Tibet has clear skies, ideal for astronomical studies, as it is 4,000 metres above sea level.

China will begin construction of the world's highest planetarium next year in Tibet, local officials said.The planetarium, which is China's first, will have the region's largest optical astronomical telescope, with a 1- meter-diameter lens, and become a major regional base for astronomical research and public science education, the Science and Technology Department of Tibet said.The telescope will be jointly developed by the planetarium and the National Astronomical Observatories, and be used for variable star, state-run Xinhua news agency quoted the Department as saying today."The instalment of the device will enable the planetarium to carry out professional astronomical research," said Wang Junjie, deputy head of the department."The planetarium, with the highest altitude in the world, will become a 'perfect window' for the public to get to know the stars and explore the universe, thanks to little air or light pollution in the region," Wang said.Planned to be completed in 2019, the planetarium will be built within the Tibet Museum of Natural Sciences in Tibet's provincial capital Lhasa, the department said.

Dubbed the "Roof of the World" on account of its position 4,000 meters above sea level, Tibet has superb clear skies, ideal for astronomical observation, it said.