admin Collisions between moons and planets could be a permanent danger to the possibility of extraterrestrial life
Moon crashing into Earth could look like an unrealistic doomsday scenario or sci-fi catastrophe. But for some planets in other star systems, such catastrophic collisions may be common.
New research published in the journal Monthly Notices of the Royal Astronomical Society uses computer simulations to show that collisions between exoplanets and their moons (called exoplanets) ) could in fact happen frequently, which could spell disaster for any budding extraterrestrial life on these planets.
While astronomers have yet to reliably detect an exomoon, scientists expect them to be abundant in the universe.
“We know a lot of moons in our solar system, so naturally they are,” said Jonathan Brande, a University of Kansas astrophysicist who was not involved in the new study. I expect to see moons in exoplanet systems. An email. . Therefore, theorists such as Brad Hansen, an astronomer at the University of California, Los Angeles and author of the new study, are interested in discovering how moons and exoplanets might interact with each other. each other and how those interactions affect the possibility of life in distant stars. systems.
Runaway moons
Gravity governs the interaction between a planet and its moons, manifesting itself in tides and other effects, such as the receding of our moon. Each year, Earth’s moon moves more than an inch away from our planet, its orbit getting bigger and bigger each year. At the same time, the Earth rotates a little slower each year. These two effects are directly linked:
The Earth transfers part of the angular momentum of its rotation to the Moon’s orbit.
If this compromise lasts long enough, the moon could eventually separate from Earth. Luckily for us, this process will take so long that the sun will explode long before the moon can fully escape. But around some exoplanets, especially those that are closer to their stars than Earth is to the Sun, the situation can develop much more rapidly, with planets and moons “not stable” collided during the first billion years of their formation, according to Hansen’s calculations. (For comparison, the Earth and its moon are about 4.5 billion years old.)
In his simulations, moons drifting away from their host planets often return with a bang, crashing into the planet and creating giant dust clouds. These dust clouds glow in the infrared, when they are illuminated and warmed by the light of the stars. But they only last about 10,000 years before disappearing – a cosmic blink.
Observations from NASA’s Wide Field Infrared Survey space telescope show that every star will experience such an event at some point in its life, Hansen said. It makes sense, he added, that these dust emissions represent collisions between the planets and their moons.
Because these dust clouds are short-lived, astronomers have only observed about a dozen clouds. Furthermore, some astronomers still do not believe that these dust clouds come from exomoons, suggesting instead that they may be the result of collisions between the two planets. Either way, more observations are needed to understand the role of exoplanets in the evolution of an exoplanet and to determine if these collisions could affect extraterrestrial life. Are not. “The moon is generally considered useful,” says Hansen. They are thought to help stabilize the tilt of the planet’s axis, making the seasons milder and more favorable for life. However, a collision like the one in Hansen’s simulations would certainly overwhelm this advantage by destroying any chance of life in a violent explosion.
Observations from NASA’s Wide Field Infrared Survey space telescope show that every star will experience such an event at some point in its life, Hansen said. It makes sense, he added, that these dust emissions represent collisions between the planets and their moons.
Because these dust clouds are short-lived, astronomers have only observed about a dozen clouds. Furthermore, some astronomers still do not believe these dust clouds come from exomoons, suggesting instead that they may be the result of a collision between the two planets. Either way, more observations are needed to understand the role of exoplanets in the evolution of an exoplanet and to determine if these collisions could affect extraterrestrial life. or not. Are not. “The moon is generally considered useful,” says Hansen. They are thought to help stabilize the tilt of the planet’s axis, make the seasons more temperate and more supportive of life. However, a collision like the one in Hansen’s simulations would certainly nullify this advantage by destroying any chance of survival in a violent explosion.
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