Due to the chaotic evolution of the planetary orbits in the Solar System, a close approach or even a collision could occur between Mars and the Earth in less than 5 billion years, although the odds are small.
Credit: J Vidal-Madjar, NASA, IMCCE-CNRS
PARIS: A force known as orbital chaos may cause our Solar System to go haywire, leading to possible collision between Earth and Venus or Mars, says a study.
The good news is that the likelihood of such a smash-up is small, around one-in-2,500. And even if the planets did careen into one another, it would not happen before another 3.5 billion years.
Indeed, there is a 99 per cent chance that the Sun's posse of planets will continue to circle in an orderly pattern throughout the expected life span of our life-giving star, another five billion years, the study found.
When worlds collide
After that, the Sun will likely expand into a red giant, engulfing Earth and its other inner planets – Mercury, Venus and Mars – in the process.
Astronomers have long been able to calculate the movement of planets with great accuracy hundreds, even thousands of years in advance. This is how eclipses have been predicted.
But peering further into the future of celestial mechanics with exactitude is still beyond our reach, said Jacques Laskar, a researcher at the Paris Observatory in France and lead author of the study.
"The most precise long-term solutions for the orbital motion of the Solar System are not valid over more than a few tens of millions of years," he said in an interview.
Powerful predictions
Using powerful computers, Laskar and colleague Mickael Gastineau generated numerical simulations of orbital instability over the next five billion years.
Unlike previous models, they took into account Albert Einstein's theory of general relativity. Over a short time span, this made little difference, but over the long haul it resulted in dramatically different orbital paths.
The researchers looked at 2,501 possible scenarios, 25 of which ended with a severely disrupted Solar System.
"There is one scenario in which Mars passes very close to Earth," 794 km to be exact, said Laskar. "When you come that close, it is almost the same as a collision because the planets gets torn apart."
Life on Earth, if any still existed, would almost certainly cease to exist.
sad
I can't believe the first comment; why read a science magazine if you are so brain washed you can't learn anymore, or more likely, are scared of knowledge that makes you feel frightened and you have no control over anything...
Surely, when the sun expands
Surely, when the sun expands into a red giant in 3.5 billion years time, rather than engulfing the Earth and all the other inner planets, the changes in the Suns' size would alter the Earths' trajectory and push us and the other planets away from it? I thought the orbit of each planet in the solar system was governed by a number of factors, including the Suns size and gravitational pull, so surely we wouldn't remain in the same orbit while the Sun gradually engulfs us? I need to know the answer so that I can prepare accordingly ... hehehehe!
Prepare for something 3
Prepare for something 3 billion years ahead? Btw the Sun's gonna explode anyway so it's either we get blasted off and frozen, or be engulfed by the flames of the supernova and vaporise. But either way, after 3 billion years we'll probably be out in space, in a gigantic metal structure capable of supporting every single life that used to be on Earth, with "farms" and whatsoever built into it. Maybe a man-made earth with a molten core and an artificial Sun adjusted to suit the distance. Who knows, there might even be a propulsion to move the structure around the universe.