Sci-fi FTL and hyperspace jumps and their worries

[Nick20]

I didn't really know where to put this, so I just put it here.

What I wanted to discuss was the following:
often in sci-fi movies or series they have the capability to travel faster than light one way or another. Whether it is by means of FTL, hyperspace, wormholes or whatever they always seem to have this to worry about. "We need to do a proper jump calculation, or else we could end up in a star". I hear that a lot, and it got me thinking: if you just pick any coordinates by random, how big is the chance that you'll end up in some star? Because in my head there's a lot of space that is not occupied by a star. So in an emergency situation, is the chance of ending up in a star really too high to take the risk?

I don't know if anyone else have thought of this, but when I first noticed it really puzzled me.

Nik

 

[Vanadium 50]

This is what is called a "plot device". The purpose of science fiction is to tell a story.

 

[Ryan_m_b]

Space is really big and really empty. The chance of a random jump appearing in a star or anything is highly improbable. Such limitations are plot devices, normally to stop the protagonists from making convenient exits or getting from place to place to quickly. Some science fiction will attempt to justify this further, for example it might be written that the FTL used can take the crew wildly off course (requiring more jumps, more fuel, more time etc to arrive at the destination) and spending time refining the calculations will result in a better jump.

In the end though it is just a convention. A useful one of course, and one that should be justified properly to make the SF good.

 

[Vanadium 50]

Do you really think the justification is necessary? Consider a spy thriller, where our heroes need to get from St. Louis to London as quickly as possible. Do they need to discuss how there are no morning flights because the time difference would get them there in the middle of the night, or how there are no direct flights since TWA was absorbed by American Airlines?

 

[lurflurf]

We do not know the details of the FTL. Perhaps besides wanting the endpoint to be satisfactory there are all sorts of other restrictions. Such as not passing near any stars. Maybe the nature of the FTL makes ending up in a star more likely than the star density suggests. For example maybe a random endpoint is weighted by the mass so a random point in this solar system has a 99.9% chance of being in or near the sun.

 

[Nick20]

Do you really think the justification is necessary? Consider a spy thriller, where our heroes need to get from St. Louis to London as quickly as possible. Do they need to discuss how there are no morning flights because the time difference would get them there in the middle of the night, or how there are no direct flights since TWA was absorbed by American Airlines?

no, sorry, I'm not too good at explaining exactly what I mean. This is why I was not quite sure where to put this. I'm not looking for any justification, I know what it is, why they use it. I really just wanted to take that idea into the real world and see how it really is.

 

[Nick20]

We do not know the details of the FTL. Perhaps besides wanting the endpoint to be satisfactory there are all sorts of other restrictions. Such as not passing near any stars. Maybe the nature of the FTL makes ending up in a star more likely than the star density suggests. For example maybe a random endpoint is weighted by the mass so a random point in this solar system has a 99.9% chance of being in or near the sun.

Very good point, this is the kind of answer I was looking for. Thank you.

 

[GTOM]

In my W40k story i said, no you can't jump within an hour, otherwise atomic structure will collapse, and it isn't more punctual than Earth to Moon distance, you can't jump into the back of the other starship.

 

[cpscdave]

I don't know if ending up in a star is likely.. But geting lost is extremely likely.

Think about traveling along a straight path from point A to point B. The longer the distance the more accurate you need to be to end up where you intend. If you're going to travel a couple hundred light years how many decimal points of acuracy do you need to end up where you want?

So then suppose you do make a mistake and you travel along a slightly different trajectory. All you know is your starting point and aproximatly how far you traveled and that you're not where you intended. So how are you going to locate yourself in space now?

 

[GTOM]

"So how are you going to locate yourself in space now? "

Watching star constellation of the Galaxy isn't a bad start.

Otherwise i like this idea : "For example maybe a random endpoint is weighted by the mass so a random point in this solar system has a 99.9% chance of being in or near the sun."
You might speculate in the fictional work, that hyperspace looks like an unstretched universe, masses are crammed together.
Although this rather means, that travel should like you just disappear and reappear into real space (with max jump distance and minimum time between jumps limits your max speed), not going through some hypertunnel.