All Systems Go for China's Blastoff to Mars

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A breathtaking solar eclipse that darkened the Yangtze River region in July was a celestial prelude for an upcoming flight to Mars and its largest moon spearheaded by China, Russia, the United States and the European Space Agency (ESA).

More than 50 researchers from the Chinese Academy of Sciences' Center for Space Science and Applied Research (CSSAR), the National Astronomical Observatory, the Shanghai Astronomical Observatory, and universities across the country are participating in the project to launch China's first Mars probe, the Yinghuo-1, aboard a Russian Zenith rocket.

The blastoff scheduled for October from the Baikonur Cosmodrome in Kazakhstan is expected to be an important step toward future Chinese expeditions to the moon and, possibly, a solo journey to Mars. If the international scientific venture succeeds, China hopes to move forward with plans for its own Mars probe in 2012.

CSSAR chief Wu Ji told Caijing, "There's a great deal of important work we can do."

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Sino-Russian Cooperation

China and Russia have been working together on space projects since the 1990s. The quest to learn more about Mars has strengthened their cooperation.

Chen Changya, assistant chief engineer for the Sino-Russian Mars probe and researcher for Shanghai Satellite Engineering Scientific Research Institute, told Caijing it's a mutually beneficial relationship. China wants to develop its space technology, and Russia needs a partner for space exploration.

China's original plan was to launch a Mars expedition in 2020, Chen said. But cooperation with Russia pushed China's schedule ahead 10 years and vastly increased rocketry know-how among Chinese scientists.

The upcoming expedition is called Phobos-Grunt. Phobos is the larger of Mars' two moons. "Grunt" means "soil" in Russian. In Greek mythology, Phobos was the son of Ares and Aphrodite and his name, which means "fear," was given to the Martian moon by its discoverer, astronomer Asaph Hall of the U.S. Naval Observatory in 1877.

After a 10-month flight, the Phobos vehicle is expected to begin orbiting Mars in August 2010 before releasing a Chinese-made satellite which includes a landing probe. The probe will orbit Mars a few months before eventually landing on the Martian moon, where it will collect soil samples. Those samples as well as results from an experiment focusing on life during interplanetary travel will then be returned to Earth

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If all goes as planned, the probe will return home between August 15 and July 20, 2012, with a sealed capsule containing soil samples from the Martian moon, which would be the second samples of extraplanetary lunar material ever collected – second only to samples taken from Earth's moon.

Collecting lunar samples from Phobos is easier than a similar procedure on the surface of Mars. That's because the planet's gravitational pull requires the expenditure of a huge amount of fuel to reach or leave the surface. But the gravitational pull of the Martian moon is only 6 percent as strong.

The biological test will determine whether living organisms can survive for extended periods of time unprotected in outer space, perhaps setting the stage for a future manned mission to Mars. The Finnish lander will release a weather balloon to explore the Martian atmosphere.

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Challenges Ahead

A Martian survey presents a definite challenge for China, which only recently surveyed the moon. For one thing, the distance gap is vast: Earth and Mars are at least 50 million kilometers apart, while the moon is only about 380,000 kilometers away. "China still doesn't have the ability to conduct deep space expeditions on its own," Wu said.

One challenge, Wu said, is that parameters for the Martian probe's orbital entry must be precise. Moreover, transmitting data to and from the probe through space will be difficult.

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Russia initially agreed to let Chinese machines carry a 110 kilogram payload, but later gave permission to add five kilos. That means China's mission will hinge on a small satellite.

The probe must circle the planet in a fixed, elliptical orbit around the Martian equator to conserve fuel, since there's no room on board for the extra fuel needed to change orbital paths.

Several scientific goals have been reported for Yinghuo-1. Its cache of scientific instruments will be responsible for exploring Mars' magnetic field and ionosphere; studying the planet's ion distribution, as well as the escape rate for atmospheric ions; looking at Martian topography, the terrain, and sandstorms; and studying Mars' gravitational field.

The atmospheric ion study is a focus for international Mars research. Previous expeditions discovered that a huge amount of oxygen escapes from Mars. If the escape rate can be determined, scientists could extrapolate theories about the amount of water that may have been on Mars in the past.

One of the probe's limitations makes gravitational study possible. Yinghuo-1 is not self-propelled and will travel in a large orbit, so it will face a variety of outside interference. Huang Chengli, a researcher at the Shanghai Astronomical Observatory, said observing irregularities in the probe's orbit will allow scientists to detect irregularities in Mars' gravitational field.

Yinghuo-1 has been undergoing final testing at the Lavochkin Science and Production Association facility in Moscow. So far, the results have been excellent.

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Designing a remote control system for Yinghuo-1 has and continues to be a key challenge for Chinese scientists. To cope, ESA agreed to work with China and Russia by allowing the use of European antennas to supplement Chinese communications antennas in Miyun, a county northeast of Beijing, and the Yunnan Province capital of Kunming.

Another difficulty will arise when Yinghuo-1 reaches apareon, which is a point in a Mars orbit when a satellite is farthest from the Martian surface. At that time, the satellite will enter a shadow zone, where it will be cut off from sunlight and subject to extremely cold temperatures that could freeze or damage instruments.

The instruments should be able to survive an orbital cycle that takes Yinghuo-1 in and out of apareon for about a year, Wu said. But completing all the project's scientific tasks will take about two years, which means the satellite will be pushing the envelope.

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Solo Goal

Some experts say China is more than 20 years away from launching a solo expedition to Mars. But Chen is more optimistic. He thinks cooperation with Russia has greatly increased China's technological capabilities in terms of remote control technology and communications, laying the groundwork for Chinese expeditions to Mars in the future.

Chen told Caijing that China, based on what its scientists currently know about probes and fuel technology, and along with a little in-house innovation, eventually will be able to reach Mars. He admits, however, that China is still working on improving its ability to develop space-related communications. Scientists now lack the necessary antenna equipment, although the situation should change by 2012.

China has yet to formulate a concrete plan for a solo Mars expedition. Scientists could develop a new spacecraft for close-range observations, but experts have not ruled out the possibility of modifying the country's Chang'e series of spacecraft for such a mission.

For now, China has no choice but to participate in international expeditions to Mars. These programs include some competitive aspects, but generally international cooperation in space exploration is all about mutual benefit, information sharing and efficiency to avoid research duplication.

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Augustin Chicarro, an official with the ESA's Mars Express Project, told Caijing that people worldwide are interested in exploring Mars, and that many countries are planning expeditions. He hopes, however, that ESA's project to develop a Martian surface vehicle called ExoMars will encourage countries to work together.

ExoMars was originally scheduled for launch in 2013 but has been postponed for the time being. Chicarro said the European Union originally allotted 850 million euros but, according to current estimates, at least 1.2 billion euros will be needed for its completion.

Chicarro said European program members would produce an orbiter and rover, while rocket and networking technology would be handled by the United States. Reportedly, Japan has expressed interest in joining the program, fuelling hopes that China will come on board as well.

何涵妃

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何涵妃

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