ESA’s Mars Express spacecraft and the Chinese rover Zhurong Mars completed in November a series of experimental tests on Mars: they are working on the development of a new communication system that could streamline the data flow between space missions and Earth.
ESA’s Mars Express conducted a series of experimental communication tests with the Chinese (CNSA) Zhurong Mars rover. The spacecraft successfully captured data sent “blind” by the rover on Mars and transmitted it to Earth, where it was sent to the Zhurong team in China. The researchers hope to conduct more tests in the future to continue experimenting and further improve this method of communication between space missions.
With missions under development or scheduled by all major space agencies, Mars has become the priority objective for mankind in space: in addition to the arrival of rovers and rovers, the coming decades are expected to see the landing of manned missions to the red planet and even the establishment of the first human colonies and bases.
But the terraforming or adaptation of Mars to human needs and to the characteristics of Earth also requires another key ingredient: communication between spacecraft, rovers and our planet. While on Earth communication is something so common and present since the digital revolution, on Mars the reality is different: its conditions and space climate require the creation of new technologies and tools.
One-way communication
Now, the European Space Agency (ESA) and its Chinese counterpart (CNSA) have begun testing a new technological scheme that could simplify and speed up data transmission between vehicles and spacecraft on Mars and from the red planet to Earth. According to a press release, during the month of November they successfully tested a one-way communication system that has not been used on Mars so far.
The landers and rovers collect data that seek to clarify various questions about the geology, atmosphere, environment, surface features, resources and potential for life on Mars. This information must be sent to Earth, so initially the rovers transmit the data to a spacecraft in orbit around Mars. Subsequently, the orbiters use much larger and more powerful transmitters to send the information through space to Earth.
The usual scheme is bidirectional: orbiters like Mars Express first send a signal to a rover, an initial greeting. Subsequently, the rover sends a reply to establish stable communications and begin the two-way exchange of information. However, for this scheme to work, the rover’s radio system needs to be compatible with that of the orbiter.
In this case, the communication frequencies used by the ESA orbiter are different from those used by the Chinese Zhurong Mars rover. Since two-way communication is not possible, the scientists and technicians imagined another alternative: Zhurong could transmit a signal using a frequency that Mars Express can receive.
Successful test
As the Mars Express relay radio has a mode that allows this one-way communication, the system has been successful: it is basically a “blind” communication, since the Chinese rover cannot check whether the message sent has actually reached its destination, as it cannot receive the replies from the European orbiter.
Beyond this limitation, the technique has passed several tests: the data sent by Zhurong Mars were captured by the ESA orbiter and retransmitted to Earth. The data reached ESA’s ESOC space operations center in Darmstadt, Germany, thanks to deep space communication antennas. It was then sent to Zhurong’s team at the Beijing Aerospace Flight Control Center in China, who confirmed the success of the test and the quality of the information received.
The new scheme could be efficient in these cases, especially considering that in the coming years Mars will receive “visitors” from different nations and continents, between which it is difficult to have total compatibility in terms of communication frequencies. Researchers are already working to improve the technique for the future.