Orbiting Issues

[vacantlook]

This is something I've thought about but have never been quite sure about.

So, Babylon 5 the station orbits the planet of Epsilon 3. The jumpgate is some distance away from the station and thus the planet. So, as the planet orbits around the local sun, Babylon 5 goes with the planet. Does the jumpgate go with them as they orbit around the sun? Does the jumpgate always stay in one place and the ships that come out of the gate just have to travel a much longer distance across the system to get to Babylon 5 some of the time? Or are there several jumpgates placed at opposite sides of the Epsilon 3 orbit?

 

[Jade Jaguar]

That's a good question! I had always assumed that the location of the jump gates was fixed, but it would seem to make more sense for them to stay at a fixed distance from any planets they served, that is, to orbit with the planet. Even if they did that, their relative position to B5 would change, as B5 orbits the planet, unless the jump gate orbited the planet in an orbit syncronized with B5.

 

[PillowRock]

Well, in the series I believe they tell us that a ship that is "hiding" behind the planet from the POV of the station (and/or ships entering or leaving the docking bays) is also "hiding" from ships going in and out of the jump gate. Or, at least there is an orbit that would be consistently "hiding" from both.

That would seem to indicate that the gate is orbiting in synch with the station. That would imply that it is at the same altitude as the station. Most likely, it would be in the same orbit, either leading or trailing the station by some distance / time (depending on how you think of it).

 

[sleepy_shadow]

as B5 orbits the planet

To my impression, B5 was "parked" at some Lagrange point between the planet and its star. This would mean it doesn't orbit around the planet... but travels together with it... somewhat closer to the star.

Where the gate could be... I cannot tell. Possibly orbiting the star as well... perhaps at a slightly different, neither too close nor too distant orbit from B5.

 

[sleepy_shadow]

Error admitted and corrected:

Since B5 occasionally enters the shadow of the planet... it cannot be located at any of the Lagrange points. Instead, it must quite conventionally orbit the planet.

 

[KoshFan]

We seem to have a script/visual effect continuity error....

 

[LondosHair]

You guys are forgetting one thing:

The Jumpgates operate on a beacon system. Obviously the gate is gonna have to orbit the star along with the planet, in a synchronous orbit so as to not drift away from the planet. In hyperspace, gates are connected and traveled-to via the beacon system.

I assume (since we've never seen an actual hyperspace beacon) that the beacon is a signal beamed thru hyperspace from one gate to another in a sort of "web" that ships travel along. I then assume that these beacons stay interconnected even while the gates themselves are in motion.

 

[Recoil]

We have a winner.

 

[Jade Jaguar]

It may well be as you say, but I don't see any reason it couldn't orbit the planet in a geosynchronus orbit, instead of orbiting the sun with the planet. Either one means it's physical location is constantly changing, which the beacon would have to deal with.

 

[vacantlook]

What level of impact does everyone thing the jumpgate being in motion would have on a ship when the ship comes through the jumpgate? With so much energy in the jumppoint, is it fully a computer guided maneuver?

Or, perhaps the jumpgate is stationary during the day when it's being used, but then when there is downtime and no ships are coming through it's moved to keep up with the orbiting of Epsilon 3.

Eek, I really don't know. It probably isn't something that the production folks of B5 put as much thought into as we have now.

 

[KoshFan]

Perhaps both the station and the jumpgate are both in geosynchronous orbits above the planet, just different ones.

 

[sleepy_shadow]

Few things in space... can remain stationary relative to each other, without wasting fuel. "Parking the gate" and then "unparking it" would be possible (maneuver into Lagrange point, manouver out again)... but rest assured, it would be a most unpractical and fuel-expensive activity.

While the gate may orbit around the planet... the planet definitely orbits around its star... and the star moves relative to other stars, while the universe expands. Certain motions remain regardless, and cannot be compensated for.

For a ship approaching a gate on beacon (imagining the approach to roughly resemble the B5 computer game IFH)... the gate moving wouldn't matter -- because it executes its maneuvers relative to the gate. While still in hyperspace, the captain may not even bother considering where in the solar system the gate happens to be.

Likewise when entering hyperspace. While constrained by engine power and possible orbits around massive bodies... the ship would simply enter an orbit similar to the gate... and maneuver into a reasonably clean entry.

That both would be orbiting other bodies... would not be their primary concern, except for course calculations (which would require adjustment, but a computer could accomplish that easily, and even if not, surely an experienced pilot could likewise).

 

[A_M_Swallow]

as B5 orbits the planet

To my impression, B5 was "parked" at some Lagrange point between the planet and its star. This would mean it doesn't orbit around the planet... but travels together with it... somewhat closer to the star.

I suspect that B5 was in the L5 Lagrange point between the planet and its moon. B4 would have been at L4 and the gate at L3. There is a plot error because the planet was not given a moon.

Given the hyperspace drift due to the planet going round its sun and the sun orbiting the milky way allowing for the gate going round the planet is only a tiny additional adjustment to the beacons.

 

[B5_Obsessed]

I believe JMS said the same thing, that B5 and the jumpgate were stationed at the Lagrange point between Epsilon 3 and its still unseen moon. So they would not move in relation to Epsilon 3, but would still orbit the sun relative to E3's own orbit. Under this scenario, I would think you would have B5 spending half an Epsilonian year in sunlight and half in shade. Maybe it's a really short year.

 

[B5_Obsessed]

Here's another thought: If Epsilon 3's rotation is matched to the orbit of it's moon, the B5 could orbit E3 from Lagrange and always be in the same position over E3. Either way, whether in orbit around the Epsilon 3, its sun, or around the galactic core, the gates are all moving.

Since hyperspace is shaped differently the normal space, it's probably irrelevant anyway. The beacons hold it all together no matter how much things shift on the outside.

 

[grumbler]

I believe JMS said the same thing, that B5 and the jumpgate were stationed at the Lagrange point between Epsilon 3 and its still unseen moon. So they would not move in relation to Epsilon 3, but would still orbit the sun relative to E3's own orbit. Under this scenario, I would think you would have B5 spending half an Epsilonian year in sunlight and half in shade. Maybe it's a really short year.

Planet-moon Lagrange points orbit the planet, of course, exactly as the moon does. I don't think the movement of the gate would have any effect on interstellar travel, as everything is in motion compared to everything else.

What works against the idea of the station and gate being at the L4 and L5 points is that the moon would be very nearly between them.

I think this is just one of those issues that was not completely thought out when the series started, and JMS has been kinda dancing around the answer ever since.

(Note: the station and gate cannot be at the same Lagrange point given the distance between them that we see. It is possible that the station is at a lagrange point in the Epilon-E3 system, ahead or behind the planet in its orbit, but distnaces to suc points from the planet would be large unless the sun was ultra-massive.)