It has taken over a decade to build MOONS (the Multi-Object Optical and Near-infrared Spectrograph), led by the UK Astronomy Technology Centre (UK ATC) in Edinburgh. It will capture optical to near-infrared spectra from 1,000 celestial objects simultaneously. Standing at 4.5 metres tall and weighing 10 tonnes it is the largest astronomy instrument ever constructed in the UK.
Meticulous testing, including vibration, software and hardware checks, must be formally carried before the instrument is determined as ready to send to the European Southern Observatory's (ESO) Paranal site in Chile where it will be integrated with the Very Large Telescope (VLT). This rigorous assessment process ensures MOONS meets all operational standards and can achieve its scientific objectives.
After replacing several motor systems MOONS underwent its final cool down to -130C and full system test in October. Now MOONS is ready to be packed and shipped in early December. This process will take two months, including a 7,000-mile journey by boat to Chile. Following its arrival, it will take approximately six months to pair with the VLT, with first data expected by the summer/autumn of 2026.
Oscar Gonzalez, Head of Project Science at UK ATC and Deputy Principal Investigator of MOONS, said: “It's incredibly exciting that MOONS has passed these final tests, and we move one step closer to the instrument seeing first light in Chile. The congratulations go to the whole team who have worked so hard to bring us to this point."
Suzanne Ramsay, ESO Deputy Instrumentation Programme Manager, said: “The ESO team has been really impressed by both the instrument and the dedication of the MOONS team during this important and long test phase. We look forward to the installation on Cerro Paranal in keen anticipation of the scientific discoveries to come."
MOONS is a collaborative effort involving an international consortium from six countries, with the UK ATC leading the initiative.
Its unique capabilities will be used to survey millions of celestial objects. Combined with the power of the VLT, MOONS will provide the tools necessary to study galaxy formation and evolution over most of the history of the Universe with unprecedented detail.
