When a rocket ship gaining speed in outer space runs out of fuel it?

When a rocket ship in outer space runs out of fuel, it will continue to coast forward due to inertia, as there is no air resistance to slow it down. The ship will gradually lose speed over time due to gravitational influences from nearby celestial bodies, but it won't stop immediately. Without fuel, the rocket cannot change its trajectory or speed, making it reliant on its initial momentum. Eventually, if no external forces act upon it, it will drift indefinitely in the vacuum of space.