Cohesive Methodology in Construction of Enclosure for 3.6m Devasthal Optical Telescope

Abstract

Building telescope enclosures is vital for setting up any optical observatory. An enclosure was constructed in remote hilly terrain to provide shelter to India’s largest 3.6 m Devasthal Optical Telescope (DOT). Primarily, the enclosure was built to protect the telescope from tough weather conditions and provide optimum space for performing various telescope related operational and maintenance activities. Other elements that were considered in the building enclosure were low thermal mass, sustainability, seismic and acoustic considerations. A steel building designed with mostly bolted connections, suitably selected materials, and mechanical systems for facilitating construction activities on site has been built for the telescope at the Devasthal site of ARIES. The enclosure construction was quite a challenging task with various project complexities. Multidisciplinary works of civil, mechanical and electrical systems in enclosure required efforts on various fronts in parallel to achieve the targets. Limitations of resources, manpower, and site conditions were managed to keep flexibility and economics in construction. Numerous challenges faced during the making of enclosures have been discussed in the paper. Insights into the construction of enclosures will provide a basic framework and learning opportunities for managing such typical construction projects in adverse weather conditions at mountainous sites.