As a Chinese spaceship rockets through the void toward a rendezvous with a new Chinese space lab, experts say a monumental step in the nation's long march in space exploration is about to occur.

On Monday morning, China's Shenzhou XI manned spacecraft was sent skyward atop a Long March 2F rocket that thundered away from the Jiuquan Satellite Launch Center in northwest China.

Shenzhou XI carries two male astronauts - 49-year-old Jing Haipeng and 37-year-old Chen Dong. After a two-day journey, they are to dock with and spend 30 days living and working in Tiangong II, a new Chinese space lab. It will be double the longest stay by Chinese astronauts in space.

Tiangong II was launched in mid-September to replace the Tiangong I space lab, after the latter was retired in March according to plan.

But even more important than the length of stay, the mission is a giant step toward China having a permanent space station. Not only that, it's a station that experts said is likely to be the world's only one after the International Space Station is retired around 2024.

The Shenzhou XI-Tiangong II mission is a sign of China's full readiness for a space station, according to Lieutenant General Zhang Yulin, deputy head of the Central Military Commission's Equipment Development Department and the manned space program.

Once the station is put into use, China will launch "several space missions" each year to transport astronauts, engineers and even tourists to it, Zhang said.

As Chinese across the nation raptly watched the new step into the heavens, President Xi Jinping sent a congratulation message from the Indian state Goa where he was attending a summit of the emerging-market countries over the weekend.

Premier Li Keqiang and other high-ranking officials watched the start of the space mission from the headquarters of China Manned Space Agency in Beijing.

Source: Xinhua News Agency