June 4 (Bloomberg) -- Google Inc., owner of the most popular Internet search engine, will lease 42.2 acres of land at a NASA research park near its headquarters to build more offices.

The Mountain View, California-based company will initially pay $3.66 million a year for the land at the Ames Research Center, Google and the space agency said today in a statement. The 40-year lease could be extended to 90 years. Google expects to start construction in September 2013.

Google's workforce increased sixfold since 2004 to more than 19,000 as the company overtook Yahoo! Inc. as the most popular U.S. Web site. Today's announcement solidifies a 2005 agreement to build a campus of at least 1 million square feet on the site. The company plans to construct housing, dining and sports facilities.

NASA plans to use the proceeds for maintenance and improvements at Ames, which was started as an aircraft research center in 1939 at the U.S. Navy base on Moffett Field. NASA took over the base when it was closed by the Navy in 1993.

Google rose $4.92 to $572.22 at 4 p.m. New York time on the Nasdaq Stock Market. The shares have fallen 17 percent this year.

To contact the reporter on this story: Vivek Shankar in San Francisco at vshankar3@bloomberg.net

Last Updated: June 4, 2008 16:30 EDT