Why is the movie “Event Horizon” called that?

Question

In astrophysics, an event horizon is a boundary beyond which events cannot affect an observer. But what does that have to do with the movie?

Answer 1

It's the name of the spaceship they go to rescue.

The Event Horizon was built with a gravity drive, designed to generate an artificial black hole and use it to bridge two points in space, thereby reducing travel time over large distances.

To enter a black hole, one passes the event horizon.