Sure it does. Let me build up from basic blocks here:[ul][li]Mass(m) is a scalar.[*]Velocity(v) is a vector.[/li]Thus, linear momentum (p = m * v) is a vector.[li]For purposes of calculating Angular Momentum(L) we need to define the center of rotation. This is a completely arbitrary definition, so we could choose Omaha Nebraska, but we’re going to choose the center of the pinwheel to simplify calculations. Let us then define a radius vector from the center of rotation to the object whose L we wish to calculate and call it r.[/li][li]L is r X p, a vector cross product. This has the property that when r & p are paralell, r X p is zero. When r & p are perpendicular, the magnitude of r X p is equal to |r|*|p|. The exact value of a cross product is a vector of magnitude |r|*|p|*sin <font face=“symbol”>q</font>, where <font face=“symbol”>q</font> is the angle between them. The direction of the resultant vector is perpendicular to both r and p, and the direction is set by convention to be defined by your right hand (point fingers in direction of r, curl fingers to point in direction of p, and stick your thumb straight out.)[/ul][/li]

Now that we have that, any object moving with respect to a point in space has L with respect to that point. Imagine a traffic light stuck in the middle of a road, and a car approaching it at a steady speed. Define r to be the vector from the traffic light to the car. At large distances, p is nearly parallel to r (r X p small compared to r & p). At small distances, |r| is very small and that exactly makes up for the fact that r is nearly perpendicular to p. If you do the math you’ll find that in the absence of external forces (friction, engine power, etc.) L is constant.

Back to the rocket pinwheel. Take a rocket at the edge of the pinwheel, assume a vacuum. The exhaust nozzle of the rocket is pointed perpendicular to r. Imagine a chunk of rocket exhaust that is ejected and now travels away from the pinwheel. Since its r vector grows larger, the fact that it is moving linearly is OK - it is carrying angular momentum and balances out the angular momentum that the rocket has acheived by accelerating itself around the pinwheel.

Did that help at all or am I just confusing people?