There are probably MILLIONS if not BILLIONS of rogue planets out there. One of them could be headed for earth. Think about this. There are hundreds of billions (200 to 400 billion) of stars out there. Each with planets. If just 0.01% of those star systems ejected just 1 planet that would mean there are 200 million to 400 million rogue planets just floating around out there in our galaxy. That’s a lot rogue planets! Any one of which could fly into our solar system at any given time. If that happens, there’s a possibility it could impact earth. If it did, it would be an extinction level event on a scale never seen in the history of our planet. All life would be wiped out. Nothing would survive. Hell, Earth itself may not survive. Some rogue planets are as big or BIGGER than Jupiter. A rogue planet that size would swallow earth whole without even blinking. A Jupiter-sized rogue planet wouldn’t even have to impact earth to destroy it. Just entering the inner solar system the gravity from a Jupiter-sized rogue planet could rip Earth apart, or push it out of it’s orbit and fling it into the sun or out of the solar system entirely. All life on earth would go extinct. Except maybe bacteria that could hibernate on the now frozen snowball earth. No one knows how long microbes can survive for sure. Millions of years? There’s also a possibility that as earth is flung from the solar system that it could graze close enough to the Sun to scorch earth on it’s way out of the system, boiling off the oceans and stripping atmosphere. This would likely destroy all life, sterilizing the planet entirely. So yeah…Rogue planets are out there, and they’re likely plentiful. They’re an invisible danger. We’re not really looking for them that much. They don’t pose an immediate danger…that we know of. There could be one out there somewhere that we haven’t discovered yet that’s on a path for our planet. It’s a terrifying thought. But whatever, we have money and sports and politics and movies and TV shows to distract us from that kinda thing.