ELT-HARMONI on track to deliver sharpest images ever

19 December 2018

The HARMONI instrument for the Extremely Large Telescope has completed a major milestone today, having successfully passed its Preliminary Design Review. The spectrograph, equipped with an integral field capability, observes an astronomical target in 4000 different colours (wavelengths) simultaneously. The project is an international collaboration of several universities, institutes and national laboratories, located in the UK, France and Spain. The project is jointly led by the University of Oxford (Principal Investigator: Niranjan Thatte) and the UK Astronomy Technology Centre (Project Manager: Ian Bryson). Key roles at Oxford include Lead Systems Engineer (Fraser Clarke), Instrument Scientist (Matthias Tecza), Project Scientist (Miguel Pereira-Santaella) and Project Administrator (Vanessa Ferraro-Wood).

The Extremely Large Telescope, currently under construction in Northern Chile, will be the world’s largest optical / near-infrared telescope, with a primary mirror diameter of 39.1 metres. It is expected to start operation in the mid 2020s. HARMONI will be part of its “first light instrument suite”, providing the spectroscopic capability at visible and near-infrared wavelengths. HARMONI is a “work-horse” instrument, and will carry 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.

At their December 2018 meeting, the ESO Council approved the design and construction of the Laser Tomographic Adaptive Optics (LTAO) module for HARMONI. LTAO will allow HARMONI to correct for the turbulence of the Earth’s atmosphere, enabling HARMONI to take the sharpest images the telescope can deliver, over the whole sky, thanks to six artificial (laser) guide stars. The images will be over 5 times sharper than the best ground-based telescopes can achieve today, and even 10 times sharper than those made using the Hubble Space Telescope. The combination of exquisite detail (from LTAO correction), and extreme sensitivity (from the large light gathering power) will mean that the ELT will stand 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.