The ESA/JAXA BepiColombo mission has performed its second gravity assist of the planet Mercury, capturing new close-up images as it approaches the planet’s orbit in 2025.
Closest approach occurred at 0944 UTC on June 23, 2022, about 200 km above the planet’s surface. Images from the spacecraft’s three monitoring cameras (MCAMs) were collected during the encounter, along with scientific data from a number of instruments.
“We have completed the second of six Mercury flybys and will return next year for the third before reaching Mercury orbit in 2025,” Emanuela Bordoni, ESA’s BepiColombo deputy director of spacecraft operations, says in a statement. .
Because BepiColombo’s closest approach was on the night side of the planet, the first images illuminating Mercury were taken about five minutes after approach, at a distance of about 800 km. Images were taken for about 40 minutes after close approach as the spacecraft moved away from the planet again.
As BepiColombo flew from nightside to dayside, the Sun seemingly rose above the planet’s cratered surface, casting shadows along the terminator, the boundary between night and day, and highlighting the topography of the terrain in dramatic fashion. .
The images show beautiful details of Mercury, including the Heaney crater, 125 km wide and covered with smooth volcanic plains. It harbors a rare example of a candidate volcano on Mercury, which will be a major target for BepiColombo’s high-resolution image set once in orbit.
Just minutes after closest approach and with the Sun shining from above, Mercury’s largest impact feature, the 1,550 km Caloris Basin. wide came into view for the first time, its highly reflective lavas on its floor making it stand out against the dark background. The volcanic lavas in and around Caloris are thought to postdate the formation of the basin itself by about a hundred million years, and measuring and understanding the compositional differences between them is an important goal for BepiColombo.
“The images from Mercury flyby 1 were good, but the images from flyby 2 are even better,” said David Rothery of the Open University, who leads ESA’s Mercury Surface and Composition Working Group and is also a member. of the MCAM team. “The images highlight many of the science goals we can address when BepiColombo goes into orbit. I want to understand the volcanic and tectonic history of this amazing planet.”
BepiColombo will be based on data collected by NASA’s Messenger mission that orbited Mercury between 2011 and 2015. BepiColombo’s two science orbiters, ESA’s Mercury Planetary Orbiter and JAXA’s Mercury Magnetospheric Orbiter, will operate from complementary orbits. to study all aspects of the mysterious Mercury, from its core to surface processes, magnetic field and exosphere, to better understand the origin and evolution of a nearby planet. to his mother star.
Although BepiColombo is currently in a ‘stacked’ cruise configuration, which means that many instruments cannot be fully operated during the brief flybys, they are still able to obtain information about the magnetic, plasma and particle environment around the spacecraft, from places that are not normally accessible during an orbital mission.
BepiColombo’s primary science mission will begin in early 2026. It uses nine planetary flybys in total – one on Earth, two on Venus and six on Mercury – along with the spacecraft’s solar electric propulsion system, to help target Mercury’s orbit. Its next flyby of Mercury will take place on June 20, 2023.