Rendering of the PFS-A on its supporting platform

This artistic rendering shows the first ELT prefocal station (PFS-A) on top of its supporting platform in this image. Using guide star measurements the ELT prefocal stations will continuously check the alignment of every mirror on the ELT and will maintain the optimal shape of the giant M1 mirror by correcting the position of the 798 individual segments with nanometer precision. Apart from correcting the alignment from the telescope’s position changes and constant atmospheric changes the station’s flat mirror will also direct the light from the telescope to the many scientific instruments and devices that will lie on either side of the ELT’s main structure.