how do you compare mass and weight on the earth, moon, and outer space?

Answer 1

Multiply mass by the local acceleration of gravity (g) to get weight. On the moon, g is 1/6 of the value on Earth.

In outer space, you have to add up the gravitational forces of all nearby large bodies and take the resultant, and divide by the mass, to get the local g. Feeling "weightless" in free fall does not mean that you have no weight. You can feel "weightless" in a falling elevator, but you still have weight.