Mysterious Mercury: BepiColombo Probe Reveals Stunning Images from Closest Ever Flyby
The European Space Agency’s (ESA) and JAXA‘s BepiColombo probe has snapped breathtaking details of Mercury’s north pole in its closest ever flyby of the innermost planet in our solar system. The robotic explorer, operated by ESA and JAXA, swooped within 183 miles (295 kilometers) of Mercury’s surface on January 8, capturing striking images that reveal a plethora of secrets about this enigmatic planet.
The probe’s cameras caught glimpses of Mercury’s dark craters, vast volcanic landscapes, and the planet’s largest impact crater, which spans over 930 miles (1500 kilometers). The recently released images showcase Mercury’s north polar region in unprecedented detail, setting the stage for the two orbiters – one European and one Japanese – to begin their detailed studies around the planet’s poles by the end of 2026.
One of BepiColombo’s cameras, M-CAM 1, captured a long-exposure image of Mercury’s north pole at 07:07 CET, when the spacecraft was around 488 miles (787 kilometers) from the planet’s surface. The closest approach occurred on the planet’s night side at 06:59 CET, with the terminator – the boundary between day and night – slicing Mercury in half. Along the terminator, precisely to the left of the solar panel, the bright rims of Prokofiev, Kandinsky, Tolkien, and Gordimer craters, along with several central peaks, can be seen. Due to Mercury’s near-vertical rotation axis, these crater rims cast permanent shadows, creating some of the coldest spots in the solar system, despite Mercury’s proximity to the Sun. Intriguingly, there’s evidence suggesting these dark craters may harbor frozen water. Determining if water truly exists on Mercury is one of the primary mysteries BepiColombo will investigate once it enters orbit around the planet.
Another image shows vast regions of Mercury’s surface blanketed in lava, with the 290-mile (466-kilometer) wide Mendelssohn crater largely filled with fine material similar to its surroundings. Smaller, younger impact craters pockmark the smooth, layered floor inside Mendelssohn. The surrounding Borealis Planitia, formed by widespread, vast lava flows around 3.7 billion years ago, has a similar scale to Earth’s largest volcanic eruptions, such as the Permian-Triassic extinction event 252 million years ago. Borealis Planitia is encircled by older terrain, featuring more craters.
"BepiColombo’s main mission may only begin in two years, but its sixth flyby of Mercury has already provided invaluable new insights about this poorly explored planet," commented Geraint Jones, BepiColombo Project Scientist at ESA. "In the coming weeks, the BepiColombo team will work hard to extract as much information as possible from this flyby data to unravel Mercury’s mysteries."
A bright feature near the planet’s top in the image is Nathair Facula, the largest volcanic complex on Mercury. At its center lies a 25-mile (40-kilometer) wide volcanic hole that has witnessed at least three major eruptions. This facility’s intricate deposits span at least 190 miles (300 kilometers) in diameter. Nathair Facula is a prime target for BepiColombo’s instruments, which will analyze the erupted material to reveal Mercury’s composition and formation history. Additionally, the relatively young Fonteyn crater – estimated to be just 300 million years old – and the 124-mile (200-kilometer) wide Rustaveli crater, characterized by its central peak ring, can be seen in the image.
These stunning images tease the scientific riches Mercury holds and the tantalizing discoveries still to be made by BepiColombo in its upcoming orbit around the planet.
