Is the Death Star Big Enough to Create Its Own Gravity?

Friday, 04 November 2016 - 2:15PM
Science of Star Wars
Astrophysics
Friday, 04 November 2016 - 2:15PM
Is the Death Star Big Enough to Create Its Own Gravity?
If you didn't make it to Outer Places' panel on the science of Star Wars this year at Comic-Con, here's the next best thing: a video on the physics of the Death Star. Besides being the ultimate power in the galaxy (at least according to Admiral Motti), the Death Star is gigantic in size—though whether it can be classified as a "small moon" is a topic of debate. Either way, there's one big issue with its day-to-day operations: the problem of gravity.

Is the Death Star large enough (or dense enough) to create a gravitational pull that keeps all the Stormtroopers and Imperial officers with two feet on the ground? According to Kyle Hill, host of "Because Science," it's a bit more complicated than that.



So, in conclusion: no, the Death Star's mass is not great enough to create enough gravity to pull everyone down to the floors naturally. Instead, Hill hypothesizes, the station creates artificial gravity by spinning multiple, nested spheres inside of itself to create centrifugal force. But, as the comments in the video point out, even that's not a perfect solution. As Kyle himself admits:

Opening quote
Hey so I think I screwed this up a bit not being clear on my design. Many of you are right: the gravities that I calculated really only work at a right angle to the axis of rotation, so most of the workable gravity in my design would be at and around the equator — imagine large, concentric "ring worlds" on the interior — with gravity getting smaller and weirder (not pointing to your "down") as you move towards the top and bottom. I know there wouldn't be gravity at the center axis, and I think that's fine overall. My design also doesn't work great with windows and shafts and docking bays as shown in the canon, unless you shift those around to face "upwards." I really hate when I don't think of stuff that you all do: I'm just one guy writing these by myself, so that's on me as an educator, and I apologize if my theory doesn't check out with y'all. Thanks for keeping me honest. — KH
Closing quote


There's one other problem: there's already a complete technical manual for the Death Star, licensed and approved by Lucasfilm, and it doesn't seem to mesh with Hill's hypothesized Death Star design, which relies on those spinning internal rings:

Death Star Workshop Manual


So what is causing all that gravity? Well, artificial gravity generators. Besides being the universe of infinite fuel, Star Wars is pretty liberal about anti-gravity, too. It's on the Tantive IVThe Millennium Falcon, and just about any other large spaceship, judging by the fact that the characters aren't floating around. Still, it's interesting to try and figure out how you would pull it off if, say, Elon Musk were to convert the Moon into a giant laser weapon.
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