and distribute some older commercial data form a French satellite system, but mostly we work in partnership with the commercial sector so that your readers would go directly to them, not to us.”
Top News of the Week
CarteGraph announced the release of its new ArcGIS-embedded products, GEODATAconnect and GISdirector. The new products were developed with the assistance of ESRI technical staff and local government clients. A number of current CarteGraph clients have installed and implemented the software and are currently using it for their day-to-day operations.
CarteGraph GEODATAconnect and GISdirector will bring the power of CarteGraph's flexTECHNOLOGY-fully customizable software-to the geodatabase and make TRUE Public Works Management embedded in ArcGIS a reality. GIS users and public works professionals will be able to create and edit data either via CarteGraph software or through ESRI ArcGIS Desktop or ArcObjects tools.
Safe Software Inc. announced the release of SpatialDirect 2006, the most recent version of the company's spatial data distribution and transformation technology for the web. Based on innovative technology in Safe Software's Feature Manipulation Engine (FME), SpatialDirect allows organizations to easily and efficiently deliver map data via the web, in many different formats and coordinate systems.
MetaCarta(R), Inc., a provider of geographic intelligence solutions, announced that its technology has been chosen for inclusion in Raytheon's Direct-access User Knowledge Environment (DUKE) Information Management System, a messaging system used by the Defense Intelligence Agency (DIA). The integration of MetaCarta's GeoTagger technology by Raytheon allows the DUKE system to exploit unstructured text messages, producing valuable geospatial content that is incorporated together with other data for display and interpretation by the intelligence analyst.
GlobeXplorer has announced the latest functionality addition to their ImageAtlas aerial/satellite/map viewer: the ability to instantly pick, compare, and purchase images from multiple dates.
Users simply zoom to their area of interest and then click on a pull-down menu to select from all of the versions of imagery GlobeXplorer carries at that location and zoom level. Multi-date picking gives ImageAtlas users full access to GlobeXplorer's industry-leading catalog of imagery spanning back 15 years, and in some areas, much further.
You can find the full GISCafe event calendar here.
To read more news, click here.
-- Susan Smith, GISCafe.com Managing Editor.
Be the first to review this article