05-24-2015, 03:40 PM
Those windows are part of the dome ventilation system. UKIRT, the CFHT and Gemini all have similar systems. They're designed to keep the air temperature inside the dome the same as the outside air temperature at night. If the air inside the dome is warmer than outside then you end up with a column of warm air rising above the dome which causes local turbulence and degrades the delivered image quality; a problem typically seen during the first few hours of the night as temperatures drop rapidly.
The system at UKIRT gives an extra two or three hours of optimal image quality every night compared to nights it's not in use, so it's a very important part of the observatory's operations.
Edited for a typo.
The system at UKIRT gives an extra two or three hours of optimal image quality every night compared to nights it's not in use, so it's a very important part of the observatory's operations.
Edited for a typo.