SPOILER ALERT. I'm going to talk about Star Wars: The Force Awakens. If you haven't seen it by now, I have a feeling that you either don't really care about the movie or you don't care about spoilers. But don't worry, I'm not going to give away anything major. Still---you have been warned.
In one scene in the movie, Han Solo and Finn (oh, and Chewbacca too) are trying to get on the surface of the Star Killer to disable the shields. Here is the important dialogue as they approach the planet.
Shortly after, Han says "OK Chewie, get ready...and now!" Then Han pulls a lever (mostly likely to come out of light speed) and I'm not sure what Chewie does. Now, if Han Solo is flying the Millennium Falcon at light speed, and he wants to stop the starship inside the shield (but not inside the planet), how large of a time window would he have to react?
Of course I am going to start with a picture. This is the Starkiller Base and the shield (not drawn to scale).
In order to get the maximum below-shield flight path length, I need two things. First, the radius of the Starkiller base. I will just assume this is Earth-sized with a radius of 6.4 x 106 meters. Second, I need the radius of the shield-sphere. I am going to say this is about the height of "space" for Earth which is defined to be 100 km above the surface. This would give an R value (from the diagram) of 6.5 x 106 m. Putting these values in to the chord equation I get a maximum flight distance of 2.7 x 106 meters.
No one really cares about the distance you can travel. What matters is the time. If the Millennium Falcon is traveling at light speed, how long would it take to pass through this zone?
A time of 0.009 seconds (let's just say 0.01 seconds) is a really short time interval. But is it too short? OK, let's suppose that it is only Han that has to react to this time window---it doesn't really matter what Chewie does. It seems that a fast human reaction time might be around 0.1 seconds. That's too slow for this window. With that reaction, Han might come out of light speed after he has already passed back through the shields. However, I think that reaction time is for something unexpected. If you know it's coming up, you might be able to react faster. I'm going to say this maneuver is plausible. After all, Han is an expert pilot.
But what if this drop out of light speed requires some action from Chewie? In that case, several things need to happen. It might go something like this (I have included estimated times for each step).
- Han reacts to reaching the shield. Let's say he can do this in 0.01 seconds (because he's Han).
- Han says "Now!" Totally guessing this would take 0.1 seconds.
- The sound travels from Han to Chewie. With a speed of sound at 343 m/s and a distance of 1 meter, this would be 0.003 seconds.
- Chewie reacts. I guess he's at least as fast as Han---so 0.01 seconds.
For this second case, the total reaction time could be up to 0.123 seconds. That's too long. They wouldn't make it. But maybe Chewie doesn't really do anything. Maybe Han yells "Now" just to scare the crap out of Finn. Maybe.
