2025 has been a year of profound transformation for the CTAO. We began this journey in January with a historic milestone: officially becoming an ERIC. This marked the official start of the CTAO construction phase. A major step forward.
This year we have seen the growth of our staff and the capabilities of our organisation. Across our Central Organisation headquarters in Bologna, the Science Data Management Centre in Zeuthen, CTAO-North in La Palma, and CTAO-South in Chile, our expanding team increasingly has the expertise and passion needed to push the project further than ever. We’ve also grown as a global family, welcoming Switzerland and Croatia as members of the CTAO ERIC. And this growth will not stop.
Looking at our sites, their vista is physically changing. At CTAO-North, the LST Collaboration has worked tirelessly and the final three Large-Sized Telescopes are nearly complete with their inauguration planned for 2026. Meanwhile, the SST and MST Collaborations have also made remarkable progress with the first telescopes expected to be delivered to our southern site in 2026. This is all being done with the support and guidance of the Central Organisation’s Telescope and System Engineering groups.
On the construction front at CTAO-South, foundations and roads are now under construction with an expected finish date in June. This monumental endeavour was just celebrated in our CTAO-South Groundbreaking Ceremony: the final great milestone of 2025. Together with the support of the Computing and Science teams, we will be ready to operate the telescopes and generate first data in 2027, in both the north and southern sites.
This progress is possible because of the dedicated work of the Central Organisation staff across all fronts—including the essential, behind-the-scenes efforts of our Administration and Director’s Office staff, whose support has ensured a smooth transition to the ERIC.
We want to make sure that the CTAO will generate fabulous science but also promote curiosity inspiring everyone from school children and university students to citizens and scientific leaders. This year we held the second CTAO summer school and awarded the first Werner Hofmann Scientific Award to an outstanding early career researcher.
2025 was a year of new starts and building foundations; in 2026 we will build further.
On behalf of the CTAO, I would like to thank our teams and partners around the world for their continued support and the opportunity to continue this journey together.
I wish you all a very happy holiday season and a prosperous New Year!
Stuart McMuldroch
CTAO Director General