By Pat Hall (York University), MSE Management Group member
In December 2024, the CFHT Board of Directors made the following recommendation:
The Maunakea Spectroscopic Explorer remains an exciting and competitive concept. The Board appreciates the efforts of all those who have worked over the years to help define MSE’s technical and scientific readiness. MSE’s timeline is, however, strongly delayed, and at the present time the Observatory’s priority must be to ensure it continues to operate as a scientifically effective facility into the 2030s. For this reason, The Board does not approve any additional allocation of internal funds towards MSE activities, beyond those absolutely necessary to responsibly and safely bring current activities to a stop. The ultimate realization of MSE in some form currently remains the best plan for the long term future of CFHT. The Observatory, through consultation with the SAC and the User community may, however, explore alternatives to MSE that achieve compelling science that utilizes the unique site on Mauna Kea. The Board remains committed to achieving a scientifically productive future for CFHT beyond 2033, building on its long tradition of excellence and the outstanding work of the CFHT staff.
Following this recommendation, CFHT is winding down all MSE activities. The Board acknowledges that MSE in some form remains the current best plan for the CFHT site under the new astronomy lease at Maunakea. Support from the current and future CFHT community will be essential to determine what future capabilities the CFHT will have.
The near-term future of CFHT will include Community Surveys and (https://www.cfht.hawaii.edu/en/science/CommunitySurvey/) starting in 2027 at the earliest, possibilities for which will be discussed in detail at the next CFHT Users’ Meeting, May 26-28, in Quebec. (https://www.cfht.hawaii.edu/en/news/UM2025/). In response to the board’s recommendation on alternative instrumentation to MSE, interpreted as potential upgrades to CFHT prior to MSE’s implementation, the community was invited to present ideas and will discuss technological upgrades and alternatives at the upcoming CFHT Users Meeting’s instrumentation session.
The science case for wide-field 8-meter-class spectroscopy in general, and MSE in particular, remains compelling. Meanwhile, such spectroscopy is becoming a reality with PFS on Subaru, and work toward proposed dedicated facilities continues in the form of the ESO WST project (https://arxiv.org/abs/2405.12518) and the Spectroscopic Stage-5 Experiment (https://arxiv.org/abs/2503.07923). Partnership with those initiatives might be a way to involve CFHT in a future dedicated 8-meter class spectroscopic facility, if supported by the CFHT community.
Speaking personally as someone who has been an advocate for MSE since 2013, I know that the MSE scientific community worldwide made great efforts to secure funding to start this project sooner rather than later. I thank everyone in Canada and elsewhere who has worked on them to date.