The HAWK-I instrument at the VLT
The HAWK-I instrument mounted on the telescope's Nasmyth (side) port. HAWK-I is attached on Yepun, Unit Telescope number 4 of ESO's Very Large Telescope and saw First Light on the night of 31 July 2007. As the telescope tracks the celestial object under study, the entire instrument (2.2 tonnes) must rotate with great precision about its optical axis to hold the image stationary while the exposure is taken.
Credit:ESO/S. Guisard (www.eso.org/~sguisard)