4MOST – a telescope facility that is set to become one of the world’s most powerful tools for large-scale astronomical surveys – has obtained its first light, a key milestone that marks the beginning of its scientific operations. The University of Bath is one of only three UK universities engaged as institution partners in the 4MOST project.
4MOST (4-metre Multi-Object Spectroscopic Telescope) – which was developed by a consortium of leading international institutions and is installed on the 4-metre VISTA telescope at the European Southern Observatory’s (ESO) Paranal Observatory in Chile – is the largest multi-object spectroscopic survey facility in the southern hemisphere. It is unique in its ability to observe a very large field of view and to investigate a large number of very different objects and science cases simultaneously in great detail.
The telescope does not simply take images of the sky – it records spectra, capturing the light of each object in every individual colour. With this capability, it can unravel the light of 2,400 celestial objects simultaneously into 18,000 colour components, allowing astronomers to study their detailed chemical composition and properties.
Once fully operational, 4MOST will investigate the formation and evolutionary processes of stars and gas in the Milky Way and other galaxies. It will also study black holes, other exotic objects and the Universe as a whole.
By analysing the detailed rainbow-like colours of thousands of objects every 10-20 minutes, 4MOST will build a catalogue of temperatures, chemical compositions, velocities and many more physical parameters of tens of millions of objects spread across the entire Southern sky.
Researchers from Bath’s Astrophysics Group in the Department of Physics are contributing to both galactic and extragalactic surveys, exploring phenomena ranging from nearby stars in our galaxy to remote galaxies, supermassive black holes, and explosive cosmic transients.
Dr Patricia Schady, an observational astrophysicist at the University of Bath, is co-leading a key working group responsible for the Survey Programme Validation (SPV). Scheduled to begin early next year, the SPV marks a major milestone for 4MOST as it will analyse the first scientific observations using the new instrument.
Dr Schady said: “This will be the first opportunity for members of the 4MOST consortium to test the telescope’s performance and confirm that the scientific goals of each survey can be achieved within the five-year observing programme. It’s going to be incredibly exciting to be at the observatory and to be among the first to see and analyse spectra of thousands of astronomical sources observed simultaneously.”
4MOST principal investigator Roelof de Jong, Milky Way section head at the Leibniz-Institut für Astrophysik Potsdam (AIP), said: “It is incredible to see the first spectra from our new instrument. The data look fantastic from the start. This bodes well for all the different science projects we want to execute.
“That we can catch the light that has travelled sometimes for billions of light years into a glass fibre the size of a hair is mindboggling – an incredible feat only made possible by an incredible development team.”
Development of the 4MOST facility started in 2010 and the facility has been designed to operate for at least the next 15 years.