Written by Atharv Balaji, a grade 5 student
The China National Space Administration (CNSA) successfully landed their Mars rover, Zhurong, on the Martian surface on 15th May 2021. China is the only country after the USA to land a rover on Mars. The US has previously landed 5 rovers on Mars including their most recent Perseverance, earlier this year.
What is the Tianwen-1 Mission?
The spacecraft Tianwen-1, which means questions to heaven, was launched aboard the Long March-5 rocket on 23 July 2020.
In the early morning of 15th May 2021, at 4 am it separated into two parts, the landing module, and the orbiter. The landing module continued to fly towards the Martian atmosphere. At 7 am the craft entered the Martian atmosphere at the height of 125 km above the surface. The module needed a heat shield because the friction against the atmosphere will create heat.
Nine minutes of terror
Once in the Martian atmosphere, the module dropped the heat shield and deployed a parachute. Next, it unfolded its landing legs, dropped the parachute, and activated its retrorockets at 1.5 km. After landing at 7:18 am, the Zuhrong rover came out of the landing module into Utopia Planitia, a plain in the northern hemisphere of Mars.
This is called the nine minutes of terror because, in these nine minutes, the landing module is on its own and has to perform the maneuvers autonomously. Ground control on Earth is 320 million kilometers away and cannot remote control the landing.
Zuhrong is 1.85 meters tall and weighs 240 kgs. That is the size of a golf cart. It has 6 wheels and 4 solar panels and can move at the speed of 200 mph. Some of its instruments include a multispectral camera, a meteorological sensor, and ground-penetrating radar. The rover will have to overcome an array of difficulties on Mars, such as dust storms and disturbance in sunlight reception. The rover has been programmed to inactivate in extreme circumstances and reactivate itself when it is safe to do so.
The Tianwen-1 mission had 3 objectives:
- Orbiting Mars for comprehensive observations.
- Landing on the planet.
- Deploying a rover to conduct scientific operations.
This is not the first time that China has attempted to send a spacecraft to Mars. Their Yinghuo-1 mission in 2011 failed when it burned in the Earth’s atmosphere itself before even reaching Mars.
If everything goes well, Zuhrong will explore Mars for three months and the orbiter will orbit Mars for seven months.
UAE has also sent its ‘Hope Probe’ to orbit Mars. 2021 is an exciting year for Mars exploration.