The BepiColombo spacecraft has sent back some incredibly detailed images of Mercury’s north pole. The snapshots were collected during its closest ever flyby of our solar system’s smallest planet. You can check out the awe-inspiring images below.
On January 8, the robotic explorer operated by the European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA) came as close as 183 miles above Mercury. The newly released images show permanently dark craters spotting the surface of the planet closest to our Sun. Nearby volcanic plains and the largest impact cater on Mercury–over 930 miles wide–are also visible.
The spacecraft launched in 2018 and has completed five previous flybys. This most recent approach puts BepiColombo on a course to enter orbit around Mercury in late 2026. It holds one orbiter for Europe and one for Japan that will circle the planet’s northern and southern poles.
M-CAM 1 took this long-exposure photograph of Mercury’s north pole at 07:07 CET, when the spacecraft was about 787 km from the planet’s surface. The spacecraft’s closest approach of 295 km took place on the planet’s night side at 06:59 CET. In this view, Mercury’s terminator, the boundary between day and night, divides the planet in two. Along the terminator, just to the left of the solar array, the sunlit rims of craters Prokofiev, Kandinsky, Tolkien and Gordimer can be seen, including some of their central peaks. Because Mercury’s spin axis is almost exactly perpendicular to the planet’s movement around the Sun, the rims of these craters cast permanent shadows on their floors. This makes these unlit craters some of the coldest places in the Solar System, despite Mercury being the closest planet to the Sun! Excitingly, there is already evidence that these dark craters contain frozen water. Whether there is really water on Mercury is one of the key mysteries that BepiColombo will investigate once it’s in orbit around the planet. CREDIT: ESA/BepiColombo/MTM.
The image shows that large regions of Mercury’s heavily cratered surface are smoothed over by lava from volcanic eruptions. This smoothing over is visible inside the 290 km-wide crater at the right of the image, called Mendelssohn. While its outer rim is still visible, it has been largely filled by the same smooth material that makes up the surrounding plains. Smaller, more recent impact craters dot the otherwise smooth crater. The vast plains surrounding Mendelssohn, called Borealis Planitia, were formed by the widespread eruption of runny lava some 3.7 billion years ago. The volume of lava making up Borealis Planitia is similar in scale to mass extinction-level volcanic events recorded in Earth’s history, notably the mass extinction event at the end of the Permian period 252 million years ago. Borealis Planitia is bordered by older and hence more heavily cratered terrain. CREDIT: ESA/BepiColombo/MTM.
“BepiColombo’s main mission phase may only start two years from now, but all six of its flybys of Mercury have given us invaluable new information about the little-explored planet,” Geraint Jones, BepiColombo’s Project Scientist at ESA, said in a statement. “In the next few weeks, the BepiColombo team will work hard to unravel as many of Mercury’s mysteries with the data from this flyby as we can.”
The bright patch near the planet’s upper edge in this image is the Nathair Facula, the aftermath of the largest volcanic explosion on Mercury. At its centre is a volcanic vent of around 40 km across that has been the site of at least three major eruptions. The explosive volcanic deposit is at least 300 km in diameter. Nathair Facula is a major target for several BepiColombo instruments, which will measure the composition of the erupted material. This will teach us about what Mercury is made of, and how the planet formed. Also visible is the relatively young Fonteyn crater, which formed a ‘mere’ 300 million years ago. Its youth is apparent from the brightness of the impact debris that radiates out from it. Older material on Mercury’s surface has become much darker from weathering as it aged. Rustaveli, seen roughly in the centre of Mercury in this image, is about 200 km in diameter. Within its rim is a ring of peaks, making it a so-called peak ring basin. These peaks barely poke above smooth material on Rustaveli’s floor, which suggests the crater has been flooded by lava. CREDIT: ESA/BepiColombo/MTM.
