UK team successfully complete latest step in bringing world's largest telescope to life

20 December 2018

UK engineers and scientists leading the project to build HARMONI, one of the first-light instruments for the Extremely Large Telescope (ELT), are celebrating after it successfully completed the Preliminary Design Review process (PDR). By completing this vital step, the instrument can progress to the detailed design phase, aiming to be ready for cutting-edge observations of astronomical objects when the ELT sees first light in the mid 2020’s.

Perched over 3,000 metres above sea level on top of Cerro Armazones in the Atacama Desert of northern Chile, the ELT will be the biggest optical telescope ever built and have a giant main mirror 39 metres in diameter. It is one of the biggest global science collaborations in history and includes an £88 million investment by the UK Government.

HARMONI — the High Angular Resolution Monolithic Optical and Near-infrared Integral field spectrograph — has been designed by a team led jointly by the University of Oxford and STFC’s UK Astronomy Technology Centre. HARMONI will provide the European Southern Observatory (ESO)’s telescope with a sensitivity that is many hundreds of times better than any current telescope of its kind. The Review assessed the design of the instrument's optics, mechanics, software, and electronics, as well as its operational concepts.

Speaking about this latest milestone astrophysicist Professor Niranjan Thatte who leads the University of Oxford team said
“HARMONI is a “work-horse” instrument and the spectrograph, equipped with an integral field capability and observes an astronomical target in 4000 different colours (wavelengths) simultaneously. Completing this review takes us all a big step closer to carrying out observations of a wide variety of astronomical objects, ranging from planets around nearby stars, to the very first galaxies, and the very first stars ever formed.”

As well as passing this major milestone, HARMONI is also set to gain a powerful new adaptive optics system. The ESO Council recently gave the green light to continue developing the Laser Tomographic Adaptive Optics (LTAO) system for HARMONI. The LTAO was originally deferred to a later phase of the telescope project. However, given its importance to HARMONI and the ELT’s science goals, and with the availability of additional funds from ESO and the HARMONI Consortium, ESO has been authorised to continue with this module. The LTAO system will make use of the ELT’s laser guide stars to allow HARMONI to acquire ultra-sharp images of astronomical objects anywhere in the sky.

Project Manager for HARMONI, UK ATC’s Ian Bryson said
“The UK ATC team are providing overall Project Management, Systems Engineering leadership of the Integral Field Spectrograph (IFS) and Control System and multi-disciplinary Engineering design for several HARMONI sub-systems. The huge contribution of ingenuity, expertise and enthusiasm from all colleagues in the consortium has been the key element in taking HARMONI successfully to this major milestone. Confirming the LTAO capability for ELT+HARMONI will deliver performance head and shoulders above any other facility built to date. The full ELT Facility will herald a great leap forward in our understanding of the cosmos.”

HARMONI is an integral field spectrograph, and will simultaneously acquire spectra at 30 000 adjacent points on the sky to map an astronomical object over a wide range of wavelengths. It is one of the first in a new class of massive astronomical instruments — HARMONI will stand an impressive 8 metres tall, measure 10 metres long by 6 metres wide, and weigh in at a mighty 40 tonnes.

Professor Simon Morris, Head of Durham University’s Physics Department is also one of the UK’s ELT project leaders and said
“The incredible scale of the ELT, and the range of its instrumentation, means it can address a huge list of scientific questions, but to bring the project to a successful completion takes time. It is over ten years since the UK team started working on the initial proposals for HARMONI. Completing the Preliminary Design Review process successfully, along with confirming the funding for the required adaptive optics system, are very exciting milestones on the path to first light.”

The UK ELT Project Office is funded by the Science and Technology Facilities Council (STFC). It co-ordinates activities across the UK’s principal partners for research and development for the project including Durham University, University of Cambridge, University of Oxford, and STFC’s UK Astronomy Technology Centre and RAL Space facility, in close collaboration with the European Southern Observatory (ESO).

The HARMONI Consortium consists of six main partners, and a number of associate institutes. The main partners are the University of Oxford (UK), the Science and Technology Facilities Council’s UK Astronomy Technology Centre (UK), the Centre de Recherche Astrophysique de Lyon (France), the Laboratoire d'Astrophysique de Marseille (France), the Instituto de Astrofísica de Canarias (Spain), the Centro de Astrobiologia (CSIC - INTA) (Spain), and ESO. Durham University (UK), currently an associate, will soon become a full partner. Other associate institutions are: the Office National d'Etudes et de Recherches Aérospatiales (France); L'Institut de Recherche en Astrophysique et Planétologie (France); STFC’s RAL Space (UK) and L’Institut de Planétologie et d’Astrophysique de Grenoble (IPAG).

The design of HARMONI makes it easy to calibrate and operate, providing the ELT with "point-and-stare" spectroscopic capabilities ideally suited to fully exploit the scientific potential of the telescope in its early years. HARMONI is part of the first-light instrument suite, which also covers imaging capabilities with MICADO/MAORY, and mid-infrared capabilities with METIS.

STFC’s UK ATC has led the UK ELT Programme for over a decade, coordinating UK roles in instrument development for this facility. The UK Programme includes leadership of the HARMONI instrument, the first-light spectrograph for the ELT, and has a smaller role in the METIS, the mid-infrared imager/spectrograph. The UK is also a key partner in plans for the next instruments, HIRES and MOSAIC. The UK ATC has technical roles in each of these instruments.

Astronomers and engineers at Durham University’s Centre for Advanced Instrumentation (CfAI) are involved in a number of the proposed instruments for the ELT including:

  • Developing adaptive optics technology for HARMONI to remove atmospheric blurring, allowing astronomers to see distant objects more clearly;
  • Designing the overall mechanical structure and providing adaptive optics for the multi-object spectrograph MOSAIC, which will allow astronomers to observe different areas of the sky at the same time.

Some of the components will be built and tested at the CfAI’s facility at the NETPark science and technology park in County Durham, UK.


Last updated: 20 December 2018

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