[DIO]

Do we know if there is a FTL communication (somekind of subspace transmission?) in the Freespace universe?

[Droid803]

Probably.
3rd Fleet HQ can contact you in the nebula which is...who knows how far away from Capella in real-time.

[Krelus]

The real doozy is, why haven't they used it to contact Earth?

Hm, just thought of something, maybe the communication requires a functional node to work properly.

[Blue Lion]

Then would it be FTL then?

[Raskolnikov]

I've always assumed that communications were relayed through subspace.

The real question is, actually, why Earth hasn't contacted the GTVA via conventional means. Alpha Centauri is only ~20 light years from Sol (probably not precise, but you get the idea).

[Herra Tohtori]

I've always assumed that communications were relayed through subspace.

The real question is, actually, why Earth hasn't contacted the GTVA via conventional means. Alpha Centauri is only ~4 light years from Sol (probably not precise, but you get the idea).

Fix'd that for you. And yes it's a plot hole if any. It isn't explained how all contact to Earth can be lost - they should have started transmitting radio messages towards Earth from Alpha Centauri immediately, and gotten some kind of response eight years afterwards. Obviously it must be assumed that there hasn't been an answer, and that can be explained by quite a few ways though they fall in three main categories...

-Earth can't receive the signal. Unlikely considering the GTVA resources and technology, but still possible in case enough Shivan forces got through the node to bring Earth back to stone age or outright destroy the civilization. A case of "There's no one there to answer", if you will, although given the canon ending of Great War, I think the Shivans were eventually defeated by the First Fleet (and Alpha 1). An internal squabble developing into full scale war would also be possible...

-Earth can't transmit the signal. Similar scenarios on smaller scale could hypothetically lead to inability to transmit powerful enough signals to Alpha Centauri.

-Earth doesn't want to respond. There could be many reasons for this. Protectionist, corrupt government? Terran supremacy? Religious revolution? An external threat can easily be used by populistic politicians to get the population to sacrifice freedoms for "safety". It's possible that Earth and Sol system were overtaken by political agenda that does not see it beneficial for them to establish connections to GTVA. They might just be interested in increasing their military might so that if and when the gates to GTVA space open, they can take over and likely destroy or subdue the PVE instead of treating them as partners.


Just a few options...

[Blue Lion]

I may be making this up, but I seem to recall seeing something saying that signals like that just don't make it that far out.

[Herra Tohtori]

Why wouldn't they?

Laser would likely be the best option as far as signal strength is considered, but radio signals wouldn't be impossible to detect with, say, Arecibo or even better with the long base range interferometres (VLA or VLBA). And if they wanted to listen, they would definitely point them straight at Alpha Centauri all the time it was possible.

Not to mention that GTVA has all it's resources apart from Sol system to build as powerful a transmitter as they want, be it a laser, radio or a message capsule/unmanned ship making a long long series of intra-system jumps towards Sol starting from Alpha Centauri. What's the range of destroyer-class subspace drives within a system? Likely quite a bit considering ships jumping around systems like Capella which are HUGE compared to Sol system due to insanely large central star, so let's go with at least 100 AU.

One light-year is 63,241.1 astronomical units. Distance between Sol and Alpha Centauri is 4.37 ly which equals to 276363,607 astronomical units. That makes approximately 2764 100-AU jumps to reach Sol from Alpha Centauri.

If it takes 15 minutes to recharge the jump drives and five minutes to do the jump itself (it might even be instantaneous but we'll go with 20 minutes per jump), assuming there's enough fuel or energy or whatever and the ship holds together for that close to 3000 jumps, it would take about 55280 minutes to reach Sol. 921 hours. 39 days.

Intersystem drives in the long run can be faster than light on average assuming one jump range is longer than roughly 2 AU. 15 light-minutes (commonly used charge-time for jump drives) is about 1.8 AU.   I would safely say the ships in FS2 universe can do inter-system jumps longer than that without nodes. So it's not completely unplausible for GTVA to build a ship capable of reaching Sol - perhaps even in reasonable time frame. It probably all boils down to expense of construction of a ship with such vast energy reserves and reliable subspace drives that this was not attempted - even though it arguably could boost morale in the GTVA...

[FUBAR-BDHR]

It could be as simple as standard communications we think of being obsolete.  Without a jump node to send the message no one thought of sending or listening for an old style signal. 

It's also possible that the Shivans don't know the location of Sol.  Even if they knew Earth was on the other side of the node they may not have know where in space the node is.  Sending a signal could give them that information.  If you were on Earth after the attack would you risk it by transmitting? 

[blackhole]

Or it could just be a plot hole.

[Pred the Penguin]

It could be as simple as standard communications we think of being obsolete.  Without a jump node to send the message no one thought of sending or listening for an old style signal. 

That be like forgetting how to write because you type too much. -_-

I believe that the problem being on the Earth side is more plausible.
As for rest of the human race not sending someone there...DIK =/

[Kie99]

Why wouldn't they?

Laser would likely be the best option as far as signal strength is considered, but radio signals wouldn't be impossible to detect with, say, Arecibo or even better with the long base range interferometres (VLA or VLBA). And if they wanted to listen, they would definitely point them straight at Alpha Centauri all the time it was possible.

Not to mention that GTVA has all it's resources apart from Sol system to build as powerful a transmitter as they want, be it a laser, radio or a message capsule/unmanned ship making a long long series of intra-system jumps towards Sol starting from Alpha Centauri. What's the range of destroyer-class subspace drives within a system? Likely quite a bit considering ships jumping around systems like Capella which are HUGE compared to Sol system due to insanely large central star, so let's go with at least 100 AU.

One light-year is 63,241.1 astronomical units. Distance between Sol and Alpha Centauri is 4.37 ly which equals to 276363,607 astronomical units. That makes approximately 2764 100-AU jumps to reach Sol from Alpha Centauri.

If it takes 15 minutes to recharge the jump drives and five minutes to do the jump itself (it might even be instantaneous but we'll go with 20 minutes per jump), assuming there's enough fuel or energy or whatever and the ship holds together for that close to 3000 jumps, it would take about 55280 minutes to reach Sol. 921 hours. 39 days.

Intersystem drives in the long run can be faster than light on average assuming one jump range is longer than roughly 2 AU. 15 light-minutes (commonly used charge-time for jump drives) is about 1.8 AU.   I would safely say the ships in FS2 universe can do inter-system jumps longer than that without nodes. So it's not completely unplausible for GTVA to build a ship capable of reaching Sol - perhaps even in reasonable time frame. It probably all boils down to expense of construction of a ship with such vast energy reserves and reliable subspace drives that this was not attempted - even though it arguably could boost morale in the GTVA...

You can't make an intra-system jump when you're not in a system, it requires a gravity well.

[Herra Tohtori]

Are you quite sure about this?

Sauce plox.

[TrashMan]

Methinks Kie99 is right on this one.

Subspace drives do seem to require gravity wells.
All nodes are natural (even in-system ones, atlough they are everywhere so it's kinda of a moot point)

If there are no natural nodes between systems, then one can't use subspace drives to cross the space between systems (apart from nodes)

[Kie99]

Are you quite sure about this?

Sauce plox.

FS2 Techroom.

"First, an intrasystem jump can occur between two points in a star system. Most small, space-faring vessels are equipped with motivators capable of these short jumps. The presence of an intense gravitational field is required, prohibiting travel beyond the boundaries of a star system. "

[Herra Tohtori]

Thanks. Scratch that plan then...

[terran_emperor]

Also dont forget, Radio Signals are likely line-on-sight. If beaming from A-Centauri, You would need to know where Earth (or the Sol System) would be in four years time. And you would need precise co-ordinates, if you're off by even a fraction of a degree, you'd miss the system

From Alpha Centauri, Sol is part constellation Cassiopeia, near to Epsilon Cassiopeia. So thats a rough trajectory. But you need to aim where Sol would be in 4 years and not where it is now. For in four years, the system would have shifted slightly

Besides it is entirely possible that Mankind have forgotten how to use radio...I mean, the US military forgot how to make the F-14 Tomcat (or part of it) and in a recent fiasco forgot how to make a vital component for the Trident Missile

[StarSlayer]

FTL(and by that i mean magnitudes faster then light) comm is pretty much a necessity for FS2's Command to work

Brought up something similar here:
http://www.hard-light.net/forums/index.php/topic,51218.msg1035207.html#msg1035207

[The E]

Also dont forget, Radio Signals are likely line-on-sight. If beaming from A-Centauri, You would need to know where Earth (or the Sol System) would be in four years time. And you would need precise co-ordinates, if you're off by even a fraction of a degree, you'd miss the system

From Alpha Centauri, Sol is part constellation Cassiopeia, near to Epsilon Cassiopeia. So thats a rough trajectory. But you need to aim where Sol would be in 4 years and not where it is now. For in four years, the system would have shifted slightly

Besides it is entirely possible that Mankind have forgotten how to use radio...I mean, the US military forgot how to make the F-14 Tomcat (or part of it) and in a recent fiasco forgot how to make a vital component for the Trident Missile

Yeahno. Figuring out where Earth will be in 4 years time isn't that hard. In fact, programs like Celestia, or even Orbiter IIRC, can do that without a problem. Forgetting how to make a radio...I don't think so. Unless the GTVA transmits everything via FTL or hardline, I don't think they'd forget how to make a Radio. Hell, the basic technology for Radio communication is simple enough to reverse engineer, I guess that a civilization capable of building FTL-capable starships wouldn't have a problem with that. Your comparison to the US "forgetting" how to make spare parts for the F-14 or the Trident is badly chosen. If the US wanted to, they could have just taken apart one F-14 and reverse-engineer the part in Question, but instead they chose to retire the entire line and get a modern replacement. Same goes for the Trident issue, since the US didn't just become stupider over night, they still have the capability to reverse engineer the component in question.

[terran_emperor]

Okay.
I'm hesitant to quote Star Trek but if a radio message was sent, then there are two options: They are unable to respond or they are unwilling to respond.

Also
I never said the US had become stupider. I just said that its possible to forget how to make things using two examples that spang to mind