Madrid 2 (European Press)
The European Space Agency (ESA) Mars Express orbiter on Mars has conducted a series of experimental communication tests with the Chinese rover Zhurong, deployed in the Utopia Planitia region.
Mars Express successfully captured the data sent by the rover “blindly” and transmitted it back to Earth, where it was sent to the Zhurong team in China.
The Zhurong rover, piloted by the Tianwen-1 orbiter, directs its radio toward the Martian sky. At any moment, the European Space Agency’s (ESA) Mars Express will begin to fly overhead. Zhurong starts sending a signal into space. You have no way of knowing if your message was received.
Landers and rovers on Mars collect data that helps scientists answer fundamental questions about the geology, atmosphere, surface environment, water history, and potential for life on the Red Planet.
To bring this knowledge back to Earth, they first transmitted the data to a spacecraft in orbit around Mars. These orbiters then use larger, more powerful transmitters to “transmit” data through space to Earth.
“blind” communication
“An orbiter such as the European Space Agency’s Mars Express typically sends a hail signal to the rover as ‘hello,'” James Godfrey, Operations Director of the Mars Express spacecraft, said in a statement.
“Then the rover sends in response to establish stable communications and initiate a two-way exchange of information. But this depends on the rover’s radio system being compatible with the orbiter’s system.”
Because the Mars Express transmits its “hello” signal using communication frequencies different from those received by the Chinese Zhurong Mars rover, two-way communication is not possible. But in the other direction, Zhurong can send a signal using a frequency that Mars Express can receive.
The relay radio on the Mars Express has a mode that enables this one-way communication: a “blind” connection in which the transmitter cannot be sure that its signal has been received, but so far, the technology has not been tested on the spacecraft.
In November, the ESA’s Mars Express and Zhurong team conducted a series of experimental communication tests, in which Mars Express used this mode “blindly” to listen for signals sent from the Zhurong Rover. The trials culminated in a successful test on November 20.
“Mars Express successfully received the signals sent by the rover, and our Zhurong team colleagues confirmed that all data arrived at Earth with very good quality.” says Gerhard Peleg of the European Space Agency. “We look forward to more tests in the future to continue experiments and improve this method of communication between space missions.”
Data sent by Mars Express reached Earth at the European Space Agency’s ESOC Space Operations Center in Darmstadt, Germany, via deep space communications antennas. From there, this data was sent to Zhurong’s team at the Beijing Aerospace Flight Control Center, who confirmed the test’s success.