Source: Event Horizon (1997) Movie
This is the countdown timer, which was used to tell when the ship would explode
It's actually spliced together from a few different scenes, as each one was too short on it's own
It was used both in the LCARS UI (in April Fools mode when you used an Auto-Destruct timer of 10 minutes) and the LCARS Wear apps
If a timer is running, this screen will show the time remaining instead of the current time.