Saga Lightspeed Calculations

Hello there!

In ANH Han said:

I believe the nav-computer could calculate other stuff like the planets orbits throughout the path, as well as moons, black holes and comets, since it all could be mapped and constantly be synchronized like our clocks through time-servers over the internet.

But... What about those other little things that could crash along the way?

I mean asteroids and other ships. It's possible, however unlikely, 2 ships in lightspeed could crash each other. However it's quite probable a ship could collide to asteroids..... They flow in random directions, right?

We've seen a lightspeed crash in TFA: It was the Falcon against the rathtar. The monster got disintegrated, while the Falcon didn't suffer any damage. Why not?

IN R1 K2-SO: said:

And Cassian replied:

I believe Cassian was willing to risk a crash since awating for the complete calculation would mean death instantly. But he could have gone out of lightspeed and make a proper calculation as soon as possible, right? But we've never seen it happen...

All right, those calculations could be just a plot device. But it's certainly a plot hole, isn't it?

 

Asteroids don't move randomly - but in orbits - though those orbits can shift a bit due to perturbation from the gravity of other objects.

I suspect that "hyperspace drop-out" places are always some way away from asteroid fields, to minimise risks, though. Sublight engines would be used to pilot around asteroid fields, if they're dense enough to "block the way" - through them if the delay by going around is not acceptable, and the risks are minimal (some fields are denser than others).

Shields probably help too - according to the ANH novel, the Falcon's shields deflected the few asteroids from exploded Alderaan that actually hit it.

 

Yes, you are right about minimising the risks.

And I agree that asteroid FIELDS follows some orbit. But it's quite common on space that a body's escape speed overcomes the gravity of a bigger body. I mean, our own Moon is getting more and more away from Earth. It eventually will escape from Earth. So asteroids can flow independently through the galaxy until it gets arrested into some gravity. Lots of asteroids hits both Moon and Earth, coming from their own routes.

And about the shields, I believe they work better when the ships are moving in lower speeds. The Falcon could hold some laser beams when it was NOT at lightspeed. The beams are not at lightspeed. Following the

F = m x a formula, the force impact of an asteroid when the ship is at lightspeed would require an almost indestructible shield.

 

Thom Skywalker wrote

I believe the nav-computer could calculate other stuff like the planets orbits throughout the path, as well as moons, black holes and comets, since it all could be mapped and constantly be synchronized like our clocks through time-servers over the internet.

But... What about those other little things that could crash along the way?

I'm rather confident that smaller space debris like asteroids or else (e.g. junk dropped by Imperial Star Destroyers) doesn't really concern or affect hyperspace travel, i.e. that stuff is too small to affect objects that are flying within hyperspace.

However, the immense gravity of star or the fast moving shock wave of a supernova apparently do affect hyperspace and therefore any object travelling within.

Because Solo was traveling from the Outer Rim towards the dense region of the core worlds, his calculations needed to be precise, but I'd speculate that hyperspace jumps from the core worlds to regions like the Outer Rim require less meticulous preparations.

 

Remember when the Falcon arrives at Alderaan, Han is surprised to be landing right in the middle of what he initially thinks is an asteroid field. The latest star charts would note if there was an asteroid field in orbit of Alderaan. Then it occurs to him when he checks the scanners that it isn't an asteroid field, but something else. When we watch AOTC, Jango is well aware of the asteroid field surrounding Geonosis and thus prepared Slave I to drop out ahead of the field.

I wager that every so often, these lanes are checked to see if anything has changed by normal means. Black holes and novas would be recorded and notations made for future travel.

 

Actually he believes it might be some kind of asteroid collision.

HAN What the...? Aw, we've come out of
hyperspace into a meteor shower.
Some kind of asteroid collision.
It's not on any of the charts

His last sentence indicates indeed, that he would have expected it to show up on his charts, so these charts are obviously updated on a regular basis.

 

But also "There are so many uncharted settlements." A rogue like Solo will have squirreled himself and his contraband away in plenty of the unregarded places across the galaxy and charted them for himself in case it becomes a useful place to return to or fly through. Hence the Falcon can calculate routes that shorten the distance from point A to B with confidence. Even in "uncharted" areas.

 

True, but then we must also remember that was in the Outer Rim when Ozzel said that. Alderaan is part of the core worlds and is a long ways away from the Outer Rim. Much closer to Courscant. Alderaan was part of both the Republic and the Empire compared to Hoth, which was in the Outer Rim like Tatooine and thus the governments don't really exist out there. Hence the uncharted settlements.

 

I am a bit surprised that ships dont seem to have any type of active sensor array that could alert the crew to a dangerous situation before droping out of light speed.
I have not seen a good in universe explaination of this other than than ships cant be tracked in hyperspace without some type of homming device being engaged.
I assume that there must be some type of interference that blocks sensors from reading the realspace environment around a ship while it is traveling at FTL speeds.

 

If the Earth's sun was the size of a grain of sand, then our solar system would be about the size of a shot put circle whilst the nearest star would be 7 miles away. So there's plenty of room to make the detection of other ships as potential collision targets not necessary. Space is well named!

 

While this is true for deep space once you enter a star system things get a bit more interesting. With Planets , moons , comets. asteroids . solar wind. dust , gravity wells etc much more complex calculations would be required. We know that the space shuttle and ISS have been hit by debris left over from earlier mission. Now add in hundreds of ships on differing flight paths and you get a very busy zone near planets.

 

I've been wondering if a ship on lightspeed could be traveling as a photon, so it wouldn't crash on anything. If that was the case, the ship and its interior would become another kind of thing, from matter to pure energy.

Or maybe the lightspeed would put the ship into a sort of tunnel, like a warp zone, running in parallel to the space time continuum. So it wouldn't crash on anything along the way.

On both cases, the only problem would be getting out of the lightspeed.

 

If that's so, why did Han say that hyperspace calculations had to be precise or they'd crash into a supernova or a black hole?

 

I think the stress of the Falcon jumping to lightspeed with a Rathar attached to it basically turned it into goo and it split apart. It's not as if the Falcon ran into it in the middle of a lightspeed jump, it started the jump and the transition to lightspeed is what killed it (and left the Falcon unharmed) because it was a biological mass on the outside of a ship and those can't survive the jump to hyperspace.

 

Well, there may be 2 situations for crashing:

1. While at light speed
2. Just after getting out of light speed

You cannot escape the gravity of a black hole, even at light speed. And you wouldn't want to end your journey near a black hole also.

 

Spoiler Alert
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Now it's canonical... It's possible for a ship to crash to other ships at light speed...
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End of spoiler.