"I was thinking about leaving, too," Jia says. "But exploring the universe was my childhood dream."

Over eight years, he helped to develop the Shenzhou-1 through Shenzhou-4 spacecrafts, Beidou navigation satellites, the China-Brazil Earth Resources Satellite, and the Ocean Satellite.

When his daughter was born in 2000, he named her Sihang, meaning focusing on aerospace.

The Chang'e lunar exploration program began in 2004. In July that year, Jia was asked to develop China's first lunar rover.

He had to simulate the environment of the moon's surface. What sort of traction would the rover have on the lunar soil? Would it slip? Would the wheels sink? These questions had to be answered on Earth.

Jia found that ash from a volcanic cluster in Northeast China's Jilin province was similar to the lunar soil samples brought back by the US Apollo missions.

Jia went to the provincial capital Changchun and traveled through snow-covered hills for several hours to Jingyu county. He was taken to a factory in the mountains, where the ash was used to make bricks.

Jia brought several truckloads of the ash back to Beijing.