If certain employees of the U.S. Geological Survey are begging for used tennis balls, it must mean that something big is brewing. And it is.

But it's not a tennis tournament or a new earthquake recorder that measures how much the tennis balls will dance in the next earthquake. No, it's bigger than that. It's the world, and the way kids will see it on the skin of a tennis ball at this year's edition of the USGS Open House in Menlo Park, May 13 and 14.

At the past three USGS Open Houses, making tennis-ball globes was such a popular activity that the planners are bringing it back this year, but they need help. At least 3,000 used tennis balls must be collected by May 12 to ensure that every child who attends the Open House and wants to make a globe will be able to do so.

The used tennis balls may be dropped off at the USGS Earth Science Information Center on the first floor of Building 3 on the USGS campus at 345 Middlefield Road in Menlo Park, or in the lobby of the USGS library at the same location. Hours at both locations are 8 a.m. to 4 p.m., Monday through Friday. On the weekends there will be a tennis ball collection box on the portico of Building 3.

For more information on the USGS Open House, call 650-329-4309, or preview the event at http://openhouse.wr.usgs.gov.

As the nation's largest water, earth and biological science and civilian mapping agency, the USGS works in cooperation with more than 2000 organizations across the country to provide reliable, impartial, scientific information to resource managers, planners, and other customers. This information is gathered in every state by USGS scientists to minimize the loss of life and property from natural disasters, contribute to the sound conservation, economic and physical development of the nation's natural resources, and enhance the quality of life by monitoring water, biological, energy and mineral resources.

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