The two small moons of the Red Planet – Phobos and Deimos – could be formed after an ancient catastrophe, according to a new study. It’s an interesting possibility, but not everyone is convinced by the evidence.
Phobos and Deimos are similar to potatoes (although this may be seen as a misnomer on potatoes). The origin of these unruly branches is not entirely clear, but their strange shape, coupled with their reduced size, has led to the probation that they are captured by asteroids. Of course, Phobos measures 14 miles (23 kilometers) wide and Deimos 7 miles (11 kilometers) wide, so this is not an entirely rural idea.
Other factors, however, must be considered, such as their unusual shapes (they are very different from Mars from a geological point of view) and their unexpected orbit. Of course, captured asteroids should have long orbits and random inclination angles, none of which belong to Phobos or Deimos. Instead, the two moons that orbit the Red Planet orbit are very spherical orbits.
Another possibility is that the two moons are the remains of an ancient catastrophe, a hypothesis considered by Amirhossein Bagheri, a doctoral student at ETH Zurich and lead author of the new Astronomy of Nature paper on the subject.
Bagheri and his colleagues ran computer simulations of the two moons, but instead of running their models forward from a set of expected scenarios, the scientists ran them back to monitor movements. historical status of the hills over time. The symbols certainly showed that Phobos and Deimos were in fact crossing paths.
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This means that “the branches were very similar in the same place and therefore had the same origin,” study co-author Amir Khan, a senior scientist at the University of Zurich and ETH Zurich, explained in a recitation. By “same origin” Khan refers to a single parent object – a larger Martian moon that no longer exists – that was separated after being hit by a square object, such as an asteroid or comet. Bagheri said that Phobos and Deimos are “the remnants of this lost moon,” which they argue was in an orbit that was nearly synchronous (i.e. an orbital time that corresponds to the planet’s orbit) around Mars .
To run these symbols, however, the team had to find out how Mars and the two moons interacted over the birds, bringing in the tidal forces of the tide. play and the resulting energy distribution.
Thanks to NASA ‘s InSight probe, and its ability to monitor seismic activity on Mars, scientists have a better understanding of what’ s happening beneath the Martian surface. The same cannot be said, however, for the Martian branches, but scientists take pictures and measurements collected by remote sensing. Phobos and Deimos are like Swiss cheese, full of caves, and can contain water ice in part.
Equipped with their updated variables, the scientists ran the models, showing that the birth of the two moons occurred at some point between 1 billion and 2.7 billion years ago. The rather large difference is due to uncertainty about the complexity of the two moons. Better data could clear this up, and the good news is that the Japanese space agency is planning a mission to Phobos, known as Martian Moons Study, in which a probe returns surface samples at some point later in this decade.
While the study provides an interesting insight into the history of the moons, Matija Ćuk, a research scientist at the SETI Institute, was not convinced by the findings.
“The authors have a detailed model for a tidal wave in Mars, but they are really stretching the physics when it comes to tides within the mountains,” he said in a post- d. “More importantly, their position makes no sense because they are processing the phobias of Phobos and Deimos to cross billions of years ago at [a very] relatively high speed – much more than expected with a unified body break. “
Ćuk said the idea of a single Martian moon in an orbit that is nearly synchronous about 2 billion to 3 billion years ago is “probably unbelievable,” since the moon would move to from such a situation, and ultimately “that does not help to solve any of the questions that people have about the situation.rigin of Phobos and Deimos, ”he said.
He added: “I am amazed that this paper has been approved in a prestigious journal such as Nature Astronomy. ”
Ćuk, along with his colleague David Minton of Purdue University, have their own ideas about Phobos and Deimos. In research published last year, the scientists further confirmed that Phobos is trapped in a cycle of death and rebirth that rings from around the Red Planet from time to time and temporarily. Eventually these rings spawn new branches, which is another explanation for how Mars got its branches.