1994 was a year of great activity. The instrumentation plan was defined, fabrication of the primary mirrors continued, site preparation began at both sites, and 40% of the total funds were committed in major contracts.

The Gemini Science Committee reassessed the science requirements for infrared chopping and developed optical and UV image quality requirements for the f/16 focus. The Gemini Instrumentation Plan was formulated and approved by the Board in May 1994, with three science working groups set up to oversee the plan.

The first Gemini Systems Review, in July 1994, examined the overall program technical status, with emphasis on the Gemini Operational Concept Definition and the software system intended to implement the operational concept. Queue- based observing concepts were incorporated into the software system design. The Project presented a paper to the GSC entitled "An Assessment of Optimal Observing Modes with Gemini", making a case for substantial use of queued observations.

Amendment to Gemini Agreement signed

An Amendment to the Gemini Agreement was signed by all six Parties between May and August 1994. The Amendment adds Chile, Argentina, and Brazil as partners in the Gemini Project, and modifies the Agreement to include the shares these countries have in the Project. The Amendment also takes note that the UK partner is now represented by PPARC, not SERC.

Status of the Optical Systems

The Corning Company was awarded by AURA the contract to manufacture the primary mirror blanks for the Gemini telescopes. Corning will fabricate the blanks from ultra-low-expansion (ULE^TM) glass and slump them to the thin meniscus mirror shape, generate the blanks and grind the central hole, and deliver the blanks to the polisher. The first blank is due by 1 October 1995; the second by 1 March 1997.

First Primary

The production of the 84 boules of ULE^TM glass for the first mirror blank was found to be better than specification. The boules were fused to form the first blank on 20 September 1994. The fused blank surpassed specification, with almost no bubbles found. Slumping of the blank took place in March 1995.

Second Primary

All 84 boules for the second blank have been produced, and most of them were stacked into hexes by the end of 1994. They will not be fused until December 1995, after the first blank has been shipped.

Status of Other Major Subsystems

Most of the design studies for the primary mirror cell assembly have been completed. The design of the mirror support system is progressing at the Royal Greenwich Observatory, while the cell structure and thermal management system are being designed by the Project staff and by outside engineering firms.

The Request for Proposal for the secondary mirror Tilt System was released in June 1994, with a contract awarded in March 1995. The Request for Proposal for fabrication and polishing of the secondary mirror was issued in October 1994, with a contract scheduled for May 1995.

All major Optics Group contracts are expected to be in place by late 1995.


Mauna Kea

Proposals received in response to the Request For Proposal (RFP) for the construction of the Support Facility and Enclosure Base were of unexpectedly high cost. The Board approved the recommendations of the Project for a more modest support facility and to break up the original RFP into smaller pieces. with the Project itself becoming the prime contractor.

The San Juan Construction Company was awarded the road work contract, and began work in September 1994, but was halted for the season by an early snowfall.

Cerro Pachón

By August 1994, 20,000 cubic meters of rock were removed from the summit of Cerro Pachón, to provide a flat surface at bedrock. Construction of the road to the summit has begun.

Official ground breaking ceremonies

A ground-breaking ceremony was held at the Mauna Kea site on 7 October 1994, and a foundation stone was laid in a ceremony at the Cerro Pachón site on 22 October 1994.


Major contracts pre-1994

A major contract was awarded in September 1992 to Corning, Inc., to fabricate one 8-meter primary mirror blank with an option (later exercised) to purchase a second blank. This contract was amended in early 1994 to add the generation and grinding of a central hole in the two 8-meter blanks (see below). Another amendment was approved in early 1995 for acid etching of the blanks.

A work package was placed in December 1993 with the Royal Observatories for the aluminum coating process development and for the design, procurement, and installation of the Coating Plant.

The contract with Optical Data Associates, placed in 1993 for an 18-month program to develop a protected silver coating for the primary mirror, is underway. Two coatings are being investigated. The first is a silicon-nitride-protected silver coating, and the second is a hafnia-protected silver coating.

Primary Mirror Assembly System work package to UK

In September 1994, a Work Package was assigned to the UK for the primary mirror. The work (and funds) will be divided about evenly between the Royal Observatories and the Project, with the Royal Observatories responsible for the mirror support system and the primary mirror controls, and the Project responsible for the primary mirror cell structure and the thermal control system.

Other major contracts in 1994

In March 1994, a contract was awarded by AURA to REOSC Optique, to polish the mirrors, add metrology mounts, and transport the mirrors to the sites. The first mirror is to be delivered to Mauna Kea by February 1997, and the second to Cerro Pachón by April 1998.

In April 1994, the contract with Corning, Inc. was modified to add the grinding of the central hole in each blank, generation of the blanks to net mirror shape, and delivery of the blanks.

In May 1994, a contract was awarded to Coast Steel Fabricators to design and construct an enclosure carousel and a platform lift at each site. Assembly and installation at Mauna Kea will begin on 28 January 1996, with all work complete by 1 December 1996.

At Cerro Pachón, the assembly and installation will begin 20 April 1996, with all work complete by 8 February 1998.

Contracts between $250,000 and $1,000,000 before 1994

Contracts between $250,000 and $1,000,000 in 1994

Planned Contracts in 1995

Preliminary and Critical Design Reviews (PDR, CDR)

The telescope design was completed and a CDR was held in March 1994. An RFP was issued in early March, but complications in negotiation delayed selection of the contractor. A contract was awarded in March 1995 to G.I.E. TELAS and Framatome S.A. The secondary mirror PDR was held May 1994, with an RFP issued in June.

The PDR for the Cassegrain Instrument Support was held in June 1994.

The System Review #1, to consider the overall program technical status, with emphasis on the Gemini Operational Concept Definition and the software system intended to implement the operational concept, was held in July 1994.

The Software Design technical PDR was held April 1994, with the CDR in August 1994. The review committee found that the Gemini Controls Group is planning and engineering a well-conceived software system.

The enclosure design review was held in October 1994. Coast Steel has started to produce the enclosure fabrication drawings.

The coating plant, protected silver coating, and primary mirror cleaning PDR was held in November 1994. Excimer laser cleaning of the Gemini primary mirrors was selected, following studies of contamination removal by the Project and by STI Optronics. The Acquisition & Guiding Work Package PDR was held November 1994.


The Project Office went on-line on the World Wide Web on 5 April 1994. The Gemini home page describes the project and its current status. The Uniform Resource Locator (URL) for the home page is http:/ /www.gemini.edu/.

Back to the Annual Report Table of Contents