• Earth and Mars are at their closest distance relative to each other every 26 months — and this is when Earthlings try to send missions to Mars.
• Every two years since the 1960s, different space agencies have sent missions to Mars. 

• Two out of the three missions launched for Mars last July are already operational. The UAE, a tiny but rich country of <10 million people, bedazzled the world by becoming the fifth national space agency (after the US, EU, Russia, and India) to reach Mars when the Hope Orbiter underwent orbital insertion on February 9. The UAE beat out China in the race for Mars, albeit by a day.
• The UAE mission will study the Martian atmosphere, and will seek to address the billion-dollar question of how and why Mars lost its atmosphere.
• The loss of the atmosphere resulted in the loss of surface water, and possibly the environment hospitable to life.

The Chinese experiment

• The Chinese National Space Agency arrived at Mars with lessons learned from a successful string of Chang’e missions to the Moon.
• Notably, the Chang’e 4 rover was able to survive more than 25 lunar nights (each night stretches to 14 Earth days) — this is a remarkable engineering feat, since temperatures can go down to –170 degrees C.
• The Chang’e 5 mission was able to successfully bring back rock samples to Earth in December 2020.
• Tianwen-1, the first mission to Mars from China, successfully underwent orbital insertion on February 10.
• Tianwen-1 carries an orbiter, a lander, and a rover. China’s approach for landing a rover is somewhat different.