Steel frame of the enclosure was completed and its rotation test succeeded

Optical infrared telescopes such as TAO are installed in buildings with large openings in order to avoid the effects of rain and wind. Many buildings used to be spherical, called ‘telescope domes’, but now many buildings are cylindrical or similar in shape, called ‘telescope enclosure’ generally.
As a telescope changes its pointing direction from moment to moment to track stars, the enclosure is required to rotate its opening accordingly. In TAO’s case, the rotating part of the enclosure is 25 meters high and 25 meters in diameter, so it is not easy to rotate it with precision.

▲TAO’s enclosure being tested its rotation. Steel frame of the upper rotational part is assembled.

After the steel frame of the rotational part of the enclosure was completed, the rotational test was conducted in October, 2023. The test was successful and confirmed to rotate very smoothly. It indicated that the bogies for rotation were installed with precision and that the underside of the rotating part was sufficiently flat. Having passed the rotation test, the enclosure assembly can now proceed to the next stage, the installation of exterior wall panels.

▲Bogies for telescope rotation. The bogies are fixed on the lower structure, and the upper steel frame is placed on them.