FRAMINGHAM (07/31/2000) - A virtual sea of information exists out there. There are infrared satellite photographs that detail cities and farm fields, along with databases bulging with information on transportation, commerce, population, crime, food production and everything in between.
Yet much of the data stored around the globe can't easily be used with other information. The data incompatibilities may result from using different file formats or coordinate systems (the mathematical means of locating a particular spot on the globe). Also, some metadata, which is information that describes the data itself, is missing.
Today, only a few experts know how to merge the combined raw data and look at it in new and useful ways. But that could be changing.
The Digital Earth program is a global effort to find easy ways for anyone, anywhere, to quickly get information from servers worldwide and blend it with other data on a desktop, regardless of any inherent incompatibilities in the data sets.
The uses for such a technology abound, from allowing a computer maker to map spare-parts inventories in regional warehouses to giving officials the chance to map a hurricane and quickly plan for mass evacuations of populated areas via major highways.
Digital Earth could also allow businesses to analyze employment data, rail corridors, parcel maps, demographic data and commerce data - all at once - to help rough out a new site for a manufacturing facility, without costly and time-consuming legwork.
"This is like the '60s, when we wanted to go to the moon," says one potential user, Rajesh Dave, a systems administrator in the geographic information system (GIS) department for Pennsylvania's Lancaster County. "We're at that stage."
Group Effort
Digital Earth is being spearheaded in the U.S. by NASA. Joining the space agency are the U.S. Geological Survey and the Environmental Protection Agency, along with foreign nations and companies such as Autodesk Inc. in San Rafael, Calif., Microsoft Corp. and Sun Microsystems Inc., which are all participating in a worldwide project that began in 1998.
Using Digital Earth, it will one day be possible to put together complex combinations of data, using a browser-equipped computer and typing in a request, say information technology professionals.
With Digital Earth, a user could choose a data source, such as a road map, on his browser and then select a region to analyze. The user could then add other data to the selected region as easily as clicking on any other choice on a menu. The user would quickly have a map with multiple layers of data that provides much more detail and information than is readily available today.
On to the Next Level
Currently, to merge incompatible data sets for such a map, you'd have to do a lot of custom programming or use complicated and costly GIS software.
The Digital Earth project hopes to solve that problem not by changing the data but by standardizing how it's cataloged and retrieved, through an OpenGIS standard. The data will be stored as it is today, in private servers around the globe. The servers will be linked by high-speed networks to route the data to processing centers and on to users. Intelligent agents will seek out and provide the data, instantly sending it where it's needed.
In preparation, the IT experts working on the Digital Earth project developed a Web-mapping test bed to see whether their theories would work. The test bed ultimately functioned properly and established special standards, called the OpenGIS Web Map Server Interface Specifications, to ensure that the system can be expanded to work around the globe on a huge scale.
A second test-bed project is being conducted to advance the technology to the next level. "Nobody has to change their data sets or create new data sets," says Thomas Taylor, the program manager for Digital Earth efforts at NASA's Goddard Space Flight Center in Greenbelt, Md.
What's being created is an environment that will let data be brought together easily, not an entity that will act as a huge data repository. By letting data remain on individual servers, it can continually and more easily be updated.
The data could also include weather statistics, roads, waterways, voting information, census data, zoning districts and much more - almost any information that is "geospatial," meaning it can be referenced to a given spot at a given time.
The project is being driven by the public sector as well as the commercial market and will likely include some free data. But no one knows just when it will be ready for everyday use, Taylor says. "You'll know you're there when you're there," he says.
Jeff de La Beaujardiere, an associate research scientist at the University of Maryland who's working at Goddard, says the project reminds him of the development of the Internet since 1995, when Net use took off. "Digital Earth will do for geo-referenced information what the World Wide Web did for text and multimedia," he says.