BepiColombo Mission Discovers New Insights During Sixth Mercury Flyby

On 8 January 2025, the BepiColombo mission, a collaborative effort between ESA and JAXA, achieved a remarkable milestone with its sixth flyby of Mercury. This flyby, crucial for calibrating the spacecraft’s trajectory into orbit around the planet, yielded astonishing images that capture the essence of this enigmatic celestial body. Let us delve into the top three images from this significant encounter, revealing new insights into Mercury’s geology and surface features.

M-CAM 1: Peering into Mercury’s Shadowy North Pole

The first striking image was captured by M-CAM 1 as BepiColombo glided a mere 295 kilometers above Mercury’s surface. This view, taken just after traversing the terminator—the dividing line between day and night—afforded researchers a rare glimpse into the shadowy depths of craters at the planet’s north pole. Notable among these craters are Prokofiev, Kandinsky, Tolkien, and Gordimer, whose rims perpetually shroud their floors in darkness, making them some of the coldest locations in the Solar System.

Exciting evidence suggests these permanently darkened craters may harbor frozen water. The quest to ascertain the presence of water within these icy enclaves is one of the key mysteries BepiColombo aims to unravel over its mission lifespan. The juxtaposition of these shadowed craters against the surrounding sunlit plains highlights a stark contrast, illustrating the complex and dynamic nature of Mercury’s surface.

M-CAM 1: The Sunlit Terrain of Borealis Planitia

In another captivating image taken shortly after the first, M-CAM 1 revealed a broad swath of Mercury’s sunlit terrain. Dominating this view is the Mendelssohn crater, whose submerged interior suggests that it has been flooded by past volcanic activity. This crater, along with many others, lies within Borealis Planitia, an extensive volcanic plain formed approximately 3.7 billion years ago through the eruption of fluid lava that reshaped existing craters.

Furthermore, the vast Caloris basin—a gargantuan impact crater spanning over 1500 kilometers—captures the imagination. The calamitous event that created this basin left a lasting imprint on Mercury’s surface, generating linear troughs radiating from the impact site. A striking feature of this image is a boomerang-shaped luminous area thought to connect to a deep trough. Understanding the direction of ancient lava flows, whether into or out of the Caloris basin, remains a tantalizing question for future analysis.

M-CAM 2: Surface Brightness and Geological Activity

The third remarkable image, obtained by M-CAM 2, showcases the intriguing relationship between surface brightness and geological youth on Mercury. In stark contrast to its darker surroundings, the bright area known as Nathair Facula stands out prominently. This location marks the site of the largest volcanic eruption on Mercury, characterized by a volcanic vent approximately 40 kilometers across. Despite the planet’s overall dark appearance, the bright patches signify youthful features that arise from recent geological activity.

Another young formation captured in this image is the Fonteyn crater, which formed merely 300 million years ago. Its brightness is indicative of its relatively recent geological formation, with fresh impact debris radiating outward, showcasing the dynamic nature of Mercury’s surface and its continual change over time. The BepiColombo mission aims to deploy various instruments to analyze the differing compositions across Mercury’s surface, shedding light on its geologic history and the processes that shaped it.

BepiColombo’s sixth flyby not only provided spectacular imagery but also left an indelible mark on our understanding of Mercury. Each image serves as a portal into the planet’s past, revealing complexities that scientists are eager to explore further. With the mission poised to separate into two orbiters by late 2026, the scientific community remains poised to unlock the remaining mysteries of this intriguing world, seeking answers about the origins and evolution of Mercury within our Solar System.