Scientists have found that if a star passing through our solar system might move Neptune’s orbit by just 0.1%, it would cause chaos, smashing into other planets or kicking them out of the system entirely.
A slight shift in the outer planet’s orbit might eventually cause other planets to collide with each other or be driven out of the solar system entirely, RT reports.
According to a research paper published in the Monthly Notices of the Royal Astronomical Society, a very neighboring star approaching our solar system might cause such a chaotic event.
Simulations by scientists Garrett Brown and Hanno Ren at the University of Toronto suggest that a star flying next to it would only need to push Neptune’s position three times the distance between Earth and the Sun to make the planets out of control.
Brown and Wren ran 2,880 simulations with 960 of them with varying degrees of perturbation from a possible stellar flyby, studying the followingeffects up to 4.8 billion years later. In only four of those scenarios did Mercury hit Venus.
One of the possible starting points for the instability of the solar system was the smallest planet, Mercury.
Mercury’s perihelion (the closest point in a planet’s orbit around the Sun) moves regarding 1.5 degrees every 1,000 years, a rate very close to Jupiter.
And if the two happen to synchronize, resonate—there is a 1% chance that Mercury will be pulled out of orbit, ejected from the Solar System, or launched into a collision course with Venus, the Sun, or even Earth over the course of the next three to four billion years.
While Mercury is too close to the sun to feel the effects of a passing star, Neptune will, and the turbulence will cause the solar system to ripple.
And the effects of a shift of 0.1%, which is equivalent to 4.5 million km in the semi-major axis of Neptune, might extend to Earth and Mars in just 20 million years.
In other models in the simulation, there are 1920 models, 26 of them ended up breaking into the planets each other or expelling Uranus, Neptune or Mercury completely.
But don’t panic so far as the team estimated that the chance of a star getting close enough to make this happen was tiny — only regarding once every 100 billion years or so, with an impact taking millions of years.