Technical question about 2001: A Space Odyssey

[NFS4]

So, my wife took me to see Gravity for my birthday last week, and I thoroughly enjoyed it. So on my plane ride to Vegas this week, I decided to revisit 2001: A Space Odyssey.

Two things stuck in my mind while watching, one of which has been resolved.

1) I thought that your body would immediately freeze in a vacuum (when Dave blows the hatch to enter the airlock) or some crazy shit like that. But after doing some minor research, it appears that the human body can survive in space's vacuum without ill effects or losing consciousness for about 12 seconds -- as long as you don't hold your breath. So that one is solved.

But...

2) Discovery is not in orbit, but on (I'm assuming) a linear trajectory towards Jupiter, traveling at great speed. However, how do the pods travel in and out of the Odyssey and Bowman/Poole just float/dart towards the antenna array with no (significant) power of their own if the ship itself is moving? I mean Discovery has some massive nuclear reactor engines; there's no way that a pod or a man could keep up, right?

Now granted, I don't recall either powering down the ship or putting on the parking brake So perhaps I missed that part.

Sorry if these are stupid questions, but it's just something I've wondered about since most experts say that with the exception of a few minor foibles, this movie was incredibly accurate scientifically.

 

[Jeff7]

The pod and astronauts are already traveling at the same speed as the ship, so they don't need to do anything to continue moving at that speed.



TV shows and some movies are the only places where space has the consistency of warm molasses, where anything without working engines immediately grinds to a halt.



Right now, Earth is moving around at an impressive speed, yet if you jump off the ground, you don't suddenly slow to 0mph relative to space itself since you're no longer touching the ground. You continue moving right along with Earth, and fall back down to the spot you were just standing on.

Or let's say one of the Voyager spacecraft, drifting rapidly away from the Solar System, was to suddenly split in two.
- Voyager doesn't have any "engine" to speak of anyway, just a few maneuvering thrusters to keep it pointing the right way.
- The two halves would continue moving along at high speed, side-by-side.

 

[Rakehellion]

1) I thought that your body would immediately freeze in a vacuum

Your body can't freeze in a vacuum since there's no surrounding cold air.

 

[NFS4]

Your body can't freeze in a vacuum since there's no surrounding cold air.

That's not what Sci-Fi movies told me

 

[Blitzvogel]

Your body can't freeze in a vacuum since there's no surrounding cold air.

Certainly in the shadow of something large, the water in your body will freeze because there is no energy being imparted to it if not exposed to the sun. It won't happen instantaneously.

 

[smackababy]

The pod and astronauts are already traveling at the same speed as the ship, so they don't need to do anything to continue moving at that speed.
Objects in motion...



TV shows, and some movies, are the only places where space has the consistency of warm molasses, where anything without working engines immediately grinds to a halt.

This. Once you've broken the immediate gravity around Earth (and Jupiter on the way back), you need very little energy to move through space.

 

[Leros]

http://science.howstuffworks.com/question540.htm

Besides the lack of oxygen, it sounds like the biggest problem is that bodily fluids would start boiling due to the lack of pressure.

In regards to boiling due to lack of pressure, that page also says:

This process could take from 30 seconds to 1 minute. So, it was possible for astronaut David Bowman in "2001: A Space Odyssey" to survive when he ejected from the space pod into the airlock without a space helmet and repressurized the airlock within 30 seconds.

 

[Jeff7]

Your body can't freeze in a vacuum since there's no surrounding cold air.

Yes it can.

- Evaporative cooling will start immediately, as the moisture on your skin and eyes will boil away. (Lower the pressure, and the boiling point of water drops.) That will cool you down a good bit.
- Radiative cooling. This works much more slowly than convective or conductive cooling, but eventually you'll cool way down.

Pluto is not immersed in any kind of fluid, yet it had no problem becoming extremely cold.



Plop someone into intergalactic space, which is about as empty as you can get, and their body will head toward a temperature in line with that of the microwave background radiation, not too terribly far from absolute zero.

 

[NFS4]

Yes it can.

- Evaporative cooling will start first, as the moisture on your skin and eyes will try to boil away. (Lower the pressure, and the boiling point of water drops.) That will cool you down a good bit.
- Radiative cooling. This works much more slowly than convective or conductive cooling, but eventually you'll cool way down.

From the "goofs" articles I've read on Gravity,

Spoiler

the bodies of the space shuttle crew members would have frozen, but not as quickly as depicted in the movie. It would have taken a few hours.

 

[bryanl]

2) Odyssey is not in orbit, but on (I'm assuming) a linear trajectory towards Jupiter, traveling at great speed. However, how do the pods travel in and out of the Odyssey and Bowman/Poole just float/dart towards the antenna array with no (significant) power of their own if the ship itself is moving? I mean Odyssey has some massive nuclear reactor engines; there's no way that a pod or a man could keep up, right?

Now granted, I don't recall either powering down the ship or putting on the parking brake So perhaps I missed that part.

The First Law of motion also explains why jumping inside a flying 747 doesn't make you slam into the back of the cabin.

The spacecraft was Discovery, not Odyssey, and its main propulsion was from atomic bombs exploding behind it, a fact downplayed in the movie due to Kubrick then-recent association with that nuclear comedy, Dr. Strangelove.

 

[smackababy]

The First Law of motion also explains why jumping inside a flying 747 doesn't make you slam into the back of the cabin.

The spacecraft was Discovery, not Odyssey, and its main propulsion was from atomic bombs exploding behind it, a fact downplayed in the movie due to Kubrick then-recent association with that nuclear comedy, Dr. Strangelove.

They also left a lot of stuff out, such as the explanation of what exactly the black stone was or did. It was a good movie, but the books (along with the rest in the series) really go so far beyond what Kubrick could have imagined on film.

 

[Leros]

They also left a lot of stuff out, such as the explanation of what exactly the black stone was or did. It was a good movie, but the books (along with the rest in the series) really go so far beyond what Kubrick could have imagined on film.

I'm about 20% of the way through the book. The explanation of the black stone was certainly interesting. I already understand a lot more about the movie.

 

[Jeff7]

From the "goofs" articles I've read on Gravity,

Spoiler

the bodies of the space shuttle crew members would have frozen, but not as quickly as depicted in the movie. It would have taken a few hours.

I've not seen Gravity, so I don't know what went on there.:\


In any case, some information about radiation:

Everything in the Universe with a temperature above absolute zero emits electromagnetic radiation.
The Sun emits some that's in the visible spectrum, along with a whole lot of stuff we can't see.
Some things emit extremely energetic gamma radiation for a short time.
You can heat up steel until it starts to glow visibly, but most of its radiation is being emitted in infrared. That red glow is just the tiny portion of the emitted radiation that's peeking through into the region that we can see.
You radiate infrared, as does you car, and your house, snow outside, the ground, everything. Temperature dictates what wavelengths an object will emit.

So if you're sitting in a box, you're emitting infrared at the box, and the box, since it's also hopefully well above absolute zero, is emitting infrared back at you. Since you're likely warmer than the box, you're going to be losing a small amount of heat to the box.
If that box were heated up, its emitted infrared would exceed what you were putting out, so it would then heat you up.
It's simply the result of things trending toward equilibrium.

In space, you're surrounded by a whole lot of microwave background radiation, and a lot of very tiny pockets of hot matter (stars). But it's mostly empty and cold, less than 3 degrees Kelvin. You are more than 300K. So your body is going to experience a net loss of energy to the cosmic background.

 

[William Gaatjes]

The pod and astronauts are already traveling at the same speed as the ship, so they don't need to do anything to continue moving at that speed.



TV shows and some movies are the only places where space has the consistency of warm molasses, where anything without working engines immediately grinds to a halt.



Right now, Earth is moving around at an impressive speed, yet if you jump off the ground, you don't suddenly slow to 0mph relative to space itself since you're no longer touching the ground. You continue moving right along with Earth, and fall back down to the spot you were just standing on.

Or let's say one of the Voyager spacecraft, drifting rapidly away from the Solar System, was to suddenly split in two.
- Voyager doesn't have any "engine" to speak of anyway, just a few maneuvering thrusters to keep it pointing the right way.
- The two halves would continue moving along at high speed, side-by-side.

If you jump straight up and can stay in the air for a while, because of the rotation of the earth... you would still end up at another spot when falling back to the earth.

But if you would really jump straight up and could stay in the air for a while before falling back, even with gravity and the rotation, should still have some displacement because the earth is moving under neath you ? The displacement would be the rotation and the moving of the earth through space beneath you even though the earth's gravity is pulling you back down. It would be tiny compared to the rotation and because of the gravity pulling you down but should be there...
At least that is the gut feeling i have.

http://www.scientificamerican.com/article.cfm?id=how-fast-is-the-earth-mov

Thus, the surface of the earth at the equator moves at a speed of 460 meters per second--or roughly 1,000 miles per hour.

As schoolchildren, we learn that the earth is moving about our sun in a very nearly circular orbit. It covers this route at a speed of nearly 30 kilometers per second, or 67,000 miles per hour.

 

[NFS4]

The First Law of motion also explains why jumping inside a flying 747 doesn't make you slam into the back of the cabin.

The spacecraft was Discovery, not Odyssey, and its main propulsion was from atomic bombs exploding behind it, a fact downplayed in the movie due to Kubrick then-recent association with that nuclear comedy, Dr. Strangelove.

**Fixed**

I guess I was just thinking about it from the perspective of being on earth, and not space. For example, jumping out of a plane, where you have outside forces affecting you vs being outside of gravitational pull.

It just seemed odd (to me at least) reasoning in my brain Frank hopping out of the pod towards the dish.

 

[K1052]

The spacecraft was Discovery, not Odyssey, and its main propulsion was from atomic bombs exploding behind it, a fact downplayed in the movie due to Kubrick then-recent association with that nuclear comedy, Dr. Strangelove.

My recollection was that it was advanced version of the NERVA engine.

 

[Number1]

So, my wife took me to see Gravity for my birthday last week, and I thoroughly enjoyed it. So on my plane ride to Vegas this week, I decided to revisit 2001: A Space Odyssey.

Two things stuck in my mind while watching, one of which has been resolved.

1) I thought that your body would immediately freeze in a vacuum (when Dave blows the hatch to enter the airlock) or some crazy shit like that. But after doing some minor research, it appears that the human body can survive in space's vacuum without ill effects or losing consciousness for about 12 seconds -- as long as you don't hold your breath. So that one is solved.

But...

2) Discovery is not in orbit, but on (I'm assuming) a linear trajectory towards Jupiter, traveling at great speed. However, how do the pods travel in and out of the Odyssey and Bowman/Poole just float/dart towards the antenna array with no (significant) power of their own if the ship itself is moving? I mean Discovery has some massive nuclear reactor engines; there's no way that a pod or a man could keep up, right?

Now granted, I don't recall either powering down the ship or putting on the parking brake So perhaps I missed that part.

Sorry if these are stupid questions, but it's just something I've wondered about since most experts say that with the exception of a few minor foibles, this movie was incredibly accurate scientifically.

Unless the ship is accelerating or decelerating, objects moving in or out of the ship will travel at the same speed and the same direction as the ship. Remember that there is no friction in space.

 

[Jeff7]

If you jump straight up and can stay in the air for a while, because of the rotation of the earth... you would still end up at another spot when falling back to the earth.

But if you would really jump straight up and could stay in the air for a while before falling back, even with gravity and the rotation, should still have some displacement because the earth is moving under neath you ? The displacement would be the rotation and the moving of the earth through space beneath you even though the earth's gravity is pulling you back down. It would be tiny compared to the rotation and because of the gravity pulling you down but should be there...
At least that is the gut feeling i have.

http://www.scientificamerican.com/article.cfm?id=how-fast-is-the-earth-mov

You're also moving at the speed of the surface of the rotating planet, so you've got that momentum, and you're also bound by its gravitational field.


Once you jump off, your momentum will want to carry you in a straight line that is tangential to the surface of the planet. The ground also "wants" to do the same thing, but it can't, since it is bound to the rest of the planet, so its path is a circular one.
So yes, you would land in a slightly different spot. But because of the immense difference between the size of your jump versus the diameter of the planet, and the brief duration of the jump, any difference caused by the difference in directions of travel (straight line versus circular), it's small enough that I'd consider it to not matter. In the same way, I don't account for relativistic effects in daily life, because the effect is so minimal that it doesn't really matter.

If I was building something with the precision of the Large Hadron Collider, maybe then I'd be concerned about it.

 

[William Gaatjes]

You're also moving at the speed of the surface of the rotating planet, so you've got that momentum, and you're also bound by its gravitational field.


Once you jump off, your momentum will want to carry you in a straight line that is tangential to the surface of the planet. The ground also "wants" to do the same thing, but it can't, since it is bound to the rest of the planet, so its path is a circular one.
So yes, you would land in a slightly different spot. But because of the immense difference between the size of your jump versus the diameter of the planet, and the brief duration of the jump, any difference caused by the difference in directions of travel (straight line versus circular), it's small enough that I'd consider it to not matter. In the same way, I don't account for relativistic effects in daily life, because the effect is so minimal that it doesn't really matter.

If I was building something with the precision of the Large Hadron Collider, maybe then I'd be concerned about it.

As a huge nerd, i was thinking jump coordinations when teleporting.

 

[lupi]

near instant boiling of your body doesn't sound pleasant.

 

[Jeff7]

near instant boiling of your body doesn't sound pleasant.

Nah, not the whole body, only whatever's exposed to the reduced pressure. :awe:

 

[NFS4]

near instant boiling of your body doesn't sound pleasant.

 

[BarkingGhostar]

Well, so much for everyone's understanding of 'fiction'.

 

[smackababy]

my name is not quaid!!!!!!!