China on Thursday took "another significant step" towards building a manned space station around 2020 with the successful launch of its second experimental space laboratory, U.S. space experts said.

"The launch of Tiangong-2 demonstrates China remains committed to human spaceflight and to the goal of building a space station in low earth orbit," Gregory Kulacki, senior analyst and China project manager at the U.S.-based Union of Concerned Scientists' Global Security Program, told Xinhua.

"The launch ... will help the Chinese space program further develop the technological capability to achieve that goal in the not too distant future," Kulacki said.

Former NASA astronaut Leroy Chiao, the first Chinese-American to be commander of the International Space Station, hailed Tiangong-2 as "another significant step" for China's human spaceflight program.

"I understand that Tiangong-2 is more advanced than Tiangong-1, and that the next crew (to be launched in October) will stay there for a month," said Chiao, also the first Chinese-American to perform a spacewalk.

"I anticipate that Tiangong-2 will test more advanced life support systems, as well as cargo ship docking and station refueling. This will set the stage for the launch of China's core space station module in 2018."

Chiao, who has visited China's space centers over the years, was impressed with the advances China has made, and revealed he has "good relationships" with several of the Chinese national astronauts.

"China is moving in a very deliberate and orderly fashion to advance their space capability," he said. "I think the technology is good, and they are moving to get more operational experience through Tiangong-2, before the beginning of space station construction."

Both Kulacki and Chiao highlighted the importance of international cooperation in space exploration.

"It is encouraging that China intends to solicit international participation in its space station project," Kulacki said.

"And my hope is that the United States and China will, at an appropriate time in the future, find a way to cooperate in the peaceful exploration of space instead of competing to turn it into a battlefield."

What Kulacki was referring to was a prohibition introduced in 2011 by the U.S. Congress that banned NASA, the country's space agency, from almost all direct interactions with China.

China was also barred from participating in the International Space Station, mainly due to objections from the United States.

Chiao stressed that international cooperation on human spaceflight is a common point of interest that helps improve overall relationships.

"The International Space Station is a great example of that," he said. "Many nations came together to build the amazing facility, and we are working together to further science. This helps to improve overall relations between the member countries."

Backgrounder: China's voyage to space BEIJING, Sept. 15 (Xinhua) - China's second space lab Tiangong-2 is scheduled to launch into space between September 15 and 20, according to the office of China's manned space program.

The space lab was transferred with its carrier rocket to the launch pad at Jiuquan Satellite Launch Center in northwest China on September 9.

Tiangong-2, which can enable two astronauts to live in space for 30 days, is capable of receiving manned and cargo spaceships and will be used for testing systems and processes for mid-term space stays and refueling.

It will also be involved with experiments on aerospace medicine, space sciences, on-orbit maintenance and space station technologies.

It has been 17 years since the program's first mission took place in 1999 with the launch of the Shenzhou-1.

China's manned space program facts:

Shenzhou-1
Launched: 6:30 a.m., Nov. 20, 1999

Landed: 3:41 a.m., Nov. 21, 1999

The main task was to examine the performance and reliability of the launcher and verify key technologies relating to capsule connection and separation, heat prevention, control and landing.

Shenzhou-2
Launched: 1:00:03 a.m., Jan. 10, 2001

Landed: 7:22 p.m., Jan. 16, 2001

Shenzhou-2 was the first formal unmanned spacecraft. The launch was conducted in conditions usually required for a manned spacecraft. It carried out several experiments in various fields of space, including life science, materials, astronomy and physics under conditions of microgravity.

Shenzhou-3
Launched: 10:15 p.m., March 25, 2002

Landed: 4:51 a.m., April 1, 2002

The module carried human physical monitoring sensors and "dummy astronauts." It was also equipped with escape and emergency rescue functions.

Shenzhou-4
Launched: 12:40 a.m., Dec. 30, 2002

Landed: 7:16 p.m., Jan. 5, 2003

The module was launched at a temperature of minus 29 degrees Celsius. Excessive harmful gas, found in the previous three crafts, was reduced to a safe level in the fourth module. Radiation-proof facilities and automatic and manual emergency rescue systems were installed on the spacecraft.

Shenzhou-5
Launched: 9 a.m., Oct. 15, 2003

Landed: 6:23 a.m., Oct. 16, 2003

The launch of the spacecraft was the first manned mission, which realized the nation's thousand-year dream of manned space flight and was a new milestone in China's space program.

The craft carried astronaut Yang Liwei.

Shenzhou-6
Launched: 9:00 a.m., Oct. 12, 2005

Landed: 4:33 a.m., Oct. 17, 2005

China's second manned spaceflight carried astronauts Fei Junlong and Nie Haisheng.

The mission aimed to master technology relating to a "multi-person and multi-day" orbital flight, as well as to carry out manned space-related scientific experiments and medical experiments.

Shenzhou-7
Launched: 9:10 p.m., Sept. 25, 2008

Landed: 5:37 p.m., Sept. 28, 2008

China carried out a historic first spacewalk by a Chinese astronaut. Zhai Zhigang, Liu Boming and Jing Haipeng were onboard.

Zhai left the cabin at 4:34 p.m. September 27, 43 hours after the craft launched, remaining outside the craft for 19 minutes and 35 seconds. China became the third country in the world to conduct extravehicular activity in space, following the Soviet Union and the United States.

Shenzhou-8
Launched: 5:58 a.m, Nov. 1, 2011

Docked with Tiangong-1 space module: 1:36 a.m., Nov. 3, 2011

Landed: 7:30 p.m., Nov. 17, 2011.

The return of the unmanned spacecraft Shenzhou-8 marked the end of the 49-day space docking mission, and it was hoped that it would pave the way for the establishing of China's own space station.

China not only made a breakthrough in space docking technology, but also validated the capability of its rocket, spacecraft and entire system, laying solid foundations for the building of a space station.

Shenzhou-9
Launched: 6:37 p.m, June 16, 2012

Docked with Tiangong-1 space module: around 2 p.m., June 18, 2012

Landed: 10:03 a.m., June 29, 2012

The return of the Shenzhou-9 spacecraft to Earth marked the end of a 13-day journey through space for three Chinese astronauts who completed China's first manned space docking.

The craft carried the first Chinese female astronaut Liu Yang.

It also marked the beginning of a new journey for China as it inched closer to its goal of building a space station.

Shenzhou-10
Launched: 5:38 p.m., June 11, 2013

Docked with Tiangong-1 space module: 1:18 p.m., June 13, 2013

Landed: 8:07 a.m., June 26, 2013

Shenzhou-10 was China's first application-oriented space flight. In its 15-day journey in space, Shenzhou-10 docked with the orbiting space lab Tiangong-1 twice, once through automatic operation and once manually.

The astronauts spent 12 days in Tiangong-1, where they conducted medical experiments, technical tests and delivered a lecture to students on Earth about basic physics principles.

Compared with the previous mission Shenzhou-9, Shenzhou-10 was not experimental but considered an applicable shuttle system for transporting astronauts and supplies to orbiting modules.

Tiangong-1:
Launched: 9:16 p.m., Sept. 29, 2011

Service end: earlier this year

The orbiting Tiangong-1 space module docked with Shenzhou-8, Shenzhou-9 and Shenzhou-10 spacecraft and undertook a series of experiments.

Source: Xinhua News Agency