Europe is unsure whether its ambitious Mercury probe will be able to reach the planet

This week, the European Space Agency published a slightly ominous note about its BepiColombo spacecraft, which consists of two orbiters headed to Mercury.

the Online press release He pointed out that there was a “defect” in the spacecraft that weakened its ability to generate propulsion. The problem was first noticed on April 26, when the spacecraft’s primary propulsion system was scheduled to perform an orbital maneuver. Not enough electrical power was being delivered for the solar electric propulsion system at that time.

According to the space agency, a team including its engineers and engineers from its industrial partners has begun working on this issue. By May 7, they had made some progress, restoring the spacecraft’s thrust to about 90 percent of its original level. But this is not the whole trend, and the root cause of the problem is still not well understood.

This is an ambitious mission estimated to cost approximately $2 billion. Operation BepiColombo was carried out jointly by the Japanese space agency, JAXA, aboard an Ariane 5 rocket in October 2018. So, there’s a lot riding on these pushes. The crucial question is, at this energy level, can BepiColombo perform its primary mission of reaching orbit around Mercury?

The answer to this question is not very clear.

A three-part spacecraft

The spacecraft consists of three components. The “transport unit” is where the current problems occur. It was built by the European Space Agency and is intended to power the spacecraft’s other two components until October 2025. It is necessary to position the spacecraft to enter orbit around Mercury. The other two components of the mission are the European MPO orbiter and the Japanese Mio orbiter. After their planned arrival into orbit around Mercury in December 2025, the two probes will separate and conduct observations for at least a year, including characterizing the small planet’s magnetic field.

The press release is ambiguous about BepiColombo’s fate if it cannot restore full power to its propulsion system.

Ars reached out to the European Space Agency and asked whether BepiColombo could still reach orbit around Mercury in this case. The response, a statement from Elsa Montagnon, the space agency’s chief of mission operations, is not entirely clear.

“Thank you for your legitimate questions about the current uncertainty,” Montagnon said. “We are working hard to resolve these doubts.”

You must have delta-V

What is clear, she said, is that the current thrust level could support the next critical event, BepiColombo’s fourth swing of Mercury, which is scheduled to occur on September 5 this year. This is the first of three oscillations scheduled to occur in quick succession from September to January that will slow the spacecraft relative to Mercury.

“This swing sequence provides a braking delta of 2.4 kilometers per second and provides a change in the direction of the velocity vector with respect to the Sun as required for the end of the trajectory in 2025,” Montagnion said.

At present, a team of experts is working on the implications of reducing payments for the other two parts of this swing sequence and other payment needs in 2025.

This transfer module is scheduled to be jettisoned from the rest of the assembly in October 2025, after which the remaining Mercury approach and orbit insertion maneuvers will be performed using the European spacecraft’s MPO chemical propulsion subsystem.