China is well on track to launching its own space station by 2020, according to a top rocket expert.

Long Lehao, a renowned academic and a leading designer of Long March 3A, the launch vehicle for the country's first lunar probe Chang'e I, described China's planned space station as "a small-scale 20-ton space workshop".

Long Lehao

It is the first time a timetable has been made public for the building of the first space station, the third and final step of the country's current manned space program, Long told China Daily.

Former president Jiang Zemin announced the three-stage manned space flight plan in 1992.

Marking the first stage were two manned space missions during the last four years, including the first by Shenzhou V in 2003.

The second stage, planned for Shenzhou VII in 2008 with several astronauts, will test spacewalking and other out-of-capsule space missions.

After that, China will be a substantial step closer to establishing its own space station, Long said.

It is expected to be the second operational one in the world after the International Space Station and the only one run by a single country, after Russia's Mir space station was decommissioned in 2001.

The 400-ton International Space Station is a joint project of 16 nations: the United States, Russia, Japan, Canada, Brazil and 11 countries from the European Space Agency, and orbits some 360 km above Earth.

China has expressed interest in becoming the 17th nation to join the project.

Long, one of the first researchers to push for heavier rockets 20 years ago, said he was optimistic about the space station plan because China had made significant progress developing a new family of rocket launchers.

He revealed that key technology breakthroughs - including the yet-to-be-built powerful Long March 5 carrier rockets - had put the project closer to production stage.

"Technologies for two key engines powered by liquid hydrogen and liquid oxygen along with regular energy were found to be more workable and reliable," Long said.

Each of the engines, one with a thrust power of 120 tons, and the other with 50 tons, have already undergone significant ignition testing, he said.

The carrier's increased diameter from 3.35 meters to 5 meters would allow it to carry heavier loads including space stations or heavyweight satellites, which the current Long March 3A rockets cannot handle.

The new-generation Long March 5 rocket is likely to undergo launch trials by 2013 and is expected to be the fourth most powerful rocket in the world, after two developed by the US and one by the EU.

"Heavier rockets are capable of lifting off more powerful geosynchronous satellites with multi-transmitting devices and a wider coverage of signal channels," Long said.

The Long March 5 rockets will be made in Tianjin.

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