The European Space Agency’s BepiColombo spacecraft recently made a close flyby of Mercury, and it snapped some stunning pictures along the way.
Launched in 2018 along with Japanese space agency JAXA, the spacecraft is preparing to go into orbit around Mercury in 2026, when it will perform up-close analysis of the planet’s surface, interior, and magnetic field. To get into position, the spacecraft performed two flybys of Venus, and has now performed four of six planned Mercury flybys. Each of these flybys offers the opportunity to glimpse the planet as the spacecraft passes by.
“The main aim of the flyby was to reduce BepiColombo’s speed relative to the Sun, so that the spacecraft has an orbital period around the Sun of 88 days, very close to the orbital period of Mercury,” explained Frank Budnik, BepiColombo flight dynamics manager, in a statement. “In this regard it was a huge success, and we are right where we wanted to be at this moment. But it also gave us the chance to take photos and carry out science measurements, from locations and perspectives that we will never reach once we are in orbit.”
The images were taken using BepiColombo’s three monitoring cameras, which sit on the rear of the spacecraft and take low-res black-and-white images. Because of the position of the cameras, you can see the spacecraft’s antennae in the images.
One of the special features of these images is that the spacecraft approached the planet from its nightside, or side facing away from the sun, so as the spacecraft passed by it saw the surface being gradually illuminated. The best images were taken by the second monitoring camera, including a fantastic view of the famous Vivaldi crater, seen above, which measures 130 miles across.
The goodbye image taken as the spacecraft departed Mercury is particularly striking, showing most of the planet’s face illuminated by the sun. Visible in this image is a newly named impact crater, called Stoddart after New Zealand artist Margaret Olrog Stoddart, located right at the bottom of the image near the middle.
Now BepiColombo is heading back into the solar system before aiming to arrive in orbit around Mercury in November 2026. Then the spacecraft’s main camera will be unshielded and it will take higher-resolution images, along with lots of other science data.
“BepiColombo is only the third space mission to visit Mercury, making it the least-explored planet in the inner Solar System, partly because it is so difficult to get to,” said Jack Wright of the European Space Agency. “It is a world of extremes and contradictions, so I dubbed it the ‘Problem Child of the Solar System’ in the past. The images and science data collected during the flybys offer a tantalizing prelude to BepiColombo’s orbital phase, where it will help to solve Mercury’s outstanding mysteries.”