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The Last Man on the Moon


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7 hours ago, Scotty CTA said:

I'm still playing catch-up with this thread, but in the meantime I'd like your thoughts.

The trick here is to disprove the 'proofs' without going "I know that's not true because that wasn't what I was indoctrinated with."

 

They're not proofs. They're assertions. 

First one - show me the maths of what degree of curvature you'd expect to see given the scales involved. Then a direct comparison to the sensitivity and resolving power of the human eye. Then perform a comparison to prove that we should be able to see the curvature. 

Second one - again show me the maths of the situation and the given changes in radial angle that would be expected with the distances involved, versus the sensitivity of the human eye

Third one - The movement of ocean currents is exactly the effect the narrator is asking for, evidence of a large water mass moving in a rotational manner. If you can show me the force and pressure equations that say it should move in another way, that would be proof.

Not going to do any more until the first three are actually turned into proofs, rather than assertions.

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On ‎2‎/‎15‎/‎2017 at 5:16 AM, Toepoke said:

The "vomit comet" used to train astronauts for zero G.

Not really feasible for faking lengthy films of spaceflight though...

 

Hey - check this out:

 

And, since it's OK GO - another classic apropos of nowt:

 

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On 3 March 2017 at 4:43 AM, DonnyTJS said:

Hey - check this out:

 

And, since it's OK GO - another classic apropos of nowt:

 

If you know what you're looking for, what you can see in that video is spells of zero g and spells of gravity as the plane follows its parabolic flight path. For example at 1.30 he propels himself backwards and slightly upwards and then hits his head off the floor, so there's some gravity there. When the release the balls from the cases, they float in near zero g for a while but there's some slight changes of up and down motion which is due to changes in g force as the plane changes direction and then they all fall to the floor at the same time around 2.05. It's incredibly well done, but it's not three minutes of continuous zero g.

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34 minutes ago, biffer said:

If you know what you're looking for, what you can see in that video is spells of zero g and spells of gravity as the plane follows its parabolic flight path. For example at 1.30 he propels himself backwards and slightly upwards and then hits his head off the floor, so there's some gravity there. When the release the balls from the cases, they float in near zero g for a while but there's some slight changes of up and down motion which is due to changes in g force as the plane changes direction and then they all fall to the floor at the same time around 2.05. It's incredibly well done, but it's not three minutes of continuous zero g.

Exactly. It's fascinating trying to work out how they've choreographed it to the phases of the flight trajectory. God knows how you work it out in theory before putting it into practice (and I've no idea how they didn't all chuck up). Those stewardesses are brilliant.

I assume there would've been a number of takes, though the clean up between each one must've been murder.

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1 hour ago, phart said:

to be fair it's not zero G you're just falling.

welllllllllll.......

It becomes more complex than that because you have to consider the frame of reference you're talking about. When you say falling, you're always talking relative to another object that is also falling (the earth is falling towards the sun, the sun is falling towards the galactic centre, the galactic centre is falling towards the gravitational centre of the local group of galaxies etc etc). So how do you resolve that? There's no fixed point of reference that isn't falling in some way when you expand the point of view, and that point of view is then itself falling as well. This is what Einstein realised when he was formulating his General Theory of Relativity. Basically you get to the point that the frame of reference is the most important thing in observations and no particular frame is privileged. So in your own frame of reference it is zero g, because there's no ultimate frame of reference to compare yourself to. 

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Nah there is still plenty of gravity regardless of frame of reference. They're probably within a 100 miles of the surface of the planet. it's weightlessness they experience not zero gravity.

It's a point of pedantry anyway.

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1 hour ago, phart said:

Nah there is still plenty of gravity regardless of frame of reference. They're probably within a 100 miles of the surface of the planet. it's weightlessness they experience not zero gravity.

It's a point of pedantry anyway.

If your frame of reference is freely falling relative to where you're observing from, then there's no difference. You only consider it to have gravity because you're in another frame. 

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3 hours ago, phart said:

Nah there is still plenty of gravity regardless of frame of reference. They're probably within a 100 miles of the surface of the planet. it's weightlessness they experience not zero gravity.

It's a point of pedantry anyway.

It is a very important point of pedantry though. Scientists should always be discouraged from using the wrong terminology. It just confuses folk. Some of whom are already confused more than enough. Certainly on this thread anyway. :lol: As far as we are aware there is no place in the universe where there is no gravity. Biffer's Frame of Reference stuff is just irrelevant with respect to this discussion. 

http://www.yalescientific.org/2010/10/mythbusters-does-zero-gravity-exist-in-space/

 

2 hours ago, biffer said:

If your frame of reference is freely falling relative to where you're observing from, then there's no difference. You only consider it to have gravity because you're in another frame. 

 

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52 minutes ago, Orraloon said:

It is a very important point of pedantry though. Scientists should always be discouraged from using the wrong terminology. It just confuses folk. Some of whom are already confused more than enough. Certainly on this thread anyway. :lol: As far as we are aware there is no place in the universe where there is no gravity. Biffer's Frame of Reference stuff is just irrelevant with respect to this discussion. 

http://www.yalescientific.org/2010/10/mythbusters-does-zero-gravity-exist-in-space/

 

 

I honestly don't know if you're agreeing with both of us or telling us that we're both talking pish.

I don't like this sentence in that link though

However, the space shuttle never falls to the earth because it is traveling horizontally at about 18,000 km/hr, opposing the force of gravity. If the spacecraft was not moving quickly enough, it would fall prey to the effects of earth’s gravitational field and fall to the earth.

Orbiting is falling. It's just that you're travelling fast enough in a lateral direction to the centre of gravity you're falling towards that you continually miss and keep falling.

And given the amount of irrelevant pish there's already been on this thread, I don't feel particularly out of place.

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Apparently Gravity is explained in the flat earth 'model' by the fact the earth disc is rising at 9.81m/s. Come on do keep up!

it is not zero g. At best it is a simulation of zero g using free fall. Like sky diving without the wind as you are in the body of a plane. Free fall in a vacuum would be different to zero g how?

also is it not surface tension that explains why planets are spheres?

In orbit you are falling in free fall but you are moving laterally so fast that the earth falls away from you at a commensurate rate due to the curvature of the earth. Like you could climb a really high tower and fire a cannon horizontally off the top. If you shoot the cannon ball fast enough the earth would curve away from it as fast as it was falling. And that is all orbit is.

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If you found a perfectly round planet as smooth as a snooker ball with a perfect vacuum instead of an atmosphere could you not theoretically put a satellite in orbit one foot off the ground if fired at sufficient velocity? Or even a millimetre off the ground?

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2 hours ago, thplinth said:

If you found a perfectly round planet as smooth as a snooker ball with a perfect vacuum instead of an atmosphere could you not theoretically put a satellite in orbit one foot off the ground if fired at sufficient velocity? Or even a millimetre off the ground?

I'd think not. The moon has no atmosphere but you need to be at an altitude of around 60 miles from the surface to form a stable orbit...

https://en.m.wikipedia.org/wiki/Orbital_mechanics

 

 

Edited by Toepoke
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2 hours ago, biffer said:

I honestly don't know if you're agreeing with both of us or telling us that we're both talking pish.

I don't like this sentence in that link though

 

Orbiting is falling. It's just that you're travelling fast enough in a lateral direction to the centre of gravity you're falling towards that you continually miss and keep falling.

And given the amount of irrelevant pish there's already been on this thread, I don't feel particularly out of place.

Naw it's just you that's talking pish. And, I think you know that. I was agreeing with phart. You know fine well that there is nowhere in the universe (yet discovered anyway) where gravity does not exist. So stop talking about zero gravity and stop confusing folk more than they need to be. Is it any wonder that scientifically uneducated folk like Scotty get confused when scientists tell them that gravity exists everywhere then also try to get them to believe that somewhere, a bawhair from planet Earth,  you can have "zero gravity"

 

 

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17 minutes ago, Toepoke said:

I'd think not. The moon has no atmosphere but you need to be at an altitude of around 60 miles from the surface to form a stable orbit...

https://en.m.wikipedia.org/wiki/Orbital_mechanics

 

 

It's all relative. Relative to the Earth the moon has almost no atmosphere but it does have some.

 

https://www.nasa.gov/mission_pages/LADEE/news/lunar-atmosphere.html

 

Edited by Orraloon
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1 hour ago, Orraloon said:

Naw it's just you that's talking pish. And, I think you know that. I was agreeing with phart. You know fine well that there is nowhere in the universe (yet discovered anyway) where gravity does not exist. So stop talking about zero gravity and stop confusing folk more than they need to be. Is it any wonder that scientifically uneducated folk like Scotty get confused when scientists tell them that gravity exists everywhere then also try to get them to believe that somewhere, a bawhair from planet Earth,  you can have "zero gravity"

 

 

Aah, right. Hands up, I'd completely missed the point you guys were making about zero g. 

But the question thplinth asks

 

Free fall in a vacuum would be different to zero g how?

 

Is the point I was trying to make. There is no difference. 

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20 minutes ago, Scotty CTA said:

What does 'nasa' mean in Hebrew?

It doesn't mean anything. But you're probably about to twist the truth and say the word pronounced nacwah, which means to decieve, sounds exactly the same as NASA, which it doesn't. A closer foreign word to the pronunciation would be the Spanish nacer, which means to be born. 

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