BepiColombo flew past Venus Satellite with measuring instruments from TU Braunschweig on course for Mercury

On the morning of 15 October 2020, the BepiColombo satellite passed by Venus to adjust its trajectory for its journey to Mercury. Magnetometers from Technische Universität Braunschweig measured the interaction of the solar wind with Venus.

Anyone who watched the morning star at six o’clock in the morning on Thursday will have unknowingly spotted a traveller with measurement technology from Braunschweig in the sky. The BepiColombo probe has completed another stage on its journey to Mercury, passing by Venus and continuing to adjust its course towards its target planet. The probe team from the European Space Agency (ESA) and the Japanese space agency JAXA approached Venus at a speed of about 37 km/s and came within 10,000 kilometres of the planet. After the celestial braking manoeuvre, BepiColombo’s speed was about 34 km/s.

This encounter also leaves tiny traces on Venus: Venus’ orbital speed is increased by one quadrillionth of a per cent as a result of the flyby, shortening the Venusian year by a tiny fraction.

During the flyby, the Braunschweig-based magnetometers of the Institute of Geophysics and Extraterrestrial Physics (IGEP), in cooperation with the Space Research Institute in Graz, were permanently activated. They listened carefully to measure the magnetospheric tail of Venus. This data then travelled some 170 million kilometres to Earth. Even at the speed of light, it takes about ten minutes. The researchers at TU Braunschweig will be busy analysing the data for some time to come.

Next year will see more entries in the cosmic wanderer’s stamp book: another Venus flyby in August and even the first of six Mercury flybys in October 2021, when researchers led by Dr. Daniel Heyner, who heads the magnetometer team at IGEP, will be able to analyse eagerly awaited data from Mercury’s magnetosphere. “We will finally be able to collect data from Mercury’s southern hemisphere and continue to piece together the magnetic map of this planet,” says Dr. Heyner.

Close European-Japanese cooperation

The European Space Agency (ESA), which was also responsible for the development and construction of the Mercury Planetary Orbiter (MPO), has overall responsibility for the mission. The Mercury Magnetospheric Orbiter (MIO) was contributed by the Japanese space agency JAXA. This second satellite is also equipped with magnetometers, for which IGEP is cooperating with Japanese institutes. The German contribution to BepiColombo is mainly financed by the DLR Space Administration with funds from the Federal Ministry for Economic Affairs and Energy (BMWi). In the past, scientific exchanges between Europe and Japan took place regularly in person. In times of corona, scientists have to meet virtually. “We are carrying on under difficult conditions and are waiting for better times when it will be possible to meet our Japanese colleagues in person again,” hopes Dr. Heyner.