How does a rocket slow down in space?

I’ve been reading about the conservation of momentum and its applications in deriving the rocket equation. I’m curious whether how can a rocket slow down in space. As far as i can comprehend, a rocket’s change in velocity is proportional to the negative of the exhaust velocity relative to the rocket and the ratio of the natural logarithm of its instantaneous mass over its original mass (before expelling fuel). It can propel itself forward yes (increasing speed), but how can it decrease speed? The only way i can see it is by having the logarithmic ratio of the said masses to be negative (that is increasing instantaneous mass) which sounds really illogical since it implies gaining mass. Another way is by reversing the direction of its exhaust velocity. Is this how a rocket can slow down without the aid of air resistance?

• Re, "...reversing the direction of its exhaust velocity..." which can be most easily accomplished by simply turning the whole vehicle to face in the opposite direction. May 27, 2020 at 13:34