Rogue star could 'kick' Earth into deep space

A team of astronomers has run more than 2,000 simulations using NASA's Horizons System tool and warns that the passage of a rogue star or group of stars could upset the way the Solar System is currently set up. Although most passages are relatively harmless, there are fears that one of these occurrences could cause chaos and end up 'pushing' the Earth away from the Sun and into deep space.

The analysis published in Icarus suggests that the disastrous consequences may be due primarily to one planet, Mercury, which is the closest to the Sun and most vulnerable to instability, as its orbit could become more elliptical. Astronomers believe that increasing the eccentricity could destabilize Mercury's orbit, causing it to collide with Venus or even the Sun, a situation that would only be made worse by the passage of a nearby star, Gizmodo reports.

The study used data from the Solar System Dynamics Group, which precisely monitors the position of objects in the Solar System. The team outlined several scenarios involving passing stars and concluded that stellar strikes over the next five billion years would increase the instability of the system by 50 percent. As for planets, Mercury and Mars are the most likely to be lost after a pass, and although the instability rate on Earth is low, there is a higher probability of a collision with another planet causing them to fall out of orbit.

“The nature of stellar-generated instabilities is more violent than internally generated instabilities. The loss of multiple planets in stellar-generated instabilities is common and happens about 50% of the time [in the simulations], whereas it appears to be quite rare for internally generated instabilities,” the team says in the study.