By / par Michael Balogh, CATAC Chair
(Cassiopeia – Summer / été 2018)
In April, CATAC submitted recommendations on the three design choices for the Wide Field Optical Spectrograph (WFOS), the result of a five month period of information gathering and community consultation. As one of only two first light instruments, the success of WFOS is critically important to the success of TMT. Our recommendation was that, while all three designs are exciting and capable of delivering excellent science, the Xchange design provides the best match to the top-level specifications. Moreover, the flexibility of this design, relative to the survey-oriented fibre design, is preferred. The final report is available on our web page.
Following this report, the instrument underwent a cost and risk review. At this review it was decided that the slicer design would not be pursued any further. Both the Xchange and fibre designs were found to significantly exceed the cost cap, and the instrument team has been charged with looking at how the designs can be altered to reduce cost. Neither design has a significant technical advantage or disadvantage; both have risks that will require some work.
The design work is expected to be completed by early July, to allow the SAC to make a recommendation by their July 26 meeting. In addition, a sub-committee of the TMT SAC has been formed to re-visit the science specifications that were originally defined for WFOS over a decade ago. The recommendations made by the sub-committee will also be discussed by the full SAC at that next meeting. The other TMT communities are undergoing a consultation process similar to the one held in Canada, and this information will be considered as well. There is still time for your voice to be heard, and if you have comments or concerns about WFOS please contact any CATAC member.
Work is also underway to select the third instrument to be built for TMT. Eight white papers have been submitted to the SAC, and these are currently being reviewed by a SAC subcommittee that includes representation from all the partners.
At the CASCA meeting in Victoria, it was announced that the next TMT Science Forum will be held December 10-12 in Pasadena, California. This will be an important meeting, likely coming after the pending legal decisions in Hawai’i have been resolved. We hope that many Canadians will consider attending this meeting. It is likely that some funding will be made available to help those who need it; an announcement will be made in the coming months.
Funding and Construction Developments
Gary Sanders (Project Manager) and Christophe Dumas (Observatory Scientist) summarized the current state of the project very well in their presentations at the CASCA AGM. There is lots of design and construction activity underway as we await the outcome of the permitting processes on both Maunakea and the alternate site in the Canary Islands.
As announced earlier this year, the US National Science Foundation (NSF), NOAO, TMT International Observatory and GMT Organization are working together to develop Key Science Programs that will be presented to the Decadal Review process in the US. If this is ranked highly by the Decadal Review Panel, NSF has communicated that they will be prepared to support a significant share (at least 25%) of both GMT and TMT, to provide access for the US community. This is a welcome development that provides a path to full construction. There remain issues to be resolved, including the timing of any funding and the Canadian share in the project. CATAC will continue to keep you informed as the situation develops; in the meantime, feel free to contact any CATAC member if you have questions or concerns.