UK ELT Programme

The Extremely Large Telescope (ELT) is now under construction in the Atacama Desert in northern Chile by the European Southern Observatory (ESO). With a diameter of 39m and a greater collecting area than all current large telescopes combined, the sensitivity and spatial resolution of the ELT will dwarf those of existing facilities in the visible and infrared. With the first observations planned for 2024, the sheer sensitivity of the ELT is truly remarkable, with a collecting area over 18 times that of ESO's current largest telescopes. The telescope will also continuously correct the light from astronomical objects with a technique called adaptive optics, giving astronomers images with five times better resolution than possible today.

This vast step forward in both collecting area and image resolution from the ELT will be transformative for nearly every aspect of contemporary astronomy, from searches for molecules potentially linked to life in nearby exoplanets, out to detection of the most distant galaxies at the edge of the observable Universe. It will give us our first detailed views of individual stars in galaxies which are millions of light-years beyond the Milky Way, and help to settle arguments as to whether some of the fundamental constants of physics vary in space and time. It will have the capabilities to directly detect mature planets similar to those in our Solar System around nearby stars, while also probing the distribution of elusive dark matter in galaxies when the Universe was just 10% of its current age. This is just a small subset of the diverse and profound scientific breakthroughs we expect from the ELT, and UK astronomers and engineers are playing leading roles in the development of the cameras and spectrographs that will take the valuable observations in the mid 2020s and beyond.

Building on a decade of scientific and technical development, the UK ELT Programme coordinates the UK roles in ELT instrumentation. At the core of the programme is leadership of the design and construction of the HARMONI instrument, one of the two first-light instruments for the telescope, ensuring UK astronomers will be well prepared to reap the rewards from ELT observations as soon as possible and some of its first discoveries.

The programme also includes smaller roles in future instruments, so that UK astronomers can exploit as much as possible of the tremendous new discovery space of the ELT. The UK is building the high-resolution spectrograph for METIS, the third instrument for the ELT, now in construction (led by the Netherlands). UK groups also have key roles in design studies of the next instruments, HIRES (led by Italy) and MOSAIC (led by France), both of which will be essential to exploit the huge scientific opportunities of the observatory. Lastly, the programme is investing in research and development of new technologies that will influence the design of future ELT instruments, particularly the development of the PCS instrument for studies of exoplanets.

The UK ELT programme has two main (non-academic) routes to impact: industrial contract return from ESO, including the instrument projects, and public engagement (PE). Both of these are dealt with through dedicated work-packages in the proposal, with further details given in the Pathways to Impact document.

1) Industrial return: The total hardware budget for the telescope construction project at ESO is more than 800MEur and most of that will be procured from industry in the ESO member states. UK companies are eligible to bid for ESO contracts and a major part of the industry engagement programme is to find suitable UK companies to put forward to receive calls for tender. There is still over 100MEur worth of ELT contracts to be let and through past efforts of the programme, UK companies are well placed for a number of specialist supplies in imaging detectors and software. The end goal of the programme is to see contract return to the UK increase so that we maximise our share of the construction budget. Our activities in support of this goal include publicising tender opportunities through email campaigns from the STFC tender opportunities service, targeted meetings with groups of companies and contract-specific events.

2) PE: Astronomy is recognised as a hugely inspiring way to engage the public with the big questions of science, and events such as Stargazing Oxford and Doors Open at Royal Observatory Edinburgh regularly draw thousands of visitors. We will leverage the existing PE programmes of the consortium (including the ROE Visitor Centre, STFC Public Engagement & Communications and Oxford University) and exploit the news value of significant ELT milestones between now and first light. The first phase of the programme will aim to engage audiences with the technology involved in building the ELT and its systems and will concentrate on `awareness raising' with social media campaigns, coordinating with ESO on press releases and embedding the ELT into wider STFC PE activities (e.g. piggybacking on the JWST launch). Subsequent phases will begin to plan activities leading up to telescope first light, and secure additional funding for
resource development and building partnerships with teachers, science centres, and planetaria in preparation for leading a series of national events.