Cosmic threats are always with us.

"Rogue planets may be numerous in the galaxy, but it surprises most to learn that there are between 100 and 100,000 rogue planets for every star in our galaxy, putting the total number of planets wandering through the Milky Way at somewhere around a quadrillion" (BigThink, Most planets in the Universe are orphans without parent stars)

The planetary defense is a thing. That we should think. The universe including our solar system is full of asteroids and dwarf planets. Some of them are small and we can see them at the last minute. And some of them are seen when they travel past the Earth. But the fact is that. Larger asteroids can cause larger threats than small asteroids. 

If about a 100-meter-size asteroid hits Earth. That will cause very large destruction. It's quite easy to defend cities and Earth against small asteroids. But if the problem is that if some Ceres-size asteroid comes to Earth we see that thing far away. 

And that means we have time to destroy that target. If there is lots of water on the asteroid the large-size nuclear weapon can detonate a hole in the ice that can cover the ocean. And then that erupting water acts like a rocket engine. That pushes the large asteroids away from their trajectories. 

But if a large asteroid like Ceres hits our planet that is the end of life here. In some horrifying scenarios, the large asteroid impacts the moon and then pushes it to impact the course of the Earth. Cosmic catastrophes can wipe any civilization into history and transform any planet into a cosmic molecular cloud. 

One of the threats is the rogue planets. Rogue planets can come into our solar system just like some asteroids. And a big rogue planet can turn the solar system into chaos. 

Most of the planets in the universe might be without parent stars. People call those planets as rogue planets. The rogue planet travels all around the universe. Some of them might be the result of a supernova or nova eruption. But it's possible. The planet can form spontaneously far away from stars, and that means. Rogue planets can be more common than we thought. 

The traveling planets are always a risk to solar systems. If a large, about Saturn-size rogue planet arrives in the solar system, that causes chaos. Those massive rogue planets will pull the asteroids and moons from their trajectory. But smaller rogue planets can also pull things like asteroids from the Kuiper belt behind them. 

The thing is that the threat of rogue planets is real. And if we face a situation where a rogue planet arrives in our solar system. We would need a very powerful tool. That can turn that planet away or crush it. The antimatter bomb can destroy a large planet. And then the laser systems can destroy those asteroids that will travel to our solar system. Or we can just sit and wait for the impact. 

The choice is that we will stand without making a thing. That can mean that the large object can impact Earth. If Earth impacts with a Mars-size planet that will be the end of our world. The thing is that the small rogue planets might be planets that the star explosion pushed away. And large rogue planets can be planets that formed outside the star's gravity field. 

https://bigthink.com/starts-with-a-bang/most-planets-are-orphans/