WorldWide Telescope, a free program that turns the cosmos into a visual dictionary, has added a plugin that allows virtual astronomers to train their amplified eye on Earth and to look back in time.

The original Telescope, from Microsoft Research and powered by Silverlight, can be employed in a browser and downloaded to a user's device. Scroll about the night's sky and select one of millions of celestial objects, then click on it and you will access astronomical information such as a galaxy's wave length, as well as interpretive data, like papers on the object from peer-reviewed journals.

Technology Review quoted Harvard astronomy professor Alyssa Goodman, a longtime user of the software, and founder of the WorldWide Telescope Ambassadors program, as describing the Telescope this way: "Objects in the sky become the hyperlinks themselves."

The new plugin, or "add-in" as Microsoft calls it, is attached to the company's Excel spreadsheet program. As the company puts it:

"The add-in enables a range of data sets to be visualized in WorldWide Telescope, including event data based on latitude and longitude (or RA and Dec if it is space based data), and geometry data specified in Well Known Text (WKT). As changes are made to the Excel data, the add-in enables the visualization to change dynamically to match the new data."

The UI includes a visualization selection to map data headings to their WorldWide Telescope labels, a layer manager and capture, go to and manage viewpoints buttons.

Mapping data to the Telescope database can produce dynamic graphics tracing, like say, the spread of the bubonic plague across Europe, a visualization of earthquake data over the last decade, or of possible historical routes for the dissemination of a language.