Apollo 11 50th Anniversary

[cdmackay]

(07-29-2019 04:41 AM)Thomas Okken Wrote:  

(07-28-2019 11:01 PM)cdmackay Wrote:  floating around in the free-fall environment [note I didn't say weightless ].

But they're the same thing. Weight is what happens when something resists the force of gravity, which in freefall by definition does not happen. Now a massless environment, that would be something else.

I was taught that weight is the force on a mass due to gravity. That force is (almost) identical whether the mass is in the ISS in orbit, or on the earth's surface. By that definition it's incorrect to say weightless, although even NASA sometimes do it, although some will say apparently weightless. I've seen interviews with astronauts who stop and correct themselves when they say it

See, for example here "On orbit, the shuttle weighs 250,000 * .907 = 226,757 pounds. Notice: the weight is not zero. The shuttle is not weightless in orbit."

I agree, it depends on your definition of weight.

Worse still are those who say "they're weightless because there's no gravity"