In the orbit of Marsa strange and enigmatic moon travels its trajectory twice a day. It’s about Fobosthe eldest of the two Natural Satellites of the Red Planetwhose composition and origin continue to be a mystery.
Despite decades of observation and scientific theories, it has not yet been determined if it is a captured asteroidthe remains of a disintegrated comet or the result of a Cosmic impact.
The Japan Aerospace Exploration Agency (Jaxa) prepares to solve this enigma with the mission Martian Moons Exploration (Mmx), which will closely analyze the Martian moon and also bring samples to Earth for the first time in history.
The Martian moons were discovered in 1877and since then they were subject to scientific speculation. Unlike the satellites of other planets, Phobos and Deimos They present unusual characteristics that challenge conventional explanations about their origin.
Some theories suggest that they are captured asteroids of the main belt between Mars and Jupiter, due to their dark and rich surfaces in organic compounds.
However, this hypothesis conflicts with the fact that both moons have orbits almost Circulars and aligned with the Martian Ecuadorsomething rare in captured bodies.
Another possibility is that they have formed after a giant impact against Mars, similar to the one that gave rise to the Earthly moonalthough their differences in composition with the planet question this idea.
For Pascal Leefrom the SETI Institute, the mystery is still open. “They are the only objects at this stage of the solar system of which We have no idea what they are”He said to New Scientist.
Uncertainty is shared by Abigail Fraemanfrom the NASA’s jet propulsion laboratory, who considers that this is one of the biggest questions of the Planetary Science.
Fobos, the oldest of the two moons, has alone 27 kilometers in diameter at its widest point. Its orbit is extremely fast: complete a return around Mars in just 7.5 hourswhich makes it out of the west and putting on the east twice a day Martian.
But the most unusual is its destiny: phobos is slowly falling towards Mars at a pace of almost two centimeters per year. In a Term of 100 million yearsthe moon will crash against the planet or disintegrate, forming a rubble ring that could persist for millennia.
In addition, its low density suggests that it is not a solid body, but an accumulation of Porous debris with internal cavities.
This fact took extravagant speculation, such as the Soviet astrophysicist at the time Iosif shklovskiiwho came to raise in 1966 the possibility that Fobos was a Hollow artificial satelliteaccording to New Scientist. Although this idea was discarded, it is still a body with difficult characteristics to explain.
For David Mintonfrom the Purdue University, the situation is unusual: “If it is 4.5 billion years old, like everything else in the solar system, it turns out that We are observing it during the last and tiny percentage of your life”
With the purpose of answering these questions, the Jaxa will launch in 2026 The mmx mission. This spacecraft will have as its main task the detailed study of phobos and the collection of Surface sampleswhich will be brought to Earth in 2031.
The plan is that the MMX probe spends several months analyzing the moon before descending and collecting material in a barely 2.5 hours.
The examination of these fragments in land laboratories will exceed any analysis that can be done in space. The information obtained could confirm whether Fobos originated from Mars, if it is a captured object or if it comes from an even more remote region of the solar system.
According to Sonia Fornasierof the Paris Observatorythis mission could shed light on broader processes of planetary training: “That NIt will tell you something very important about the mechanisms that carry these important ingredients to the interior planets. ”
Beyond solving a planetary mystery, MMX could have an impact on the future of the human exploration.
Phobos could become A support point for manned missions To Mars. Its severity is extremely low – a thousandth part of the Earth – which would facilitate landing and takeoff maneuvers.
In addition, if the probe detects Great ice reservations insidethe possibility of extracting water and using it as fuel for rocketswhich would make phobos a key station for future interplanetary missions.
For Lee, this would completely change the panorama of Martian exploration: “If phobos and dems They are rich in volatile or waterthen there will be no bet on your human future. ”
