BepiColombo Mission Hits First Milestone On Its Way To Mercury


The BepiColombo mission to Mercury is inching its way toward the solar system’s smallest and innermost planet. The European-Japanese spacecraft has just performed its very first maneuver in space, hitting the first milestone since it left Earth on October 19.

The intrepid probe — which is essentially a transport pod carrying two orbiters, as previously reported by the Inquisitr — has fired up its ion thrusters for the first time in space, conducting the inaugural test of its electric propulsion system, the European Space Agency (ESA) announced on Wednesday.

The BepiColombo transport module is powered by four ion thrusters that use electricity to positively charge xenon gas particles and create thrust, explains Science Alert. This is “the most powerful and high-performance electric propulsion system ever flown,” the ESA wrote, noting that — at full throttle — each of the four ion thrusters generates a force of 125 millinewtons.

While this may not sound like much — and is, in fact, “equivalent to holding an AAA battery at sea level,” as ESA points out — BepiColombo’s ion thrusters are currently working at maximum capacity. Unlike traditional thrusters that run on short chemical burns, the spacecraft’s electric propulsion system is designed for a series of 22 long-lived burns, each one lasting for up to two months.

“BepiColombo’s seven-year trip to Mercury will include 22 ion thrust arcs — and we absolutely need healthy and well performing thrusters for this long trip,” said Paolo Ferri, the ESA’s Head of Operations.

“Each thruster burn arc will last for extended periods of up to two months, providing the same acceleration from less fuel compared to traditional, high-energy chemical burns that last for minutes or hours.”

The test of the ion thrusters began as early as November 20, when BepiColombo fired up the first of its thrusters. The date was by no means an arbitrary one and was meticulously chosen to coincide with a rare window during which the spacecraft was in continuous range of communications with mission control.

“Electric propulsion technology is very novel and extremely delicate,” said Elsa Montagnon, the mission’s spacecraft operations manager. “This means BepiColombo’s four thrusters had to be thoroughly checked following the launch, by slowly turning each on, one by one, and closely monitoring their functioning and effect on the spacecraft.”

As BepiColombo fired each one of its four ion thrusters, giving off an electric-blue glow while it burned through the xenon propellant and generated blue plasma, the mission’s team analyzed the data to make sure everything was up to par.

The test was proclaimed a success and BepiColombo moved on to conducting its first space maneuver on December 2, when it fired up two of its four thrusters at the same time.

“To see the thrusters working for the first time in space was an exciting moment and a big relief,” said Ferri.

Two of BepiColombo's ion thrusters undergoing a joint test firing inside a vacuum chamber at QinetiQ in Farnborough, U.K.Featured image credit: QinetiQESA

As the Inquisitr previously reported, BepiColombo has a long journey ahead. The spacecraft will travel 5.6 billion miles and carry out nine planetary flybys — one of Earth, two of Venus, and six of Mercury — and 18 loops around the sun before it can finally reach its destination in 2025.

The first of the 22 electric propulsion thrust arcs is scheduled for mid-December and will steer the BepiColombo transport pod on the right track, adjusting its course in preparation for its first Earth flyby in April, 2020.

Artist's rendition of the BepiColombo spacecraft conducting a flyby of Earth.Featured image credit: ESA/ATG medialab