26 May 2022

ING is pleased to announce that, on Wednesday 25 May 2022, the WEAVE prime focus unit was successfully mounted on the WHT. The prime focus unit hosts the six large lenses of the optical corrector, the instrument rotator, the fibre positioner with its two robots, and nearly 4000 optical fibres. After assembling the positioner to the corrector on Monday, and arranging cables and fibres on Tuesday, the entire assembly, weighing 7.7 tons, was lifted on Wednesday. Once attachment to the prime focus ring of the telescope was completed, the pre-tensioning elements were installed. Eight mechanical engineers and technicians from the ING staff completed the lift in close to 9 hours.

In the coming days, work continues running the fibre cables to the spectrograph, installing the control electronics cables, and completing the tensioning of the telescope vanes. The system will then be ready for continuing calibration and verification tasks on the positioner. WEAVE on-sky commissioning is planned for this summer, after which the observations of the science verification programme will be carried out in the fall.

[Image]

(A) WEAVE on the WHT. 

(B) Smiles at the end of the day: some of the mountain-top team responsible for installing WEAVE on the WHT on 25th May 2022. Credit: Javier Méndez.