Sorry to be so geeky, but Space 220 has gravity all wrong

[sponica]

This is the best thread since the "endgame time travel is all wrong" battles of 2019.

I tip my hat to you.

I am however looking forward to my "trip" to the space station in less than 3 weeks!

 

[HydroGuy]

I'm not arguing with you, because I am not an expert, but Elon Musk's Starlink satellites are claimed to be in Low Earth Orbit, and they are orbiting, not just falling out of the sky. Why would a space station be any different?

If the only issue is not the orbit but the exact "mileage" above the earth, then I guess we will have to pretend the elevator is longer - since in real life it only goes 220 miles. I know. I was on it.

The satellites in low earth orbit are traveling at 17,000 mph in a circular orbit around the earth. In simple terms, this gives them a centrifugal acceleration of V*V/r. At just the right velocity, V, this acceleration will balance that from gravity. This is what makes a stable orbit. It feels like zero-g because the high orbital velocity negates gravity. That stable velocity in Low Earth Orbit is about 17,000 mph. It depends on what "r" is which relates to how far you are above the Earth.

The orbital velocity of Space 220 is zero relative to the Earth. Any object at 220 miles up moving slower than the 17,000 mph will fall towards the Earth. And higher velocity will move away from the Earth. Space 220 is slower than 17,000 mph. It is zero. No difference than going up in a balloon really high then jumping out. You will fall back to the Earth because of gravity.

You can simulate zero-g on Earth in an airplane traveling in a very precise parabolic pattern. That is what the "Vomit Comet" does I linked earlier. As I recall they used the Vomit Comet to simulate zero-g when filming the Apollo 13 movie. And others.

https://www.space.com/37942-vomit-comet.html

 

[J-Dog]

The satellites in low earth orbit are traveling at 17,000 mph in a circular orbit around the earth. In simple terms, this gives them a centrifugal acceleration of V*V/r. At just the right velocity, V, this acceleration will balance that from gravity. This is what makes a stable orbit. It feels like zero-g because the high orbital velocity negates gravity. That stable velocity in Low Earth Orbit is about 17,000 mph. It depends on what "r" is which relates to how far you are above the Earth.

The orbital velocity of Space 220 is zero relative to the Earth. Any object at 220 miles up moving slower than the 17,000 mph will fall towards the Earth. And higher velocity will move away from the Earth. Space 220 is slower than 17,000 mph. It is zero. No difference than going up in a balloon really high then jumping out. You will fall back to the Earth because of gravity.

You can simulate zero-g on Earth in an airplane traveling in a very precise parabolic pattern. That is what the "Vomit Comet" does I linked earlier. As I recall they used the Vomit Comet to simulate zero-g when filming the Apollo 13 movie. And others.

https://www.space.com/37942-vomit-comet.html

Gotcha. Thanks for the explanation! So, if Space220 beamed us up like Star Trek, instead of an attached elevator, then it would possibly be feasible, if the orbit speed was correct, right?

 

[HydroGuy]

Gotcha. Thanks for the explanation! So, if Space220 beamed us up like Star Trek, instead of an attached elevator, then it would possibly be feasible, if the orbit speed was correct, right?

Yes. But then Space 220 would be orbiting the Earth every 90 minutes or so. And not stationary over Central Florida. That would be cool, but would require constant adjustments of the view out the Space 220 windows to maintain realism. And the artificial gravity would definitely be needed!

 

[B-Ride]

You worry about the gravity or lack thereof. I'll worry about the price.

 

[_19disnA]

Space 220 is a pretend visit to outer space. I don't get hung up over the science aspects like 'how did we get here?' and just enjoy the illusion/make-believe part Disney is creating ................but to each their own.

 

[jimmymc]

I did notice as well, the restaurant is moving slow enough that it would quickly fall out of the sky. Geostationary orbit is about 22,000 miles away, which would make the Earth look like a beach ball floating outside the window. I'm just gonna suppress these facts if I ever eat there.

 

[Micca]

Ah geez, when anyone brings up gravity it just brings everybody down.

 

[lovethesun12]

Gotcha. Thanks for the explanation! So, if Space220 beamed us up like Star Trek, instead of an attached elevator, then it would possibly be feasible, if the orbit speed was correct, right?

Wouldn't the altitude just always be 22,000 miles for that? I use orbital speed = sqrt (Gm/r) and equate to
orbital speed = 2*pi*r/T for Earth

You end up with r^3 = GmT^2/(4pi^2) where m is mass of the earth

 

[HydroGuy]

Wouldn't the altitude just always be 22,000 miles for that? I use orbital speed = sqrt (Gm/r) and equate to
orbital speed = 2*pi*r/T for Earth

You end up with r^3 = GmT^2/(4pi^2) where m is mass of the earth

Not sure what you are asking. The 22,000 mile altitude is for geostationary orbit. In Low Earth Orbit you need a much higher orbital velocity to maintain a stable orbit.

 

[jbish]

I appreciate this post as this is not something I would know, at all. But very good info! Love it.

 

[glocon]

Very interesting, I love hearing that geeky kind of stuff! But it wouldn’t mar my enjoyment of the restaurant in the least. I can’t wait to try it someday. Just something fun and different.
Since it’s EP, it would be cool to have info posted somewhere on this kind of thing, some educational info somewhere…

 

[joyjoy]

Now this is coming from the idiot that signed up for Astronomy 301 in college thinking is was ASTROLOGY, so there ya go.... but I find this observation and commentary very interesting and appreciate the knowledge out there. Thank you!

 

[mistysue]

Please tell me somebody else has wondered if the person who named it space 220 got their numbers wrong from 22,000?

This whole thread is disappointing me, but only because I expected that the view would keep changing, not that you had a constant view of Florida. Who wants to stare at Florida for an hour while you're clearly trying to escape it?

 

[Mango7100]

I did a quick search to see if any fellow geeks out there had mentioned this already and did not see any threads on it.

I was fortunate to get an ADR for Space 220 last Saturday. My first time there. The whole experience is really cool. But they have their physics wrong! Any other tech geeks out there notice? Didn't anyone at Disney check with someone who knows their orbital mechanics? Heck, Space 220 is right next to Mission Space which had tons of input from NASA!

We were informed when we got on the space elevator that they had the "artificial gravity" working on Space 220. But one would not need artificial gravity on Space 220. When you are at 220 miles above Earth there is gravity. However, if you are moving at a high enough orbital velocity the centrifugal force would balance out the gravitational force - this would create a net zero-g and you would be floating like on the Space Station. That required orbital velocity is roughly 17,000 mph at 220 miles above Earth - the same velocity as any satellite orbiting the earth at 220 miles up. For the record, the formula is V*V/r where V is the orbital velocity and r is the radius of the orbit. r is not 220 miles but the distance to the Earth center - about 220 + 4,000 miles (actually about 3,959 miles) where 3,959 is the approximate radius of the Earth.

But Space 220 does not orbit the Earth. It is a space elevator and so rotates with the Earth. That is why the view out the Space 220 window never changes and you always remain over Central Florida. Gravity on Space 220 would be roughly the same as it is on Earth - near enough that you would not notice.

The floating astronauts in zero-g out the windows? They would not float. They would fall to Earth the same as on Earth's surface. They would need jet packs to stay floating outside the windows the same as they would out the window of your house.

I told my wife all this while we were on Space 220 but she was not impressed and thought I was ruining it all. Oh well!

Showed this to my engineer husband and he said “this guy is 100% correct”. And he too would bring these facts up during dinner while I’m just trying to look at the pretty stars

 

[CarolynFH]

Please tell me somebody else has wondered if the person who named it space 220 got their numbers wrong from 22,000?

This whole thread is disappointing me, but only because I expected that the view would keep changing, not that you had a constant view of Florida. Who wants to stare at Florida for an hour while you're clearly trying to escape it?

Supposedly you’re in a space station 220 miles above the earth. I thought it was supposed to be tethered to the earth, which is why you take an elevator to get there, not a rocket ship, and the view doesn’t change except for day/night. The fun is what’s going on outside the windows - space golf, walking the dog, lightsaber fights!

 

[HydroGuy]

Please tell me somebody else has wondered if the person who named it space 220 got their numbers wrong from 22,000?

This whole thread is disappointing me, but only because I expected that the view would keep changing, not that you had a constant view of Florida. Who wants to stare at Florida for an hour while you're clearly trying to escape it?

The view is not really "of Florida" but "from above Florida". You see a large part of the USA and the blue haze along the earth surface is very cool.

No, no one got their 22,000 and 220 mixed up. The view from 22,000 would be very different. A changing view would be cool but that could not be done from a fixed space elevator.

 

[chiburple]

Next time you visit, just pretend the mass of the Earth is significantly less. That should resolve the problem

... Although I suppose you might wonder why we have such strong muscles if we live in a lower gravity environment... we're visiting aliens? And the restaurant is designed to cater to humans?

 

[DisneyCowgirl]

I love this post. And I'm going to use this knowledge to annoy my family when we finally get a reservation there!

 

[suemom2kay]

I’ll just eat a churro next time I’m in the Mission Space line. Same effect, much cheaper price.