1998


From: Stanford University

Giant SHRIMP Poised To Target Big Questions With Tiny Ion Beam

Picture the solar nebula, that hot cloud of gas and dust that collapsed to form our solar system. Where did the gas and dust molecules come from? And what was the sequence of events that transformed them from a swirling amorphous blob into the well-organized planets and atmospheres that we know today?

A brand new $2.5 million, 12-ton instrument called the SHRIMP arrived at Stanford this past April and is poised to answer these and other fundamental questions about the origins of our Earth and solar system. The SHRIMP is not a time machine, and it's not an overgrown crustacean. It's a Sensitive High Resolution Ion MicroProbe, arguably the most coveted instrument of its type in the world, equaled only by its twin at the Australian National University in Canberra, where both machines were designed and built.

This is the machine whose predecessors determined the ages of the oldest minerals on Earth in 1983, the oldest rocks on Earth (3.96 billion years) in 1989, and the oldest minerals in the solar system (4.56 billion years) in 1992.

The SHRIMP was purchased jointly by the Stanford School of Earth Sciences and the U.S. Geological Survey as a result of an agreement signed in 1989. Geological and environmental sciences Professor Gary Ernst, who was dean of earth sciences at the time, saw the SHRIMP as a remarkable opportunity to attract collaborative world-class geochemical research to Stanford and to enhance ties with the U.S. Geological Survey.

The SHRIMP is located in the basement of the Green Earth Sciences building and operates under the direction of Trevor Ireland, assistant professor in geological and environmental sciences, who came to Stanford from the Australian National University, and Joe Wooden of the U.S. Geological Survey. Brad Ito, also of the USGS, plays a critical role as full-time electronics technician. Mike McWilliams, associate professor of geophysics and geological and environmental sciences at Stanford, and Charlie Bacon of the USGS contribute to planning and coordinating the SHRIMP's busy research schedule.

Earth and planetary scientists already are lining up to get bits of their favorite rocks into the new SHRIMP, because this machine is not only shiny-new, super-fast and highly precise, it's also very easy to use. Give it a tiny grain of Earth, Mars, interstellar dust or other solid material, and the SHRIMP can divine the exact chemical constituents of the sample down to minuscule differences in atomic mass within 15 minutes. Four sample analyses per hour, 30-some analyses per day ­ that's enough information to satisfy a data junkie's habit indefinitely.

Rocks and minerals that Stanford scientists are preparing for the SHRIMP include bits of stardust from very old meteorites, minerals from far-traveled sedimentary basins in western Canada, and samples from deep crustal rocks coughed up by volcanoes in the Bering Strait region, near the border between Alaska and Russia.




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