HET Mirror and VIRUS Structure (back view)

HET

The mirror of the Hobby-Eberly Telescope is seen from behind, highlighting its teal blue support structure. At left, the square black unit is one of two "saddlebags" that ride along with the telescope as it turns. Each saddlebag will hold multiple spectrographs that together make up the VIRUS instrument. At right, the louvers that look like blinds are visible. These encircle the structure. When open, they allow cool air to flow through the dome, keeping the temperature inside as close as possible to the temperature outside. This helps to maintain the quality of astronomical observations. Credit: Ethan Tweedie Photography