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Keith Raybould: For the past ten years, Keith Raybould has been chief operating officer at the Monterey Bay Aquarium Research Institute in Monterey Bay, California, developing technologies and test beds for ocean observing systems that, in his words,

budget. The strict implementation of an error budget was a discipline brought to the project by system engineers experienced in managing complex technical projects. “The error budget for Gemini was very,

are: “looking into the ocean depths

very rigid,” recalled Rick McGonegal. “The error budget became a

instead of looking upward to the skies.”

discipline, trying to prove that you were going to match your error

The ocean observing technologies are being developed to prove the feasibility for an upcoming NSF MRE-FC (major

budget, but of course if you’ve been though these kind of engineering exercises before nobody ever meets their error budget! But, the fact that you have one and everybody’s working on it means that in the end somehow it all comes together.”

research equipment and facilities construction), project called the Ocean Observing Initiative (OOI). Earlier in his career he worked for the U.K. Large

Of course, Gemini’s image quality standards were eventually met, but as expressed by Rick McGonegal: “As far as I can tell, the imaging and all of that kind of stuff probably outperformed the expectations of people outside of the project,” he said. “But, I think inside of the

University and managed the technical

project we were always pretty confident that we could do this.”

to a recommendation that the U.K. partner with the U.S. and Canada on

According to Jim Oschmann, one of the challenges during the commissioning of the optics (when the mirror was being used in open loop mode, without real-time image quality (wavefront)

the Gemini project. He joined Gemini in

feedback) was meeting project expectations for image quality. “The

1991 to help lead the engineering group

basic telescope image quality at 2.2 microns was very difficult, not

during construction and stayed until construction was complete in 1999.

Gemini North telescope showing the ventilation gates fully opened for a night of observations. The support building for the Gemini North enclosure is more compact than at Gemini South due to budgetary constraints in the early development of the project.

not everyone beyond Gemini’s offices shared the team’s confidence,

Telescope Project team based at Oxford

developments for a proposal that led

Figure 3.

thermal emissivity of less than 4%) was at the core of every error

only to meet but to prove we made it,” he pointed out. “It was almost impossible to prove in the early years, and I think only over a long period of time with a lot of statistics could you eventually tweak the telescope and have enough data to ensure that indeed it is there, because when you’re measuring the total system performance you have the atmosphere [to contend with]. You’re kinda chasing your tail a bit in the early months.”

June2009

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Issue 38 - June 2009  

GeminiFocus