Wenchang (China) (AFP)

The rocket is in place and engineers are carrying out the final checks: China is launching a probe to Mars this week. A complicated mission, symbol of its growing space ambitions against the United States.

The launch should take place no later than Saturday from the tropical island of Hainan (south), famous for its beaches and 5-star hotels. But unfavorable weather or winds can further delay the event.

The Tianwen-1 mission ("Questions to the sky-1") will embark a probe made up of three elements: an observation orbiter (which will revolve around the red planet), a lander and a remote-controlled robot (responsible for analyzing the ground Martian).

These countries are taking advantage of the current reduced distance between Earth and the red planet. It is still around 55 million kilometers - the equivalent of nearly 5,000 Paris-New York round trips.

To travel this long distance, it will take about seven months for the Chinese probe, which is due to arrive in February 2021 in the gravity field of Mars.

Tianwen-1 is "similar to the American Viking missions of 1975-1976" in terms of "scale and ambition," Jonathan McDowell, astronomer at the Harvard-Smithsonian Center for Astrophysics in the United States, told AFP. United.

"I do not expect her to do anything significant compared to American achievements," he said, referring to the multiple probes and robots sent to Mars by NASA.

- 'Slower' -

Long away from the fierce USA-USSR space competition during the Cold War, the Asian country is patiently catching up.

He sent his first man into space in 2003, landed small robots (the "Jade Rabbits") on the Moon in 2013 and 2019, and just completed in June to set up the constellation of satellites of its Beidou navigation system - rival of the American GPS.

Its Martian mission is the next big step in its program, which also calls for the construction of a space station by 2022.

"The fact that China joins (in the conquest of Mars) will change the current situation which has been dominated by the United States for half a century," said Chen Lan, analyst at GoTaikonauts.com, specializing in the program. Chinese space.

"From the point of view of all of humanity, this is a positive thing."

In the opinion of experts, China's experience on the Moon will be very useful for Mars.

"But the much greater distance means (...) that we have to do things more slowly, because the round trip time of the radio signal is important", notes Jonathan McDowell.

"And we need a more sensitive station on Earth because the signals will be much weaker", he underlines, also pointing out the risks of failure during the trip.

- No direct -

In fact, of the forty or so Soviet, American, European, Japanese or Indian missions launched to the Red Planet since 1960, the majority have ended in failure.

In 2011, China had already attempted to conquer Mars with its Yinghuo-1 ("Firefly-1") probe placed in a Russian vessel. But the latter had suffered damage.

"As long as (the new probe) lands safely on the Martian surface and returns the first image, Tianwen-1 will already be a success," said Chen Lan.

Far from boasting, China is being cautious after registering some failures since early 2020, with failed launches and the missed return to Earth of a space capsule.

The Chinese media thus provide modest coverage of the preparations and the takeoff of the Long March 5 rocket that will take the probe to Mars should not be broadcast live on television.

© 2020 AFP