All-seeing eye: new engines will allow to build giant antennas in space

Russian engineers have developed a gas engine for nanosatellites, which will increase the maneuverability of spacecraft and allow them to be combined into multi-satellite groupings. Such systems can be used, for example, to create distributed antennas and space observatories. In addition, they will allow obtaining stereo images of the Sun in real time, which will increase the accuracy of forecasts of space weather and magnetic storms on Earth. However, for now these are the technologies of the future: modern nanosatellites have limited functionality, experts emphasized.

How a gas-powered engine will increase the range of spacecraft

Scientists from the Moscow Aviation Institute (MAI) and Samara National Research University named after Academician S.P. Korolev have created an engine for nanosatellites that runs on gas. One of the advantages of the system is its flexible layout: the gas tank can be placed in any free cavity of the spacecraft and connected by tubes to the propulsion system. This will increase the supply of working fluid on board and, consequently, the duration of maneuvers.

Such characteristics will expand the capabilities of nanosatellites. The devices will be able to combine into complex distributed systems, such as multi—component observatories for observing solar flares and black holes, as well as searching for signs of life on exoplanets.

Active "constellations" of nanosatellites can also be used for high-precision remote sensing of the Earth: tracking cyclones, forest fires, volcanic eruptions and ice drift, as well as monitoring the movement of vehicles and cargo.

— Modern space technologies are increasingly relying on small technical devices. Jet engines make it possible to increase the functionality of small satellites by increasing their maneuverability, as well as prolong their life in orbit, compensating for deceleration in the upper atmosphere. However, strict restrictions on weight, volume and onboard power complicate the placement of such power plants on small satellites, " said "Izvestia" senior engineer of MAI Svyatoslav Gordeev.

The new device is a pulsed plasma engine, he explained. Such units use electrical energy to create thrust by accelerating plasma — ionized gas — in a strong magnetic field. The installation is designed for nanosatellites weighing up to 10 kg.

The design is based on a high-speed solenoid valve with a thin movable diaphragm made of magnetic material. When a short current pulse is applied, the electromagnet creates a field that squeezes the membrane and lets a portion of gas into the engine channel. Then the pressure of the medium returns it to its original position.

According to the developer, this principle ensures high performance with low power consumption. The absence of friction elements, in turn, increases the reliability and durability of the mechanism.

— According to calculations and experimental data, the frequency of gas supply pulses in the new installation in space will be 1-2 Hz. The engine will be able to withstand more than a million valve opening and closing cycles without degradation of the main mechanisms, which allows the orbiters to perform up to 300 hours of active maneuvers," the scientist said.

Such characteristics will make it possible to solve a wide range of practical problems in near-Earth space. In particular, the engine can be used to distribute nanosatellites into target orbits after launch and adjust their position as part of large groupings, he added.

How satellite networks can help monitor the movements of vehicles

— The transition from single objects to network structures is a modern trend, including in satellite construction. A large number of simple devices connected to a network are able to solve tasks that were previously performed by large research complexes more flexibly and more cheaply. With the current level of technology, mass production of many simple devices is more efficient than creating one complex and high—tech product," Leonid Kessarinsky, director of the Academic Research Center for Information Security of Systems and Networks at the National Research Nuclear University MEPhI, told "Izvestia".

According to the expert, the institute has developed a new test complex in this area — a "simulator" of onboard computers of nanosatellites. It was presented at the pre-conference of the "Microelectronics" forum on trusted technologies. The equipment allows you to reduce the testing time of the devices from eight weeks to 40 hours.

— Distributed systems can significantly improve the quality of remote sensing of the Earth. A large number of spacecraft in orbit makes it possible to better track the movement and changes of objects than a single satellite. It works like a faceted eye of a fly, in which each cell conducts surveillance independently of the others," explained military expert Dmitry Kornev.

According to him, groupings, including those consisting of nanosatellites, are better protected from system failure, since they can implement duplication of tasks between devices. Disposal or destruction of some of them will not lead to disruption of the system. The image quality may decrease, but it will remain at an acceptable level.

How to get a stereoscopic image of the Sun

— Multi-satellite configurations will allow creating giant observatories with a "mirror" of thousands and millions of kilometers. They will work according to the principle of interferometry: when a multitude of small telescopes or antennas spaced apart combine into a single system and provide angular resolution that is unattainable for a single device. In the future, such systems will help to explore remote objects, for example, to check exoplanets for traces of life," explained astrophysicist and popularizer of science Vladimir Afanasyev.

According to the scientist, such solutions can also be useful for detecting gravitational waves. This is particularly important for studying supermassive black holes in the centers of galaxies. For such systems to work, it is necessary to hold all the elements in strictly defined positions, and new engines can provide the required accuracy.

In addition, many small satellites located around the Sun will be able to receive stereo images of the sun in real time, Vladimir Afanasyev noted. This will expand the possibilities of forecasting space weather and magnetic storms on Earth.

— The development is useful for prolonging the active existence of spacecraft. However, when studying the Sun, it does not solve the problem of the lack of specialized missions. Let me remind you that Russia currently does not have a single spacecraft for these purposes. As a result, domestic heliophysicists are forced to use foreign materials," said Sergey Yazev, a leading researcher at the Institute of Solar—Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences, Director of the Astronomical Observatory of Irkutsk State University.

In the future, when spacecraft will be able to work as elements of a single "mirror", such technology will be especially in demand. However, today nanosatellites are capable of solving only a limited range of tasks, the expert concluded.