A chief designer with China's second lunar probe project has said that the country's lunar pursuit, while lagging behind Russia and the United States for more than 40 years, is still important because space exploration is part of the country's responsibility towards mankind.

"The most fundamental task for human beings' space exploration is to research on human origins and find a way for mankind to live and develop sustainably," said Qian Weiping, chief designer of the Chang'e-2 mission's tracking and control system.

Chang'e-2 blasted off on a Long-March-3C carrier rocket from the Xichang Satellite Launch Center, in southwest China's Sichuan province, at about 7 p.m. Friday.

"As a major country, China has the responsibility to participate in the activities of outer space for peaceful use and make its own contributions," Qian said.

Chang'e-2 is China's first unmanned spacecraft to be boosted from the launch site directly to the earth-moon transfer orbit, vastly reducing the journey time from that of its predecessor, Chang'e-1.

To acquire more detailed moon data, Chang'e-2 will enter a lower lunar orbit about 100 km above the surface, compared with the 200-km altitude of Chang'e-1, according to the control center.

Qian pointed out that China's pursuit of lunar probes and manned space flights was more out of a sense of responsibility than the need to follow in the footsteps of other countries.

"Once our mind is made up, we will do it no matter how many years later," Qian said. "However, we can never go beyond scientific rules and find a shortcut."

"What we're doing now is what some others already did 40 years ago. But that doesn't necessarily mean that we're lagging behind by 40 years," Qian said, adding that the country's levels of telecommunication, networks and scientific understanding, based on the progress in science and technology, were much more advanced than what they were decades ago.

"And we will shorten the gap fast," he added.

Some 40 years ago, Russia and the United States were the only countries to have sent people into space. During the U.S. Apollo 11 mission in 1969, Neil Armstrong became the first person to walk on the moon.

Qian said that China's space talents were outstanding and young. The average age of the design team for the country's manned project and lunar probe project was just a little over 30 years old, he added.

China launched its first lunar probe, Chang'e-1, in October 2007, marking a milestone in the country's space exploration journey.

Qian noted that a lunar probe was only the first step in China's quest for deep space exploration.

"We will walk on this road step by step -- scientifically and gradually," he added.