By Stephen H. Wildstrom
TECH & YOU PODCAST
Too many products, too little time is the story of my working life. So it's not often that I play with a product for a few hours in the office, then take it home and spend another hour or so showing it off. But that's what happened with Google Earth (GOOG). I'm not quite sure yet what this satellite imaging program is good for or how it will make money, but it sure is fun.
A version of Earth had been available from Keyhole, a company Google bought last fall, but only to paying subscribers. Google has been incorporating the technology into its Google Maps service, and now all of the imagery is free. Unlike other Google services, this doesn't run in a Web browser but rather requires downloading an application -- currently only for Windows (MSFT) -- from Earth.google.com.
Using the program, which Google describes as "part flight simulator, part search tool," you can fly anywhere on the globe and zoom quickly from an outer-space view to a close-up that shows skylights, swimming pools, and individual cars on roads.
ZIPPING THROUGH SKY. Google Earth's brilliance lies in its mosaic of thousands of satellite and airplane images collected by Keyhole. For most urban areas of North America and some rural ones -- as well as metropolitan regions of Europe and select locations in the rest of the world -- you can make out objects as small as a few meters across.
Elsewhere, it feels like you're gazing down from a plane at 30,000 feet. The photos are also of varying ages, sometimes four years old or more, and were taken in different seasons. This can create jarring effects, such as seeing leafless trees burst into full foliage when you cross a seam in the image as you swoop around a neighborhood.
Running Google Earth on a PC with a decent graphics system and a speedy broadband connection, you really do experience the sensation of flight. A mouse with a scroll wheel helps. Turning the wheel zooms you in and out. Holding the wheel down and moving the mouse changes your perspective from a straight look down to a nearly horizontal view.
GLOBAL PERSPECTIVES. The service offers more than pretty pictures. You can superimpose map data showing streets, highways, demographics, or political boundaries, and turn these on and off with the click of the mouse.
Google Earth is also integrated with Google Local Search. So if you search for a business or attraction in some city, you'll get a marker on your satellite image, just like on a map. Click again, and the establishment's Web page opens below the image.
Keyhole built an online community around its images, and Google has maintained it. That means anyone can access a variety of map markers that volunteers have created and turn them on and off at will. One set identifies hundreds of Web-accessible traffic and surveillance cameras in the U.S. -- click on the camera's icon, and you can see what it sees.
PAID VERSIONS, TOO. Another set marks UNESCO historical landmarks around the world. You can create your own set of markers and post them or e-mail them to others.
One somewhat odd feature lets you replace the flattened, overview images of buildings in major U.S. cities with white shapes that represent the outline of the structures as seen from the street, but with no detail. This lets you create a three-dimensional, albeit very artificial, view of a city center and its skyline. But the addition of ground-based images, likely in the future, will create true 3-D pictures.
Google offers two paid, premium versions of Earth. The Plus edition ($20 a year) adds high-resolution printing and the ability to overlay data collected by global-positioning-system receivers. Pro ($400 a year) adds the ability to integrate data from commercial geographic-information systems.
But the free product is more than enough for most people. If you have the horsepower, download it and take an advance tour of this summer's vacation trip or check out your childhood neighborhood. You'll likely find it addictive. Wildstrom is Technology & You columnist for BusinessWeek. You can contact him at email@example.com