Mars will be conquered by drones-sheets weighing with a fly

Engineers have developed extremely simple and cheap devices, each of which weighs a billion times less than any rover. These probes, more like sheets of paper, are designed to travel in the atmosphere of the Red Planet and other celestial bodies.

The development is described in a scientific article published in the journal Advanced Materials.

Recall that in the summer of this year, the Mars 2020 mission should go to the Red Planet. Within its framework, the first Martian helicopter, about which Vesti.Nauka (nauka.vesti.ru) was told in detail, will conquer the extraterrestrial sky.

There are no scientific instruments on board this apparatus. His task, it would seem, is extremely simple: to make the first flight in the atmosphere of Mars. Such caution of space engineers has a logical explanation: an "extremely simple" task can actually be incredibly complex and risky. And experts want to reduce the number of expensive systems that they risk.

The authors of the new concept offer a different solution. What if you release a fleet of incredibly simple and cheap devices into the sky of the Red Planet? Even if almost all of them fail, there will be at least some probes that have completed the mission.

“A Martian helicopter is very interesting, but still it’s just one machine, and it’s complicated,” explains Igor Bargatin, head of the research team from the University of Pennsylvania. “If something goes wrong, your experiment will end immediately, since nothing will be impossible to fix. We are proposing a fundamentally different approach: do not put all your eggs in one basket. "

Devices created by researchers do not have moving parts (namely, they are the most vulnerable spot of any equipment). The design is a plate literally assembled from hollow tubes. The material for them is aluminum oxide, and the thickness of their walls is only 50 nanometers.

The size of the device can range from a few millimeters to several centimeters. In the first case, the mass of the structure will be only 0.3 milligrams (approximately like a Drosophila fly). That is, it is millions of times lighter than the Martian helicopter (1.8 kilograms) and billions of times lighter than the Perseverance rover, which will carry it (1025 kilograms).

The "tubular" structure has two functions. Firstly, it makes the device much more durable than a continuous sheet of the same mass and dimensions (which is well known to corrugated cardboard manufacturers). And secondly, it serves as the engine for this "airplane carpet."

When one side of the structure is heated by sunlight or another source of heat, atmospheric gas filling the channels comes into motion. Flowing from one side, it breaks out from the other, acting as a jet stream. The thing is that the temperature of the channel wall changes throughout its length. This effect has long been known to physicists, but it has not yet been used to create any kind of aircraft.

The fact is that with the gravity and density of air familiar to us, the prototypes of such devices proudly hover at an altitude of half a millimeter. Not surprisingly, aircraft designers ignore this approach to conquering the skies.

However, atmospheric pressure on Mars is 170 times lower than on Earth. In such an environment, “Mars flights” can not only rise to a decent height, but also carry a load several times greater than their own weight.

This has already been shown in experiments. True, the pressure in the test chambers was even lower than on the Martian surface (10-200 pascals versus 600 pascals). But it should be noted that on the Red Planet the force of gravity is 2.6 times less than on the green.

But what is so tiny a probe can do? Given the continued success in miniaturization of electronics, not so little. The developers hope that the drones will carry sensors that determine the composition of the atmosphere. In addition, they could have an adhesive surface and collect soil particles on it (when planting or directly from the air). These samples could then be delivered to the rover for analysis.

Of course, in the latter case, the movement of these devices will have to be controlled. Theoretically, this is possible with the help of a laser mounted on the rover, which will heat the aircraft with the right intensity and in the right places. In practice, there are likely to encounter many difficulties. The controlled flight of an object resembling an autumn leaf is not an easy task. Especially on such a windy planet as Mars and even in automatic mode (manual control does not even make sense, because the radio signal would take several minutes to reach the Earth's antennas).

Nevertheless, the researchers are full of optimism. They dream of flying not only on Mars, but also on Pluto, as well as on the satellite of Neptune Triton. These are truly Napoleonic plans, given that no spacecraft have even entered orbit around Neptune or Pluto.

However, technology can also find a more mundane (in every sense) application. This is a study of the upper atmosphere of our planet.

Researchers would like to have measuring instruments there. The more knowledge we have about air movement at these altitudes, the better we can predict changes in the Earth’s climate and even weather, the scientist notes.