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Asma Lamnawar wrote on Wednesday Feb 24, 2021 1:14 am – A study has found that the moons of Mars, Phobos and Deimos are essentially part of what was once a much larger Martian moon that was destroyed by a massive collision.
In this context, the British site “Daily Mail” published an article translated by the site “Voice of Beirut International”, declaring …
The collision between the moon and a stray rock, possibly an asteroid, is believed to have occurred between 1 and 2.7 billion years ago, triggering a powerful explosion.
Two pieces of this violent explosion remained trapped in the orbit of Mars, and they are what we now call Phobos and Deimos.
Seismic data from NASA’s InSight mission was fed into a computer simulation to determine the historical orbits of each of the current satellites.
“The idea was to follow the orbits and their changes in the past,” explains Dr Amir Khan of the University of Zurich and the Institute of Geophysics at ETH Zurich.
The data showed that Phobos and Deimos had, at one point, crossed paths, indicating that they were likely to be in the same location and therefore of the same ancestry.
ETH Zurich astronomers, writing in their study, published in Nature Astronomy, concluded that they came from a much larger celestial moon. The calculations were based on estimates of the properties of the two moons.
The two moons were discovered in 1877 by the American astronomer Asaf Hall. The moons are named after twins from Greek mythology, the children of Ares (Mars) and Aphrodite (Venus).
Phobos is the Greek god of fear and terror while Demos is the personal god of terror and terror.
Phobos is the largest, measuring 13.9 miles wide, while Demos is only 7.5 miles in diameter, and the former is closer to Mars than the smaller twin. The Earth’s moon is 2158 miles in diameter, 155 times the size of Phobos and 288 larger than Demos.
“These little moons are like potatoes because they are irregular in shape,” explains Amirhosen Bagheri, a doctoral student at the Institute of Geophysics at ETH Zurich. He adds: “Phobos and Deimos look more like asteroids than natural satellites.”
Astronomers have been puzzled by the origin of the two moons for decades, unable to explain their unusual characteristics.
Their irregular shape is unusual in space, as planets and moons become rounded over time due to gravitational forces exerted on them.
The fact of their appearance was another dilemma: they look like asteroids, but their orbits do not fit this theory.
Asteroids float in space and can sometimes get trapped in the orbit of the planet.
When this happens, they enter and reside at an angle to the planet they orbit and often have elongated eccentric orbits at one end.
However, Phobos and Deimos orbit in an almost circular fashion around Mars, parallel to the equator of the red planet.
To solve the puzzle, astronomers in Zurich compiled data on the properties of the rocks from which the moons were made that InSight obtained and combined it with measurements collected by other Mars probes.
This allowed researchers to model spatial phenomena known as tidal forces that state that each celestial body exerts a certain force on its neighbors.
For example, the Moon and the Earth are in a state of constant warfare, and so are all diads made up of a planet-moon.
But the magnitude of the tidal force depends on several factors, including the proximity, mass and composition of the objects in the equation.
For Mars, Phobos and Deimos, the first two factors are easy to calculate, but the third factor is relatively unknown because no samples were obtained from the Martian moons.
Japan hopes to reach Phobos in 2025 and take samples from its surface and send them back to Earth for analysis.
The best estimates are that moons are made of an extremely porous material with a very low density.
Measurements from InSight and other projects indicate that satellites have a density of about two grams per cubic centimeter. This means that it is lighter than chalk (2.5 g / cm ^ 3) and limestone (2.7 g / cm ^ 3).
This data was essential in enabling researchers to piece together the history of the moons and uncover their violent origins.
Historical forecasts have also been used to calculate future predictions of the fate of the moons.
He revealed that the ancestor of Phobos and Deimos was further from Mars than Phobos today and that he would likely be in an orbit similar to Demus.
Due to its proximity to Mars, Phobos is slowly approaching Mars and is likely to strike it in less than 40 million years.
As for Dius, it will have an end similar to that of the Earth’s moon as it slowly moves away from Mars, and one day it will free itself from the orbit of the Red Planet.
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