The Chinese made the first landing of their Tianwen 1 spacecraft on Mars. This happened on the night of May 15, at 2.18 Moscow time. On May 22, a descent from the lander of the six-wheeled Mars rover “Chzhuzhun” is planned, which will begin its journey across the Utopia plain. About how the Chinese chose this place, what new can be said by their scientific instruments in the three planned months of work – we talked about this with the independent space expert Igor LISOV.
– The Chinese launched their AMS (Automatic Interplanetary Station) in July 2020, like the Americans, but sat down a few months later. Why?
– The Americans did not have a goal to circle over Mars, they already have three working orbiters. Therefore, the project “Perseverance” was originally laid down that from the approach they will immediately go to land. And the Chinese chose a unique program, killing three birds with one stone: putting the spacecraft into orbit around Mars, carrying out a soft landing and working the rover on the surface. This has never been done before. Packing three missions at once into one with a mass of 5 tons is a truly non-trivial task.
– Why was Utopia chosen?
– According to the conditions of observation from the ground, according to their capabilities for constructing the descent trajectory of the AMC, the Chinese have allocated a zone from 5 to 39 degrees north latitude. Within its limits, it was possible to track the descent by ground means, that is, not to land blindly. Further, the density of the Mars atmosphere is very dependent on the height. To make the most of the parachute, you need a large depression in the Martian terrain. And if we draw a corresponding strip along the surface of Mars, we will see exactly three low-lying zones. If you list the possible places from west to east, the Chinese could poke their heads into the Amazon plain, where no one had ever sat down, or on the Chris Plain, but the American Viking-1 and Mars Pathfinder were already operating there. The third option was the Utopia plain, in the northern part of which Viking-2 conducted research, in the south-western part the Perseverance rover was operating, and between them – three thousand kilometers of unexplored territory. On this, in the end, the Chinese stopped. Thus, when choosing, two important parameters were taken into account – the latitudinal position on Mars and a sufficiently low place in terms of the relief to have time to slow down in a thin Martian atmosphere.
Help “MK” Utopia is a rounded lowland with a diameter of about 3300 km in the eastern part of the northern hemisphere of Mars. This appears to be an ancient impact crater.
– Despite the fact that the landing method was chosen as a classic one, the Chinese “parted” with a slight lag behind many American vehicles. Why did it happen?
– Usually, when talking about landing on Mars, American experts talk about “7 minutes of fear”, the program of Chinese scientists was 8 minutes, but actually the descent after entering the atmosphere of Mars took them 9 minutes. I think they will tell us more details later. Most likely, the Chinese device hovered for a long time at a height of 100 meters above the surface and “thought” where to flop.
– Are there unique instruments on board the lander and the rover and what results can be expected from them?
– In general, there is a fairly traditional set of instruments on the orbiter and on the rover: cameras, spectrometers, magnetometers, charged particle recorders, and a meteorological complex. There are, perhaps, radars for sounding the ground that stand out. In particular, the maximum working depth of the “sight” of the radar on the rover is up to 100 meters. If the American Perseverance is more focused on finding traces of life in samples of Martian soil and selecting them for subsequent delivery to Earth, the Chinese are still studying Mars in general and the landing zone in particular. Chinese scientists are interested in what minerals the planet’s surface consists of and whether there is ice there.
– Someone before the Chinese rover “looked” at 100 meters deep into Mars?
– As far as I know, no. On the American MSL 2012 (the Curiosity rover. – Auth.) there is a Russian device from IKI, from the group of IG Mitrofanov, but it “shines” only 2-3 meters deep into Mars. 100 meters is an application to understand if there are serious resources on Mars so that people can fly to it.
I remember that the Chinese initially wanted to explore Mars with us. Their first Red Planet exploration program was part of the Phobos-Grunt project. This device was supposed to deliver a small Chinese orbiter “Inkho-1” to Mars in 2012. But, alas, the device left orbit before reaching Mars.
Since then, in China, apparently, they realized that you can’t fly far with us, and decided to go their own way. The project “Inquiring Heaven” – this is how the name “Tianwen-1” is translated – proved that they can do it. However, Beijing is not at all averse to working with other space agencies as well. In particular, the Chinese have already agreed with ESA that at first they will relay signals from the surface of Mars not only through their orbiter, but also through the European Mars Express, which is now in orbit. How would Russia again not be left behind the board of progress, letting ahead of other planetary explorers.
Newspaper headline:
The Chinese are now on Mars
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