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China's First Spacewalk: A Prelude of Things to Come

(2008-06-24 20:08:39) 下一个
China\'s First Spacewalk: A Prelude of Things to ComeBy Leonard David, Special Correspondent, SPACE.com

posted: 24 June 2008 07:00 am ET
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Future flights of China’s Shenzhou spaceship will include space walks – a prelude to rendezvous and docking in Earth orbit. Image Credit: China National Space Administration.
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Future flights of China’s Shenzhou spaceship will include space walks – a prelude to rendezvous and docking in Earth orbit. Image Credit: China National Space Administration.

China launches its second manned spacecraft Shenzhou-6 at the Jiuquan Satellite Launch Center in northwest China\'s Gansu Province at 9:00 a.m. local time Wednesday, Oct. 12, 2005. Credit: AP Photo/Xinhua,Zhao Jianwei.

Chinese astronauts Fei Junlong, left, and Nie Haisheng wave before they walk to the launch tower at the Jiuquan Satellite Launch Center in northwest China\'s Gansu Province Wednesday, Oct. 12, 2005. Fei Junlong and Nie Haisheng were to carry out the space flight mission of China\'s second manned spacecraft Shenzhou-6 on Oct. 12. Credit: AP Photo/Xinhua,Zhao Jianwei.

A visitor walks past the model of China\'s first manned space craft Shenzhou V exhibited at the Science and Technology Museum Tuesday, Oct. 11, 2005 in Shanghai, China. China\'s second manned space mission will be launched this week, carrying two astronauts into orbit on a flight lasting several days, the government announced Tuesday. Credit: AP Photo/Eugene Hoshiko. GOLDEN, Colo. — China is stepping up and out in the world of space exploration.

Space officials in that country are readying the Shenzhou 7 spacecraft for an October sendoff, one that will carry a trio of their taikonauts into Earth orbit. The mission not only promises to strengthen China\'s human space travel agenda, but also provides a glimpse into actions to be undertaken in the future.

China has initiated a step-by-step approach in flying their taikonauts: The single-person Shenzhou 5 flight in 2003 of 14 orbits; the two-person voyage of Shenzhou 6 in 2005 lasting 5 days; and soon to head skyward, a threesome of space travelers. And on this flight, one of those space travelers is to carry out China\'s first spacewalk, also known as extravehicular activity, or EVA for short.

In some ways, the upcoming mission spotlights the hop, skip, and jump abilities of China in comparison to U.S. space history.

For the U.S., the Mercury series of single-seat flights led to the two-person missions of Gemini spacecraft, followed by sojourns of the Apollo three-person crew capsule. More to the point, in the U.S., the first human-carrying orbital flight of Mercury was in 1962; Gemini in 1965; and Apollo in 1968.

So is there a true measure of growth, albeit somewhat skewed given the driving nature of the Soviet Union versus the U.S. Moon race?

Case in point: If this next mission for China is successful in attaining orbit, that country will have taken something like a year less time to move from single-seat orbital flight to Apollo three-seat space travel - contrasted to U.S. human spaceflight progress in Earth orbit.

Learning curve

On one hand, China\'s steadfast evolution in human space treks is laudable. On the other, given that status card, leading spaceflight aficionados seem to sense different take-home messages.

Implications, as far as I can see...few, if any, said Joan Johnson-Freese, an analyst of China\'s space policy and Chair of the National Security Decision-Making Department at the U.S. Naval War College in Newport, R.I.

Johnson-Freese told SPACE.com that the U.S. Mercury program of the 1960s was spearheading research just to see if humans could swallow in space...or how the human psyche would react once in Earth orbit. There were lots of medical questions, she noted.

NASA\'s Project Mercury was quickly followed by a salvo of 10 human-carrying Gemini flights from March 1965 to November 1966. All-in-all, piloted Mercury and Gemini orbital outings tally up to 14 flights in five years, Johnson-Freese observed — and don\'t forget those two earlier and piloted suborbital Mercury missions.

Technology development was incremental because it was all new, but consistent, Johnson-Freese stressed.

The Chinese will have three flights with a successful mission next fall. They have been able to benefit from lots of lessons learned from both the Americans and the Russians. That is not to downplay the difficulty of the technology or the achievements of the Chinese...they just have the luxury of starting much higher on the learning curve, she concluded.

Pow...pow...pow

Given the years of mastering human space travel, is China\'s blossoming to-do list in order to operate in Earth orbit worth spotlighting?

Yes, absolutely...it is worth flagging, said Dean Cheng, an Asian affairs specialist at the U.S.-based Center for Naval Analysis in Alexandria, Virginia.

Now, the flip side to that, of course, is that it has also been done before. So it\'s not like they need to engineer everything from scratch, Cheng told SPACE.com, adding that China can depend on designs similar to those proven to work by the U.S. and former Russians. But, yes, it is nonetheless impressive.

Cheng points out, however: The main difference ...there were more Mercury and Gemini flights in the intervening period. What is interesting about the Chinese effort is that they are doing it with so few flights. Four unmanned flights...then pow-pow- pow...one-man, two-man, three-man/EVA.

Cheng also underscored the built-in danger to nations that ramp up human spaceflight expertise. Both the U.S. and the Soviet Union lost people during their respective run-ups.

You have to wonder if the Chinese can sustain a perfect space record, he added. Obviously, one hope\'s that they can.

Take-away knowledge

In terms of where China is really headed in human spaceflight, crystal ball gazing is not easy.

Stacking up their one-two-three punch in the field of human spaceflight against U.S. space program heritage doesn\'t quite match up, said Roger Launius, senior curator for the Division of Space History at the Smithsonian Institution\'s National Air and Space Museum in Washington, D.C.

Learning what China needs to know about conducting a lunar trip, probably a circumlunar trip, on three missions seems a bit thin to me, Launius told SPACE.com.

While Mercury, Gemini, and Apollo programs might have been exceptionally cautious — and thus took more time and a greater number of missions than the Chinese effort — the knowledge return from the American programs versus China\'s three flights cannot be anywhere near each other, Launius explained.

Let\'s take the Gemini program, Launius said. A central reason for it was to perfect techniques for rendezvous and docking, EVA, and long duration flight. Assuming that these same skills will be required in a Chinese moon program, and I believe they will, where will the knowledge and experience for them come from in these three missions?

Launius said that the Gemini flights swamp China in terms of demonstrated skills. The country has yet to rack up the experience base of spacewalking, rendezvous and docking that is now standard in the U.S. and Russia, he added.

A core question, it seems to me, is this: Will ground simulation be able to compensate for the lack of orbital experience? Launius said. Perhaps, but I\'m not sure.

More acclaim than deserved?

Stepping back and taking a larger look at where China\'s human space program is headed, Launius observed: Personally, I think the Chinese program is moving forward at a modest pace and is getting a lot of mileage out of the fact that it is a secret effort that forces us to speculate about it. It is receiving among the space community more acclaim than I think it deserves.

Launius said that there\'s enough in China\'s statements on future manned moon missions to fuel Western speculation that the country has a vast program, immensely capable, and seeking to at least equal the Americans in a Moon program of its own.

There is no official Chinese evidence to support the concept of a Chinese human moon program, despite the wishes of some inside the Chinese space program who would love to do it. Occasionally, someone will say something about this to Western media but official documents available do not say anything about such a program, Launius said.

There are those in the U.S. space community that would like to see China hell-bent on sending taikonauts onto the moon\'s surface, Launius said, because they believe it would spark a new space race. I\'m not sure that would be the outcome of these Chinese efforts...but I also see no evidence for serious Chinese efforts in that direction, he added.

Picking up speed

Meanwhile, preparations to launch Shenzhou 7 are picking up speed in China.

According to Chinese news services, the spacecraft has undergone modifications to accommodate an airlock. A spacewalking-qualified space suit has been okayed for flight. There have been extensive checkouts of the craft to fulfill its mission objectives.

What day the three-person crew takes off from the Jiuquan Satellite Launch Center on its Long March booster in October is yet to be announced. Earlier, there has been comment about broadcasting the spacewalk live on television.

Moreover, the spacewalk mission — and the duties to be performed during the EVA — has been deemed as crucial for China to make possible a space laboratory or station in Earth orbit.

Earlier this month, it was noted that six taikonauts had been selected for the upcoming mission from 14 candidates — a crowd that included Yang Liwei, China\'s first space explorer who flew solo on Shenzhou 5. For Shenzhou 7, three will fly the actual mission with the others tagged as substitutes.

Also, Yuanwang 6, an ocean-going tracking ship, has been delivered for service in Shanghai to participate in the Shenzhou 7 flight and to assist in the slated spacewalk. It joins sister ship, Yuanwang 5, to take part in maritime space surveying and mission controlling operations.

Qi Faren, academician of the Chinese Academy of Engineering and researcher of China Spaceflight Technology Research Institute — credited as chief designer of China\'s first five Shenzhou spaceships and chief consultant for Shenzhou 6 and Shenzhou 7 - has been quoted as saying that plans are already underway for Shenzhou 8 and Shenzhou 9. He added that the intervals between each launch will become shorter.

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