Mars One, Ready for Launch!
Author: 白書
Reviewers: 蜗牛; 一毫秒的永恒
Note: “Mars One” was later officially renamed “Tianwen-1.” It successfully completed the three major stages of Mars exploration: orbiting, landing, and roving.
On October 11, 019, the China Aerospace Science and Technology Corporation published photographs of the physical spacecraft for China’s second Mars probe on its official Weibo account. It was the first time the public had seen the probe in its finished form; the mission was scheduled for launch the following year.
According to Ye Peijian, chief scientist for space science and deep-space exploration at the China Academy of Space Technology, a subsidiary of the China Aerospace Science and Technology Corporation, preparations for China’s Mars mission were complete and the launch was planned for 2020. The probe was provisionally named “Mars One” (and was later officially renamed “Tianwen-1”). The mission would carry an orbiter, a lander, and a rover, completing three stages at Mars: orbiting, landing, and roving. First, it would conduct global observations of the entire planet; second, it would land on Mars; and third, the rover would deploy and survey the surface. Under the plan, Tianwen-1 would travel to Mars aboard a Long March 5 launch vehicle in July 2020 and land near the Martian equator before the centenary of the founding of the Communist Party of China in July 2021.
The latest progress in China’s Mars program was exciting, but the country had already attempted one unsuccessful Mars mission: Yinghuo-1. Here, we look back at the probe’s ill-fated life.
Yinghuo-1 measured about 75 centimeters in both length and width and 60 centimeters in height. Its two deployed solar panels spanned approximately 7.85 meters. The probe had a mass of 110 kilograms, a designed operating life of two years, an average power output of 90 W, and a data-transmission rate of 8,192 bit/s. It carried four types of payload: a plasma-detection package, an optical imager, a fluxgate magnetometer, and a radio-occultation receiver. It was intended to spend one year observing Mars from orbit. Its objectives included studying the planet’s magnetic field, ionosphere, particle distributions, and the ways they change; measuring the escape rate of ions from the Martian atmosphere; surveying Martian terrain, landforms, and dust storms; and investigating the gravitational field around the Martian equator.
Yinghuo-1 was originally scheduled to launch with Russia’s Phobos-Grunt spacecraft aboard a Zenit-2SB launch vehicle from the Baikonur Cosmodrome in Kazakhstan in October 2009. On September 29, 2009, however, Russia postponed the launch until October 2011 to further ensure the project’s reliability.
On November 9, 2011, Yinghuo-1 launched together with Russia’s Phobos-Grunt probe and soon entered Earth orbit successfully. Three engine burns were then supposed to send the two probes onto a Mars-bound trajectory. The entire journey was expected to take about 300 days.
After launch, Yinghuo-1 remained mounted on Phobos-Grunt, and the two were to enter Mars orbit as a combined spacecraft. Yinghuo-1, installed atop Phobos-Grunt, would separate after three orbits of Mars. Phobos-Grunt would transfer into a circular Martian orbit, wait for an opportunity to land on Phobos, collect soil samples, and return them to Earth. Yinghuo-1, meanwhile, would carry out its Mars mission in a highly elliptical orbit with a periapsis of 800 kilometers, an apoapsis of 80,000 kilometers, and an inclination of less than 5°.
The day after launch, however, Vladimir Popovkin, head of the Russian Federal Space Agency, announced that Phobos-Grunt had failed to change orbit as planned. “It has been a very difficult night,” he said. “For a long time we could not locate the spacecraft. We eventually established its position and found that its propulsion system had not operated; both engine burns had failed.” This also meant that China’s first Mars-probe mission had ended in failure.
On January 15, 2012, Alexei Zolotukhin, a spokesperson for the Aerospace Defense Forces of the Russian Ministry of Defense, told the media that debris from Phobos-Grunt would fall into the Pacific Ocean at around 21:45 Moscow time (01:45 Beijing time on January 16). According to information from the Space Surveillance Center of the Aerospace Defense Forces’ Space Command, the unburned debris—about 200 kilograms—ultimately fell into the Pacific Ocean 1,250 kilometers west of Wellington Island, an island in southern Chile.
The Yinghuo-1 mission had long since ended, but new explorers were ready to depart. Because of the relative positions of Earth and Mars, a transfer window between the two planets opens only once every 26 months. The next window would arrive in 2020, setting off another wave of Mars missions. The year 2020 was set to be a major one for Mars exploration: NASA’s Mars 2020, China’s Mars One, and the ESA/Roscosmos ExoMars mission would all head for the planet.
Yinghuo-1 was designed only to operate in orbit. The new Mars One mission, by contrast, would complete all three stages—orbiting, landing, and roving—in a single mission, something never before attempted anywhere in the world. It undoubtedly carried greater risks, but it also offered greater opportunities. May China travel ever farther across Mars, and may China’s space explorers venture ever farther into space!
References
- Spaceflight Enthusiasts website
- People’s Daily Online
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