Death Stars are a waste of time – here's the best way to take over the galaxy

December 22, 2015 by Stuart Armstrong, The Conversation

The Star Wars films raise lots of pressing questions. "Why is there sound in space?" "How did George Lucas lose his way?" And, of course, "Did Han shoot first?" (that's an easy one).

There are innumerable variants on the "How realistic is Star Wars?" question. The answer is, of course, not very. But it's fascinating to use this question to probe what space combat might really be like.

For example, several people have tried to answer "How to build a Death Star?", referring to the first film's moon-sized space station with the power to destroy a planet. A less obvious but perhaps more important question is "If robots like R2-D2 exist in the Star Wars universe, why are the bad guys' superweapons so big in the first place?"

The presence of R2-D2 and other robots tells us something very important about the "Galaxy far, far away". Namely, that they have access to a workforce that can be churned out in large numbers and copied as needed. If you have robots with skills somewhat comparable to humans, you have access to recursive manufacturing: manufacturing that builds upon previous manufacturing. You can thus build a factory, that can build robots, that can build another factory, that can build robots, and so on, going on until all the and energy of the planet (or star system) are used up.

Even if robots aren't very good builders, this kind of exponential growth means that robot-powered recursive manufacturing will rapidly overwhelm and surpass more conventional manufacturing, and grow ever faster. In the Star Wars universe, the majority of the physical production should come from such recursive manufacturing.

Starkiller Base

In the latest Star Wars film, The Force Awakens, the evil First Order have created a weapon even bigger than the Death Star. Known as "Starkiller Base", it is constructed from an apparently hollowed-out planet and can suck all the energy from a nearby star before using it to fire destructive beams at multiple planets at once.

Death Stars are a waste of time – here's the best way to take over the galaxy
Today’s forecast: planet-detroying energy beams. Credit: Lucasfilm

As far-fetched as this sounds, constructing such a large structure around or in a planet would be relatively easy with recursive manufacturing. With a vast army of builders at your command, your only effective limitations are the amount of raw materials (mostly the planet itself and any others nearby) and your energy source (most likely the nearest star).

The problem is that this isn't a very efficient way of building a weaponised force for wiping out multiple planets. Instead of constructing one base made up of trillions of tons of metal and rocks, why not construct lots of them, each just a shell and a weapon, run by robots? You'd have completed half a million lightweight superweapons in the time it would take to build one massive one. Even if the robots aren't particularly good at their jobs, the redundancy of having so many would overcome this.

The next question is whether these weapons could really destroy a planet? That would require, at the very minimum, breaking the planet into fragments that go on their separate and unmerry ways. This means that you have to overcome the gravitational of the planet, the total gravitational force that keeps the planet together.

The gravitational binding energy of the moon is around 1.25×1029 Joules. That's the minimal energy requirement for completely blowing it up. In practice, however, you'd need more. That energy is about six minutes' worth of our sun's output, so it seems feasible that destroying the moon could be done.

But planets have higher binding energies. Large gaseous planets like Jupiter have binding energies of around 2.04×1036 Joules. That would require about 170 years' worth of the sun's energy – far less plausible, although maybe possible if you could really drain an entire star. But if you're draining a star, you have to overcome the star's own binding energy first, requiring even more energy to start with.

Death rays

A much more efficient way to defeat multiple civilisations would be to hit all the planets with a large mass at high speed – rather than an energy beam – enough to shake the big ones with immense tremors, and crack the crusts of the small ones, making them unlivable. You could then saturate them with enough ionising radiation to fry all electronics and kill any surviving living organisms. That would be much more economical from the bad guys' point of view.

But that's still a waste of . Using recursive manufacturing, a much simpler idea is to seed space with factories churning out other factories (of course), detection systems, and intelligent missiles. Within a few years, such factories will have transformed most of the nearby asteroids and planets into missiles.

The process will have almost certainly uncovered any rebels trying to hide nearby, and dropped a few (billion) missiles on their heads. And the same happens for any new enemies trying to set up in the system later. With these self-replicating weapons, once you've hit a star system, it stays yours. Even if someone else tries the same approach, their initial factory will be easily discovered and destroyed.

So, the existence of R2-D2 implies that the real superweapons shouldn't be the flashy Death Stars and Starkillers, but the simple mobile robotic factory, that can be dropped discreetly into myriads of star systems to rapidly and permanently take them over.

Explore further: Could a 'Death Star' really destroy a planet?

Related Stories

Monster planet is 'dancing with the stars'

December 16, 2015

A team made up almost entirely of current and former Carnegie scientists has discovered a highly unusual planetary system comprised of a Sun-like star, a dwarf star, and an enormous planet sandwiched in between.

Recommended for you

Milky way had a blowout bash six million years ago

August 29, 2016

The center of the Milky Way galaxy is currently a quiet place where a supermassive black hole slumbers, only occasionally slurping small sips of hydrogen gas. But it wasn't always this way. A new study shows that 6 million ...

Hubble spots an irregular island in a sea of space

August 29, 2016

This image, courtesy of the NASA/ESA Hubble Space Telescope's Advanced Camera for Surveys (ACS), captures the glow of distant stars within NGC 5264, a dwarf galaxy located just over 15 million light-years away in the constellation ...

NASA's Juno successfully completes Jupiter flyby

August 29, 2016

NASA's Juno mission successfully executed its first of 36 orbital flybys of Jupiter today. The time of closest approach with the gas-giant world was 6:44 a.m. PDT (9:44 a.m. EDT, 13:44 UTC) when Juno passed about 2,600 miles ...

5 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

antialias_physorg
5 / 5 (5) Dec 22, 2015
Within a few years, such factories will have transformed most of the nearby asteroids and planets into missiles.

Weeell, the obvious flaw in a stock of (possibly decentralized) attack weapons manned by robots is that a single set of computer virus could shut them down (or turn them against you)...pretty much what heppened with the storm troopers IIRC.

So going for one big weapon under central control might be a better bet (and in the end Star Wars isn't SciFi, but SciFantasy...so it's more of an Adolf Hitler/Albert Speer analog WRT having brutalist/massive buildings centered around single individuals and their egos rather than being optimally efficient at subjugating stuff)
joespahr
5 / 5 (1) Dec 22, 2015
Read "Existence" by Dr. David Brin.
Whydening Gyre
5 / 5 (2) Dec 22, 2015
Within a few years, such factories will have transformed most of the nearby asteroids and planets into missiles.

Weeell, the obvious flaw in a stock of (possibly decentralized) attack weapons manned by robots is that a single set of computer virus could shut them down (or turn them against you)...pretty much what heppened with the storm troopers IIRC.

It's what us humans did to the alien invasion force in "Independence Day"
Which, BTW, I can't hardly imagine a sequel to...:-)

So going for one big weapon under central control might be a better bet (and in the end Star Wars isn't SciFi, but SciFantasy...so it's more of an Adolf Hitler/Albert Speer analog WRT having brutalist/massive buildings centered around single individuals and their egos rather than being optimally efficient at subjugating stuff)

Egads - Military Industrial Complex run amuck...
syndicate_51
5 / 5 (1) Dec 23, 2015
Simply put, the denizens of the Star Wars universe have had to deal with Droid revolution before so everybody is afraid to build this. It's why droids get their memory banks wiped periodically.

People believe it or not in general in that galaxy are somewhat more wary of AI than most sci-fi fantasy settings.
TheGhostofOtto1923
3 / 5 (2) Dec 27, 2015
Nah the best way I've seen to destroy a planet is the one proposed by greg bear in forge of god. The demolitionists send a lump of degenerate matter into orbit around the planets core, and a lump of degenerate antimatter orbiting in the opposite direction.

As their orbits decay the planet slowly turns into plasma.

Of course it would take a recursive tech to create that much degenerate stuff, which the author also suggested.

BTW humans got revenge by simply turning the core of the enemy's planet into antimatter using borrowed tech.

But of course that's just silly.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.