Why do my world-space particles drift behind a moving parent?

With Simulation Space = World, particles spawn at parent position then ignore parent motion. If you want them to inherit some forward momentum (rocket exhaust trailing), set Inherit Velocity to a value 0..1.

World vs Local Simulation Space?

World: particles drift independently after spawn. Use for trails, rain, snow. Local: particles move with the parent. Use for shields, auras, attached effects.

What about Custom Simulation Space?

Pick a transform other than the system's parent. Useful for parented-to-character but particles inherit velocity from a different reference (e.g. world space but with terrain wind direction).

Fix: Unity Particle World Velocity Wrong When Parent Moves

Quick answer: Set Simulation Space = World, Inherit Velocity = 1.0 for a rocket-exhaust style trail. Local for attached effects. Custom for off-axis reference.

Rocket flies forward; exhaust particles spawn at the rocket then sit still. Or particles teleport with the parent instead of trailing. Simulation Space + Inherit Velocity choose which.

The Symptom

Particle behavior doesn’t match expectation under parent motion. World drifts; Local moves with parent. Mismatch is usually inheritance settings.

The Fix

Particle System → Main module:
  Simulation Space:   World          // drift after spawn
  Inherit Velocity:   1.0            // rocket trail

  or

  Simulation Space:   Local          // move with parent
  Inherit Velocity:   irrelevant

Decision Matrix

Rocket exhaust trail: World + Inherit 1.0.
Magic aura around player: Local.
Snow falling: World, Inherit 0.
Smoke from chimney: World, Inherit 0.
Shield bubble particles: Local.

Verifying

Move the parent during play. Watch particle behavior. Adjust Inherit Velocity until trail looks right.

“Pick the simulation space. Tune inherit. Particles match motion.”

Related Issues

For sub-emitter inheritance, see sub-emitter. For trigger callback, see trigger callback.

Pick space. Set inherit. Trail follows.