For the first few months of 2021, the Martian atmosphere was buzzing withnew visitors from Earth.
First, it was the UAE Space Agencys Hope probe, followed by theChinese Tianwen-1 entering orbit.
To enter the Martian atmosphere, it will use a slightly different technique to previous missions.
Landing on Mars is notoriously dangerous more missions have failed than succeeded.
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This phase of the mission, known as entry-descent-landing, is the most critical.
Previous missions have used several different ways of Martian atmospheric entry.
Perfecting entry to Marss atmosphere has been helped by the experience of returning spacecraft to Earth.
Earth may have a significantly different atmosphere to Mars, but the principles remain the same.
A spacecraft orbiting a planet will be moving very fast, to keep itself bound to that orbit.
There are several ways to go about it.
Spacecraft are protected from the heat generated during atmospheric entry using heat shields.
But when it comes to Mars, engineers need to employ some additional measures.
This technique can also be used to lower the orbit of a spacecraft ahead of a landers atmospheric entry.
Since it uses the planets upper atmosphere to apply brakes, its called aerobraking.
Aerobraking has been used for various Mars missions includingExoMars Trace Gas Orbiterand theMars Reconnaissance Orbiter.
The blunt shape of the spacecraft alone is not enough to reduce the speed.
Previously, successful missions have used extra measures.
The Spirit and Opportunity rovers landed successfully on Marswith the same technique.
A few years later, theCuriosity roverused a new landing system.
This new system demonstrated the delivery of aheavy payload to Marsand paved the way for bigger missions.
Zhurong: the fire god
The Chinese Tianwen-1 rover landing is the next Mars mission.
In size, Zhurong falls between Spirit and the Perseverence and it is carryingsix pieces of scientific equipment.
Traditionally, the Chinese authorities dont reveal a lot of information before the event.
When it slows down enough, parachutes will be deployed.
In the last phase of the sequence, rockets with variable thrust engines will be used for further deceleration.
These will be used for navigational correction during its parachuted descent phase.
During the powered descent phase at the end, optical andLidar imagingwill assist in hazard detection.
Just before touchdown, an automated obstacle avoidance sequence will start to ensure a soft landing.
A few days after that, Zhurong will be ready to explore the surface.
