Basic Information
The Event Horizon is the point in space (think of it as an imaginary line or sphere) where light gets caught in orbit around a Black Hole. Any matter that crosses the event horizon is stuck an unable to ever get further away from the black hole - at least not without a FTL Stardrive or a hyper drive or something of the sort. Light and information can't escape, so you can even send a MayDay Distress Call message to warn other ships in the area - at least not without a Subspace Ansible.
If you're right at the horizon and you look perpendicular to your motion, you'll see light that has circled around. If the Schwarzschild Radius is small enough (in other words, if the black hole is small enough), you may actually see yourself in the distance, or even a chain of yourselves, as light runs circuits around similar to what happens on a hypersphere. Of course, if the black hole is large, the diameter of the event horizon may be so long that you and your spacecraft are tiny specks. One dramatic element the GM could narrate would be the ship's automated proximity alarm going off, as the computer suddenly detects several other ships. This phenomena would alert you to the fact that you'd reached the Event Horizon, but it'd already be too late to escape. Unless you can travel Faster Than Light, the best you could do at this point is establish an orbit of the black hole. Again, the likely speed your craft was traveling at, and the relatively narrow band of the event horizon, means you're not likely to be in the orbital plane for long.
If the black hole is on the smaller side, the side of your Spaceship closest to the center may immediately start being distorted and crushed by the incredible gravity. In a game-universe where Gravity Sucks this may drag you straight in to the middle before you can really react.
It's also at least theoretically possible that some sort of black hole firewall exists that prevents anyone or anything from ever crossing the event horizon.
Sources
Game and Story Use
- Makes a good terrain hazard in a science fiction game - see interstellar terrain for links to more possible hazards.
- For more on the science of the event horizon see black hole.
- One interesting possibility if a large black hole is somewhere that's highly trafficked is that there could theoretically be a veritable fleet of derelict ships in orbit just inside the Event Horizon. Think of it like an outer space equivalent of the Bermuda Triangle.
- If the black hole is moving about with the velocity of a rogue star, it could have been swallowing up a long registry of missing ships from various eras and locations. Intense gravity and relativistic speed can cause all sorts of crazy time dilation, so if you don't sweat the details too closely, you might have ships that vanished hundreds of years ago still be actively crewed, and the crew may have only experienced a few weeks of the personal passage of time. Then you could have a big pirate battle, or crazy disaster movie scenario as various crews attempt to hijack the latest entry to steal their supplies.
- That might even make an interesting setting for an entire campaign. A little bleak, perhaps, especially if there's no chance of escape. Definitely memorable and unique.