Scientists building giant 'microphone for light' in Chile to search for aliens

Scientists have signed an agreement to build a giant spectograph - like a microphone for light - to search for aliens.

European Southern Observatory (ESO) officials signed an agreement with an international consortium of institutions for the design and construction of ANDES, the ArmazoNes high Dispersion Echelle Spectrograph.

The ANDES instrument will be installed on ESO's Extremely Large Telescope (ELT) in Chile.

It will be used to search for signs of life in exoplanets and look for the very first stars, as well as to test variations of the fundamental constants of physics and measure the acceleration of the Universe's expansion.

Formerly known as HIRES, ANDES is a powerful spectrograph: an instrument which splits light into its component wavelengths and records its findings so astronomers can determine important properties of astronomical objects, such as their chemical compositions. Picking up light so it can be analysed, rather like a microphone can do for sound.

The instrument will have a record-high wavelength precision in the visible and near-infrared regions of light and, when working in combination with the powerful mirror system of the ELT, it will pave the way for research spanning multiple areas of astronomy.

ESO's ELT is currently under construction in the Atacama Desert of Northern Chile. When operations start later this decade, the ELT will be the world's biggest eye on the sky, marking a new age in ground-based astronomy.