Dave Shrader wrote:
"If that assertion (I am 240 pounds "mass" on earth. That`s a fact. I am
240 pounds "mass" on moon. That`s a weird assertion!) is true, who
changed te density of the moon??"

Mass is the bulk of matter though not necessarily equal to its weight. A
mass weighing 240 pounds on earth weighs less on the moon because there
is less mutual attraction between the moon, of much smaller mass than
the earth`s mass, and the object which weighs 240 pounds on the earth.

Mass is the property which provides a body with inertia. Mass is the
mechanical analogy of inductance. Mass is equal to the weight of a body
divided by the acceleration due from gravity (32ft./sec./sec.). This is
an expression of Newton`s 2nd law of motion: F = MA, thus M = F/A.

Newton`s 1st law says that to move a body at rest, enough force must be
applied to overcome its inertia.

Newton`s 3rd law says that for every action there is an equal and
opposite reaction.

The gravitational force of the earth is stated as "1". The gravitational
force on the moon is about 0.16 that on earth, so an object weighing 240
pounds on earth would weigh only 38.4 pounds on the moon.

Best regards, Richard Harrison, KB5WZI