• Welcome! The TrekBBS is the number one place to chat about Star Trek with like-minded fans.
    If you are not already a member then please register an account and join in the discussion!

Babylon 5

Really fancy that encyclopaedia :( blast my other commitments.

Tonight’s episode is knives, the one with the baseball pitch. I’m not convinced you could play baseball in a centrifuge.
 
Yeah, I'm pretty sure the ball in flight down the length of the tube would describe an arc.
I mean arc to side as well as "down".

On the other hand, does centripital force even act on something that's not attached to the floor??
 
Last edited:
Yeah, I'm pretty sure the ball in flight down the length of the tube would describe an arc.
I mean arc to side as well as "down".

On the other hand, does centripital force even act on something that's not attached to the floor??
Well in this case I think the problem would be that the floor and the people standing on it are what's moving. The ball would essentially (but not really because it's inertial frame is still in an orbital trajectory around Epsilon 3) travel in a straight line, but from the perspective of the batter, it would appear to arc away from the spin of the cylinder.
Of course the pitching machine is computer controlled, so it could be programmed to compensate for this affect by adding some spin and aiming it at where the batter will be standing when the ball reaches them, rather than where they currently are.
 
Last edited:
...now I want to see a version where Sheridan can never hit the ball because it keeps arcing away from him.

"Sheridan to C&C, I'm going to need you to halt the station's rotation for the next thirty minutes; I want to get in some batting practice."
 
...now I want to see a version where Sheridan can never hit the ball because it keeps arcing away from him.

"Sheridan to C&C, I'm going to need you to halt the station's rotation for the next thirty minutes; I want to get in some batting practice."

How could he possibly hit the ball if he's floating around in zero-G? :lol:
 
Okay, I need a scientist now - if you throw a ball in the air in a rotating O'Neill cylinder, does it "fall" back, affected by the centripital force, or does it become weightless once it's no longer connected to the "ground"?
 
Okay, I need a scientist now - if you throw a ball in the air in a rotating O'Neill cylinder, does it "fall" back, affected by the centripital force, or does it become weightless once it's no longer connected to the "ground"?
You'll probably want to start here. ;)
 
The only force on a thrown baseball would be from the air around it, which is moving with the cylinder. It's been too long to try and do the math, but I'd imagine you'd end up with some wicked curve balls!
 
Okay, I need a scientist now - if you throw a ball in the air in a rotating O'Neill cylinder, does it "fall" back, affected by the centripital force, or does it become weightless once it's no longer connected to the "ground"?

I don’t think it would, and that got me thinking about the fountain on the zen garden. At first I imagined that the water would fall back in an arc, but there is reason to expect it it to fall at all. Like wise, I’d expect no flat water surfaces. Could you serve a pint of lovely ale with a frothy head without it trying to slosh out?

We know the central monorail thing was a microgravity area.,
 
The fountain would be a problem, since the water is being ejected away from the surface. Given the size of B5, flat water surfaces would probably be okay, except there would probably be a high evaporation rate, since most splashing would not fall back. An environment like B5 would probably be very humid. :rommie: Another factor that might make a difference, though, is air pressure which would be constantly "down," although I have no idea how much of a difference that would be.
 
I don’t think it would, and that got me thinking about the fountain on the zen garden. At first I imagined that the water would fall back in an arc, but there is reason to expect it it to fall at all. Like wise, I’d expect no flat water surfaces. Could you serve a pint of lovely ale with a frothy head without it trying to slosh out?

We know the central monorail thing was a microgravity area.,
Coriolis force would be an issue. To a good approximation, a ball would follow a straight line as seen by an outside non-rotating observer and a curved path by an internal rotating observer. A ball thrown straight up would appear to deviate to the antispinward direction. This also assumes that the ball is not rotating and so is not affected by the Magnus force, which would deflect the ball at right angles to its motion. The ball would not feel an effective gravitational force except perhaps a minor one through interaction with varying air density. Given sufficient room, air resistance would eventually halt the ball, at which point it would be only subject to forces due to air currents.

If you ran fast enough antispinward, you would beome weightless. Run spinward and you would effectively weigh more, although the effect diminishes toward your head, depending on your height in relation to the radius of rotation.

Fountains would be problematic although air resistance, water viscosity and surface tension should pursuade most of it to return to the fountain with a path determined by the Coriolis force. Someone has worked out what it might look like on this page:
http://www.science20.com/robert_inv...o_g_problem_and_answer_low_g_questions-129424
Search on the page for fountain. The whole page should answer many of your questions.
See the following dissertation for more details:
http://www.artificial-gravity.com/Dissertation/FrontMatter.htm
 
Last edited:
Coriolis force would be an issue. To a good approximation, a ball would follow a straight line as seen by an outside non-rotating observer and a curved path by an internal rotating observer. A ball thrown straight up would appear to deviate to the antispinward direction. This also assumes that the ball is not rotating and so is not affected by the Magnus force, which would deflect the ball at right angles to its motion. The ball would not feel an effective gravitational force except perhaps a minor one through interaction with varying air density. Given sufficient room, air resistance would eventually halt the ball, at which point it would be only subject to forces due to air currents.

You are correct, although it's important to note that the ball will appear to fall on to the floor again from the POV of an observer standing on floor. I don't think that's clear from your post (no offence!).

While the ball doesn't have any real gravity acting upon it, being at apparent rest in the rotating frame means the ball is actually travelling in a circle at the tangential velocity of the cylinder's outer edge. Since things naturally want to travel in straight lines, when I throw the ball up, it will still be carrying that speed but start to follow a straight line path, and that straight line will take it back out to the edge of the cylinder, making it look like it's fallen back down again to the floor.

As an observer standing on the space station's deck, I too will be moving with the same speed, but still following the circle path (since I'm still being pushed by the floor). This means that as you say, it won't go straight up or come straight down again from my point-of-view. Working out the difference is complicated, and accounts for what we call the Coriolis force.
 
Last edited:
Nice. That should make flying cars, and even human-powered flight, pretty easy on a space habitat.
 
Here's another video about simulated and artificial gravity in Sci-Fi. Babylon 5 section from 7:15 onwards.

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

I watched The Gathering over the weekend. It was fun to see the 'beta' versions of G'Kar and Delenn's alien makeup. I sure am glad about the eventual tweaks they did.

I'm still pondering how it's possible to poison a Vorlon. I'm guessing that our shapeshifter may well be an agent of the Shadows, and obtained the poison from them. I'm supposing that all the Doctor actually did was to remove the poison patch from Kosh and Kosh probably recovered largely on his own; I can't imagine the medlab is set up to handle million year old energy squids.
 
Last edited:
...maybe Kosh was faking it the whole time?

Certainly possible too. Sinclair/Valen may well have told him how the whole thing played out after he went to the past where they knew each other, and Kosh was simply acting his part, to avoid a temporal paradox.

Alternatively, perhaps the whole thing was staged to get Lyta Alexander to read Kosh, setting her up for further 'modification' later.
 
If you are not already a member then please register an account and join in the discussion!

Sign up / Register


Back
Top