It’s a bit much to lump in New Scientist with the lay press, but it’s certainly no peer-reviewed journal. I call MIT Technology Review the same. In the 8 Feb 2025 issue (vol. 265, No. 3529):
Drake, Nadia Destination Phobos p. 34
Mars’ natural satellites are, apart from existence and basic physical stats, poorly known. Almost all our current knowledge happened to come from Mars probes which diverted their observing program from ‘down’ to ‘sideways’, which Drake acknowledges. All this will change with (including years after) the Japanese MMX mission, a major (but not the only) theme of Drake’s piece.
One hypothesis for the origin(s?) of Phobos and Deimos is a giant impact- a collision of Mars and some mega-impactor sprayed material into the Martian sky, some of which survives as the two satellites. However, neither of the two looks like Martian rock, while Earth’s natural satellite appears Earthlike down to an eerie decimal place. This might imply the capture hypothesis, where Phobos and Deimos were just orbiting along when Mars’ gravity trapped them. But we would expect them to have irregular orbits; instead, their orbits are equatorial and circular- eerily regular.
The two look, as far as we can see, like D-type asteroids or similar. These are found in the outer Main Belt and outer Solar System. This typing would imply richness in organics and volatiles, potentially water ice. Drake quotes one scientist’s musings- could the two be giant impact products, yet somehow mostly impactor material, not Mars rock? We’re getting that desperate for answers. Impact by D-, P-, or similar-type small bodies could explain the presence of water on Mars and Earth. And should one or both satellites be rich in organics, water, and other volatiles, they would make inherent bases for future missions.
The MMX mission (Mars Moons eXploration) will make flybys of Deimos, close maneuvers about Phobos, and then finally land on the large, inner satellite. MMX will blow in several grams of Phobos’ surface, using a collector based on OSIRIS-REx’s sampler. The mission will also attempt to take a core sample, preserving depth information; one possibility is that the outermost, visible surfaces are space-weathered, and not representative of the bulk Phobos. Even with grams of sample, we can study Phobos in excruciating detail. Another, exciting possibility is that Phobos’ gravity has collected bits of Mars, thrown into space by subsequent large impacts. Given a large enough sample, odds are good that a small fraction of particles in it are actually Martian.
MMX is scheduled to launch next year, then return its precious sample in 2031. Can’t wait!