Yarchen Monastery in Baiyu county, Sichuan province under the Milky Way, on Sept 9, 2015.[DAI JIANFENG/CHINA DAILY]

On his birthday in May, Dai decided to quit his job and became a freelance photographer. "A sense of mission and responsibility has grown in me as I have shot the stars," he said. "I have recorded so many beautiful scenes of the night sky that no one has seen and I should share them with other people."

Wang Xiaohua, general secretary of the night sky working committee at the China Biodiversity Conservation and Green Development Foundation, said Dai is an outstanding photographer who also is keen on dark-sky preserves.

"Dai extends his love of starry nights to protection of dark skies, and he uses his own photos to call people's attention to them," said Wang, an activist for dark-sky protection in China, who works for the Chinese branch of the International Dark-Sky Association.

In July, when Wang was promoting dark-sky protection in Lhasa, the capital of Tibet, he and Dai met, hit it off and became friends. Wang told Dai that the association needed photos of starry nights in Tibet's Ngari prefecture, but could not pay him. Dai took them anyway, and in August they were presented at the 29th general assembly of the International Astronomical Union in Honolulu to promote China's first Dark-Sky Reserve in Ngari.

"The best dark-sky regions are all located in remote regions. Dai's photos give more people the chance to see the beautiful nights there, and to become aware of the importance of protecting them," Wang said.

Dai plans to shoot photos of the entire Himalaya range. "The south and north sides of the Himalayas, though different in geography, culture and religion, share the same sky," he said. "In space, we have no national differences. I want to communicate that to others through my photos."

Cheng Yingqi contributed to this story.

Contact the writers through tanyingzi@chinadaily.com.cn