Several years ago, my husband stumbled onto a subscription service from a company called Keyhole Corp. The service provided detailed satellite views of locations around the world and let us "fly" to locations, explore, and zoom in—in some cases close enough to see the color and model of cars in a parking lot. We checked out our neighborhood and many other locations we wanted to "visit." Then, in 2004, Google purchased Keyhole. Along with many others, we wondered what would happen, especially given the growing interest in Web mapping applications and location visualization.
This spring, Google integrated the Keyhole satellite photos into its Web search mapping applications. When using Google Maps or Google Local, users can plot driving directions and pinpoint locations on detailed satellite maps. It's actually very nifty—you can switch between the map view with streets labeled to the satellite view to see the buildings and landscape. But, the bare-bones, Web-based implementation lacked many features that had been available in the sophisticated subscription service.
Google has just released an enhanced and upgraded software version of the Keyhole application and has definitely kicked things up a notch in search visualization. The free-to-download program, now named Google Earth (http://earth.google.com ), offers satellite imagery-based mapping that combines 3-D buildings and terrain with mapping capability and Google search. Google calls it "A 3D interface to the planet."
Google Earth uses broadband streaming technology and 3-D graphics, much like a video game. This is a seriously cool application. Users can tilt, rotate, and activate the 3-D terrain and buildings for different perspectives on a location. Integrated with Google Local search, it lets users pinpoint local information such as hotels, restaurants, schools, parks, and transportation.
The whole world is covered with medium resolution imagery and terrain data, letting users see the major geographic features and towns but not the details of individual buildings. Additional high-resolution imagery that reveals detail for individual buildings is available for most of the major cities in the U.S., Western Europe, Canada, and the U.K. Three-dimensional buildings are represented in 38 major U.S. cities. Detailed road maps are available for the U.S., Canada, the U.K., and Western Europe. And Google Local search is available for the U.S., Canada, and the U.K.
You can attach notes, called "placemarks," to the map. Searches and placemarks can be saved in a "Places" folder. Google Earth allows you to print, save, and even e-mail images as a JPG or a KML (a data exchange format for placemarks) to another Google Earth user.
For users interested in more advanced mapping capabilities, Google Earth Plus ($20/year) offers additional features including GPS compatibility, data import, and more sophisticated annotation capabilities. Google Earth Pro ($400/year), intended for commercial use, offers high-resolution printing and GIS data import capabilities.
As I was working on this article, the site posted this message: "We appreciate your interest in accessing 3D geospatial information, but due to the technical limitations of this beta launch, Google Earth has been forced to take a brief breather. Please check back with us soon." Looks like so many people raved about the features that users flooded the Google servers—e.g., Chris Sherman called it an awesome application in SearchDay. Bloggers and other media have been similarly impressed. As I finished the article, the download capability was back, this time with more explicit details about the requirements to run the software. It's not available yet for Apple Macintosh computers, only Windows PCs. Notebook PCs older than 2 years and desktop PCs older than 4 years may not be able to run it, due to requirements for the screen display, 3-D graphics video card, CPU speed, and system memory.
Meanwhile, Microsoft recently announced that its new MSN Virtual Earth service is to debut in the summer. MSN promises a new twist on the satellite images—a 45-degree angle view of buildings. In addition, the service, based on Microsoft's MapPoint technology, will let users add street map and local data overlays on the images. At the site (http://www.virtualearth.com ), which promises that the service is "coming soon," the company calls it "global access to local knowledge."
Here are some of the promised details:
- Ability to select specific search results and store them in the MSN Virtual Earth Scratchpad
- Ability to send an e-mail message to any e-mail account from the Scratchpad feature or to a blog on MSN Spaces
- Satellite map view (using Microsoft TerraServer-USA .NET Web Service)
- New map-satellite hybrid or combined map view in which street locations, street names, and points of interest are overlaid and displayed on top of the satellite images
- Oblique imagery supplied by Pictometry International Corp. under an exclusive license with Microsoft.
Others competing in the Web mapping space include Yahoo! Maps (no satellite views yet, though it does offer nifty map overlays with traffic reports and Wi-Fi hotspots) and A9.com. Earlier this year, Amazon's search subsidiary A9.com added 20 million street-level photos that are displayed alongside local business directory search results. It started with 10 major cities and has been adding others. Users can navigate a 360-degree view and see nearby businesses. So, users have increasing numbers of options for finding their way virtually—maps, driving directions (unfortunately, not always accurate), photos, and now 3-D satellite views.