The Mercury-linked BepiColombo spacecraft took its second look at its target planet today during a super-close flyby designed to slow the spacecraft and adjust its trajectory.
Bepi Columbus is a joint mission of the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA). The mission, made up of two orbiters traveling to Mercury stacked on top of each other, released in orbit around the Sun in 2018. Since then, ground controllers have been adjusting the spacecraft’s trajectory through a series of nine flyby maneuvers (one on Earth, two on Venus and six on Mercury), to gradually slow down of the BepiColombo so that it can enter orbit around the solar systeminnermost planet of 2025.
The June 23 flyby was BepiColombo’s second flyby of Mercury, after the probe first encounter with the planet in October 2021. The spacecraft made its closest approach to Mercury’s surface at 5:44 am EDT (0944 GMT), when it passed just 200 kilometers from Mercury’s cratered surface, closer than the two orbiters will operate once the mission start seriously.
Related: Mercury looks stunning in this first flyby photo of the BepiColombo mission of Europe and Japan
The spacecraft was taking images of the burned-out planet during the flyby with its low-resolution monitoring cameras mounted on the spacecraft’s transfer module. ESA released the first image about four hours after the closest approach, revealing large impact craters, including a 200 km wide basin.
The two orbiters together carry 16 science instruments, but only about 60% of them were operational during the 48 hours around the closest approach, ESA’s BepiColombo project scientist Johannes Benkhoff told Space.com via email. The rest, including high-resolution cameras, cannot be operated in the cruise configuration, as they are hidden by the spacecraft’s transfer module or its sun shield.
Benkhoff said the spacecraft’s magnetometers and particle detectors were turned on during the flyby and are likely to generate valuable scientific data on the solar wind in the vicinity of Mercury.
During this flyby, BepiColombo approached Mercury from the night side, Benkhoff noted, which meant that imaging could not begin until 4 minutes after the closest approach, when the planet was sufficiently illuminated. By this time, the probe was about 800 km from Mercury’s surface.
The images, which ESA plans to release in about a day, should reveal craters and tectonic faults on Mercury’s sunburned surface.
“Even during fleeting flybys, these scientific ‘grabs’ are extremely valuable,” Benkhoff said in an ESA study. declaration (opens in new tab). “We can pilot our world-class science lab through diverse and unexplored parts of Mercury’s environment that we won’t have access to once in orbit, while also beginning preparations to ensure we transition to the main science mission. as fast and smooth as possible.”
BepiColombo is only the second probe in history built to orbit Mercury, after NASA Messenger mission, which studied the tiny rocky planet between 2011 and 2015. (Although in the 1970s, NASA sailor 10 made three flybys of Mercury while in orbit around the Sun and took the first images of the planet).
Mercury is a strange world where temperatures reach up to 800 degrees Fahrenheit (420 degrees Celsius) in parts exposed to the sun, but where, at the same time, scientists believe ice water remains in permanently shaded craters around the poles.
Mercury, though geologically dead at first glance, also shows evidence of some form of tectonic activityand boasts an amazing magnetic field that scientists so far cannot fully explain. Many of these mysteries were discovered by Messenger, and scientists are hoping that BepiColombo will provide the missing answers.
BepiColombo still has four flybys before it finally settles into orbit around Mercury. The next flyby will take place in about a year. However, next month, BepiColombo will make the closest approach to the Sun of its entire mission.
Reaching Mercury is notoriously difficult, harder than reaching the distant giant planets. Jupiter and Saturn. The reason for this is that the sun gravity constantly accelerates any probe linked to Mercury, which needs to release energy and speed – hence the long and winding journey of planetary flybys.