BepiColombo has just imaged Mercury in a whole new light—mid-infrared light, to be precise.
when the spacecraft made its fifth flyby mercury Earlier this month (six planned flybys), BepiColombo pointed its Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS) at a region of Mercury’s northern hemisphere. Mid-infrared light is invisible to the human eye, but it carries a wealth of information about the mineral composition and temperatures of very hot rocks, such as those on Mercury’s sun-baked surface. The December 1 flyby marked the first time Scientists have observed Mercury’s surface in mid-infrared wavelengths, and the new view reveals some tantalizing clues about Mercury’s geology.
Bepi Colombo Passes Mercury at a distance of 37,626 kilometers December 1 (approximately 23,400 miles). It happened on September 4thas the spacecraft passed just 165 kilometers (103 miles) above Mercury’s battered, charred surface. When BepiColombo enters orbit around Mercury in late 2026, it will pass within 590 kilometers (370 miles) of its closest point to Mercury before returning to 11,640 kilometers (7,230 miles). But to get there, the spacecraft takes a spiral route through the interior. solar systemusing the force of gravity Earth (once), Venus (twice) and Mercury (six times), taking it on the right path at the right speed and ultimately into orbit around Mercury.
These six flybys of Mercury, the last of which will take place in January 2025, provide researchers with the opportunity to test the spacecraft’s instruments and collect scientific data that will help them refine BepiColombo’s plans for scientific research in orbit. One of the big questions about Mercury that scientists hope to answer in the coming years is what its surface is actually made of — and what that tells us about how the planet formed so dangerously close to the heat and energy of the sun and evolutionary. gravity. They hope the MERTIS instrument will shed new (mid-infrared) light on the question, because most rock-forming minerals tend to emit bright radiation in mid-infrared wavelengths when they are very hot.
Over the past two decades, MERTIS’s science team has heated minerals and mineral combinations in the laboratory to more than 400 degrees Celsius (752 degrees Fahrenheit) and then measured the mid-infrared radiation they emit. The result is a library of luminescent fingerprints of multiple minerals, which the science team can compare with MERTIS data to determine the composition of different regions of Mercury’s surface, their temperatures, and the roughness of the terrain.
“Because Mercury’s surface is surprisingly iron-poor, we have been testing iron-deficient natural and synthetic mineral. in a statement. “The materials tested included rock-forming minerals to simulate the composition of Mercury’s surface.”
The most recent flyby, MERTIS’s first chance to shine, captured a large area of Mercury’s northern hemisphere, including part of the vast volcanic plains and part of the Caloris Basin: a rocky plain within a large impact crater that, in all other orbits, It all passes directly below sun Mercury is the closest to our star. The images also include stunning views of Bashō Crater, an impact crater previously photographed by the Mariner 10 (1974-1975) and MESSENGER (2011-2015) spacecraft.
“The moment we first looked at the MERTIS flyby data and immediately distinguished the impact crater was amazing!” said Adley. “There is a lot to discover in this data set—surface features that have never been observed in this way before are waiting for us.”
From more than 37,600 kilometers (23,363 miles) away, MERTIS is able to image Mercury’s surface at a relatively low resolution of 26 kilometers to 30 kilometers (16 miles to 19 miles), enough to give the science team a broad overview, but not More detailed information about the geological history of Earth’s rocks. Once BepiColombo is finally in orbit, MERTIS will map the entire surface at a resolution of 500 meters (547 yards).