Maps from Google Earth, a desktop application, can now be viewed online through a new browser plug-in.

In addition, Web site owners can now embed Google Earth 3-D views into Web pages.

"Driven by an extensive JavaScript API, you can control the camera; create lines, markers, and polygons; import 3-D models from the Web and overlay them anywhere on the planet," said Google engineer Paul Rademacher in a blog post. "In fact, you can even overlay your content over different planets, stars, and galaxies by toggling Sky mode, letting you build 3-D Google Sky mashups. You can also enable 3-D buildings with a single line of JavaScript, attach JavaScript callbacks to mouse events, fetch KML data from the Web, and more." KML is a file format for displaying geographic data in a browser.

Rademacher says Google's goal is to open up the core of Google Earth to developers so they can create the next great 3-D geo application.

Web sites using the Google Maps API can now enable those maps to be viewed through Google Earth's 3-D view. All that's required is a single line of JavaScript code. Further details are provided in the Google Earth plug-in documentation.

The plug-in works only with Windows XP or Vista at the moment. "Support for other operating systems is planned in future releases," Google promises.

The following browsers are supported: IE 6.0+ , IE 7.0+, Firefox 2, Netscape 7.1+, Mozilla 1.4+, and Flock 1.0+. Google says that Firefox 3.0 support is coming. Support for Safari will likely arrive when a Mac-friendly version of the plug-in is released.