Our solar system is a perfectly balanced cosmic entity that supports our Sun eight planets and one dwarf planet, Pluto. However, this gravitationally stable system has been able to stay that way because different planets play an important role in keeping it that way. For example, Jupiter, the largest planet protects the inner ring from asteroids and meteors, and Mercury rotates at such a high speed that it constantly defies the Sun’s gravitational pull to keep it in its orbit. But the planet that can affect the solar system the most is the most distant planet, Neptune. And it is not because its gravitational pull affects the other planets, but because it is the most vulnerable planet in this system.
A passing star can seal Neptune’s fate
Now, if Neptune suddenly disappeared from our solar system, not much would have changed. Pluto would probably experience a changed orbit, and Uranus might shift its orbit a bit closer to Saturn, but the rest of the planets are too far away to even notice the disappearance. Even on Earth, probably the only people who would notice this would be NASA astronomers and other scientists studying it, since Neptune is the only planet not visible to the naked eye. However, if circumstances were a little different, Neptune’s disappearance could throw the entire solar system into chaos. The solar system is not an isolated structure. It is part of the Milky Way galaxy which is full of stars, planets, black holes, asteroids, meteors, gas and dust. And all of this is in constant motion. So, in a hypothetical situation, if our solar system encountered another star, Neptune would be the first to know. According to a New Scientist report, if the star were to pull Neptune out of its orbit, the snowball effect could cause major instability in our solar system. Neptune may be the first to shift, but given how strong a star’s gravitational pull is, its effect will be felt all the way to the Sun’s core. And when each planet moves and changes its orbit, the stability of the entire solar system is destroyed. What makes it really scary are two considerations. First, the transiting star doesn’t have to be as big as the Sun to cause this chaos. And second, we might not even be able to see it coming, since the star wouldn’t need to get very close to the solar system.
