Carnegie Mellon University Department of Chemistry

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Carnegie Mellon‘s Sigma-5 Retires After 30 Years of Service

Say goodbye to Sigma-5.

One of Carnegie Mellon’s oldest, and when operational, one of its most vaunted scientific tools, will take its place soon in the Computer History Museum at NASA’s Ames Research Center in Mountain View, California.

It will join a collection of more than 3,000 artifacts, 2,000 films, 5,000 photographs, and thousands of gigabytes of software that help tell the story of computer evolution.

The Sigma-5 worked from deep within Mellon Institute since 1971 when the National Institutes of Health awarded it to Carnegie Mellon’s NMR Facility for Biomedical Studies.

There it was used to interpret NMR (nuclear magnetic resonance) data gathered by the facility. NMR is a tool that enables chemists and biologists to look at the structure of compounds and make calculations based on that structure. Similar tools are used today for DNA and genomic research, as well as in the development of new drugs. The Sigma-5 was responsible for taking spectra, or a graph of data, and applying it to various calculations.

Because it was connected to what was the most powerful magnet for NMR studies in the world, the Sigma-5 at Carnegie Mellon was responsible for more than 50% of the spectra published in the reviewed scientific journals in the United States.

“During the 1970’s, the facility was astonishingly successful, providing spectra at 250, and later at 600 Mhz, to investigators in organic and biochemistry in many states in the United States as well as investigators from Europe and Africa,“ says Chemistry Professor Emeritus Aksel Bothner-By.

Scientific Data Systems, which was later purchased by Xerox, originally marketed the Sigma-5 in 1965. Even after its commercial retirement in the early 1970s when Xerox stopped manufacturing mainframe computer systems, the system remained in use at the NMR Center under the supervision of Bothner-By and Chemistry Professor Josef Dadok, until the two professors retired in 1992.

The entire system included five, seven-foot tall cabinets, a main control panel, a large printer and a monitor. The Sigma-5’s size and performance show how computing power has changed. The large machine only holds 16 kilobytes of random access memory and just three megabytes of data in its hard drive; less than an ordinary personal computer now has. It also cost a whopping $300,000 when new.

The Sigma-5 will be an important contribution to the Computer History Museum and is still operational. “This donation is very significant in that few, if any, examples of early mainframe hardware still exist, especially in the complete and operational condition of the Sigma-5,” says Lee Courtney, a volunteer at the museum.

Its main console can be expected to be on display in the Computer History Museum within a few weeks.

Article courtesy of Carnegie Mellon Public Relations.

June 2002