Tianwen-1, which translates as Questions to Heaven, is China’s first Mars mission. The rover landed on Mars surface in May 14, making China the second nation that successfully sent a rover on Mars, after the US. But while China’s spacecraft arrived on the red planet later than the US, their preparedness and the scale of the operation exceeded NASA’s mission.
Tianwen-1 entered the Martian orbit seven months after launching. After that it spent about three months scanning the Mars surface for a landing location. The rover landed on a vast Martian plain called Utopia Planitia. There is scientific evidence showing that this area of Mars used to be an ocean, which will increase the chance of finding water.
The 240 kg, 1.85 tall rover is named Zhurong, after an ancient Chinese fire god. Zhurong is designed to last at least three months. It is equipped to study the planet’s geology, soil, and most importantly to search for water and new kinds of life. Its radar can scan 100 m under the Martian surface, searching for water pockets. Zhurong also has a high resolution camera on it, which will help it capture plenty of stunning images of the red planet. Instead of using a robotic arm to collect samples like the US Curiosity, the Chinese rover uses Laser-induced breakdown spectroscopy, a tool that uses laser pulses to atomize and excite samples.
This is a huge leap for China National Space Administration (CNSA). Tianwen-1 is one of only a small number of successful Mars landers, and it succeeded on the first attempt. There had been 44 attempts to explore Mars as of June of 2020 and although not all were landing attempts, more than half of them failed. Issues have included signal delay, the thinness of the Martian atmosphere that makes aerobraking less effective. The durability of the communication components is another factor. Most spacecraft made it to Mars but they were unable to send the signal back to Earth.
Before sending Tianwen-1 to Mars, CNSA has done many space missions. China successfully sent their first astronaut to space with the Shenzhou spacecraft in 2003, becoming the third country in the world to send humans out to space, only behind the United States and the Russian. In 2007, CNSA sent their first unmanned spacecraft to the moon. The Chang’e lunar orbiter, weighing more than 5,000 pounds, reached the moon’s orbit 12 days after launch. Chang’e is a part of China’s moon exploration program, also marking China’s first deep space mission.
In 2013, the third Chang’e mission, landed a rover on the moon’s surface. This made China the third nation to achieve a moon landing after the US and the USSR. China launched the Tiangong space laboratory in 2016, and intends to create a manned station in 2022. In 2020, one of the most impressive achievements of China’s space agency was to launch the Beidou navigation satellite. This navigation system of China has been under the making and developing for many years so it can directly challenge the US Global Positioning System (GPS). In the same year, the Chinese government managed to send an uncrewed mission to the moon, to collect material and study the moon’s origin.
Despite more than a decade of space exploration, the CNSA still encountered many challenges on their way to the red planet with Tianwen-1. The first challenge was the distance between our planet and Mars, which ranges widely from 54 million kilometers at the closest to 400 million kilometers at the furthest. With these enormous distances, the communication signal will be delayed by 10 minutes. According to Pang Zhihao, former researcher at the China Academy of Space Technology and Space Science, China’s space agency will have to send their instructions in advance to adjust the attitude of the spacecraft. During this process one mistake could lead to critical failure of the whole operation. If the braking burn is too slow, the spacecraft will crash down to Mars, and if it is too fast it will miss the landing location.
Energy is another issue, because the Mars orbit is further from the sun than the moon, therefore the solar panel on the spacecraft will have more difficulties in absorbing energy. Also there are multiple unknown factors the CNSA has to deal with because this is their first time operating a spacecraft on the Martian surface.
Zhurong has spent its first 3 days away from the lander to explore the surrounding area, according to China Space News. The rover doesn’t travel more than 10 meters a day because the experience and information of Mars is still limited, according to Jia Yang, an engineer and a member of Chinese Mars exploration program. Nonetheless, the pace of the mission will be increased in the future, Yang added. After Tianwen-1, China has many new plans for deep space exploration. One of them is Asteroid exploration mission that will be launched around 2022-2024. Not just that, the CNSA is planning to return to Mars for a sample collecting mission in 2030. China even wants to explore the Jupiter system by sending an orbiter, expected to arrive at Jupiter around 2036.
The presence of China on Mars will not just help gather more information for the scientist, but create a higher probability of international collaboration in planetary exploration in our solar system. “Many of the greatest challenges for planetary science in the coming decades will require international cooperation,” said David Flannery, a member of NASA’s Perseverance engineering team.
Image credit: CNSA