Why didn't the Death Star jump to hyperspace to escape attack?

Question

In Rogue One,

we see the Death Star takes very little time to prepare and make a jump through hyperspace (from the time the battle of Scarif starts there is just a few minutes time that passes for Tarkin to move the Death Star into Scarif orbit).

Additionally, the Empire knew (or at least might have reasonably suspected) at this time that

the Rebels had in fact succeeded in stealing the plans of the Death Star from Scarif's data banks, and may have found a weakness in the design because of the treachery of Galen Erso.

That being the case, during the assault on the Death Star in A New Hope, why was the command not given to jump to hyperspace away from the attack?

Answer 1

At the end of A New Hope, the Empire is making an attempt to destroy the Rebel base on Yavin 4 and end the Rebellion once and for all, and going to hyperspace would prevent that. One officer does point out the risk to Tarkin, who dismisses his concerns:

Chief Bast: We've analyzed their attack, sir, and there is a danger. Should I have your ship standing by?

Tarkin: Evacuate? In our moment of triumph? I think you overestimate their chances.

So, the Death Star didn't jump to hyperspace because Tarkin and others in charge still didn't think the Rebel fighters were a threat, even once they figured out what the Rebels were trying to do in the trench. This is apparently due to a combination of doubt that the Rebels could successfully hit the small target, and overconfidence in the invincibility of the Death Star.

Why does Chief Bast suggest evacuation instead of retreat? We know from A New Hope that the Death Star was always supposed to be able to travel at interplanetary speeds at the very least, which is how it travels from Alderaan to the Yavin system, so this doesn't seem to be much of a retcon on Rogue One's part. In the quoted scene, Bast is speaking in a low tone even in private conversation, indicating that even a small-scale evacuation of high-ranking personnel would be embarrassing, so presumably a full retreat would be out of the question altogether.

Answer 2

There are several factors to consider here.

1. The optics of bringing a superweapon to the fight and then leaving. As previously mentioned, Tarkin, was unwilling to quietly slip out on his own-it's doubtful he would be ok with a full scale retreat considering what he was up against (enormous ball of death vs itty bitty starfighters).

2. The rebels chances. In order to be successful, the rebellion had to pilot it's way down the trench, fend off squadrons of TIE fighters, dodge turbolasers AND hit a small target while moving remarkably fast.

3. The Empire's intended endgame. Remember, the rebellion chose Yavin IV for a reason. They were able to hide their base there...in the jungle. I don't think it was ever outright stated on screen but I always got the idea that Tarkin and Vader planned to destroy the entire moon and not employ "single reactor mode." They wanted to make a statement to the entire galaxy and they couldn't do that with Star Destroyers.

4. Time was on their side. While moving the Death Star is probably cumbersome, it's clear that it can move rather quickly (for a moon sized space station). The rebels had to get the stolen plans, analyze them, find the weakness (which was probably not labelled doomsday device weak point), organize and launch an attack. Tarkin may have hoped to jump into the system on the heels of the Millennium Falcon and cut the rebels lead time significantly. Remember, Leia gave up the Yavin base BEFORE Luke and the gang were even on board so the navigators had practically the whole movie to plot a course.

Answer 3

Short answer, nobody knows if the Death Star can jump into hyperspace fast enough for it to be useful at the Battle of Yavin.

So if someone asks George Lucas why didn't the Death Star jump into hyperpspace he can always pretend that they thought about of it while making Star Wars but the Death Star takes hours to program and jump into hyperspace.

Of course the Death Star always had hyperdrive:

"Oh No!" "What is it?" "The Death Star has just entered our star system!" "What's the Death Star?" "The ultimate weapon of the First Galactic Empire. And it's headed for Alderaan!" "The First? Why, the Fourth Galactic Empire ended five Thousand years ago. What does some relic of the first one have to do with us?" "Did you sleep in your ancient history classes? Alderaan was the first planet to revolt against the First Galactic Empire, and now the Death Star has finally reached us after all those millennia."

Obviously the Death Star must have hyperdrive capability in order to be an effective weapon in a galactic civil war.

The only clue as to the Death Star's speed of jumping into hyperspace is Vader's statement.

"This day has seen the end of Kenobie and it will see the end of the rebellion."

If the entire hyperpace trip from Alderaan to Yavin takes less than a day, obviously preparing to and jumping into hyperspace takes less than a day for the Death Star.

But nobody knows how much shorter than a day is needed for the Death Star to prepare and jump. if there is a canon statement that it always takes X number of jumps into hyperspace to go from Alderaan to Yavin then the maximum time it could take the Death Star to prepare and jump would be 24 hours divided by X. And of course the Death Star might be able to jump into hyperspace much faster than that.

But nobody knows if the Death star can jump into hyperspace fast enough for it to be useful at the Battle of Yavin.

And were the rebel fighters far enough away that they would be left behind if the Death star made a short hyperspace jump or would they be carried with the Death Star?