Starkiller Base: A Star Wars (Economic) Story

Starkiller Base
Star Wars Episode VII: The Force Awakens, Starkiller Base, ©Lucasfilm LFL

In Star Wars Episode VII: The Force Awakens a new superweapon was unveiled. The so-called Starkiller Base was built into an ice planet. Based on its size and destructive capabilities, the costs for this fearsome base for the First Order could be astronomical. After all the much smaller sized Death Star cost the Galactic Empire on the order of $193 QUINTILLION ($193,000,000,000,000,000,000).1

Size of the Starkiller Base
Star Wars Episode VII: The Force Awakens, Starkiller Base and Death Star size comparison, ©Lucasfilm LFL

According to canon, the Starkiller Base has a diameter of 660km, which is verified by it having a diameter roughly 5.5 times that of the Death Star as depicted in Episode VII. As volume rises cubically with diameter, a first pass analysis would state that the Starkiller Base costs: $20.221 SEXTILLION ($20,221,000,000,000,000,000,000).2

However, though the Death Star was constructed from nothing, the Starkiller Base has an entire planet as its foundation. As such, calculating the costs of the Starkiller Base based on planetary volume is not appropriate. Instead, the excavation of the equatorial trench (wrapping around roughly 50% of the planet) would be the majority of the construction. This trench has an approximate depth of 10% of the radius (33km) and width of approximately 25% of the radius (82.5km). Thus the excavated volume is approximately 2,680,000km3. This leads to a cost of approximately $360 QUINTILLION, which is still significantly more expensive than the Death Star.3

The obvious first thought is whether the Starkiller Base would require additional costs as its weapon is able to destroy the entire Hosnian system from a great distance whereas both Death Stars required close proximity to the target and could only destroy one planet per shot. Ultimately this cost is kept comparable as the energy required is collected utilizing the resources provided by a nearby star. Holding onto the energy though should require further resources as the star is absorbed and stored before the weapon is used. To consider this, let us consider the geological makeup of the planet itself. With a diameter of 660km, the volume is 150,532,554 km3. Additionally, given the behavior of our heroes and villains on the surface of the Starkiller Base, there must be Earth-like gravity. Using Newton’s laws of universal gravity, the mass must be approximately 1.6 × 1022 kg.4 Thus the density of the Starkiller Base planet is roughly 106,338 kg/m3. This is just under 5 times the density of osmium, the densest naturally occurring element known to humans, and over 13 times the density of steel. With such high density it is likely this small planet was chosen specifically by the First Order for its ability to store dark energy. As such we can assume that costs are in line with size of the weapon system.

If, however, the planet were able to support life through its natural atmosphere, the costs would be reduced to approximately 2.59% of the total cost.5 That is, if the planet that the Starkiller Base was built into was able to sustain life, its total cost would be a mere $9.315 QUINTILLION or just 4.83% of the cost of the Death Star.

To determine the ability of the Starkiller Base to naturally support life, we need to determine its atmospheric conditions. Reportedly, the atmosphere is breathable, which indicates an Earth-like atmosphere of primarily nitrogen (N2) and oxygen (O2). For completeness we will also consider the average molecule in Earth’s atmosphere (dry air). In a galaxy with interstellar travel and the ability to terraform a planet these may need to be replenished and thus not reduce the costs. So the big question is surrounding the atmospheric escape on the Starkiller Base. This follows rules based on the Maxwell-Boltzmann distribution. In particular, we are interested in the probability that the atmosphere escapes naturally through molecules exceeding the escape velocity. Due to the size and mass of the Starkiller Base, we determine its escape velocity to be approximately 2544 m/s.6 With the Starkiller Base being built on an ice planet, but Rey, Finn, and Kylo Ren all seemingly comfortable on the surface, the temperature is seemingly near 0°C (or 273.15K).

Rey and Kylo Ren
Star Wars Episode VII: The Force Awakens, Battle on Starkiller Base, ©Lucasfilm LFL
Thus with molecular weight of 28 amu for N2, 32 amu for O2, and 29 amu for dry air, we conclude that the probability of molecular escape is so close to 0 to be negligible. Thus without the need for continuous injections of air into the atmosphere, the planet is self-sustaining.7

The only remaining concern is the atmospheric pressure at the bottom of the Starkiller Base trench. With the assumption that the pressure at the surface is 1 atm (i.e., comparable to Earth at sea level), which is implicit in the assumption that the atmosphere is sufficient to support life, then the pressure at the bottom of the trench is 62.3 atm. As 10 meters of depth in water corresponds to approximately 1 atm of pressure, this is about equivalent to a submarine at 623 meters. At this depth, modern American Seawolf class submarines are designed to operate. Since the Starkiller Base will primarily be constructed from the planet itself, the dense natural material (106,338 kg/m3) would act as the hull on a submarine keeping the humans safe.

TL;DR: The Starkiller Base costs $9.315 QUINTILLION or 4.83% of the cost of the first Death Star.

1. Assuming a diameter of 140km for the first Death Star. This has since been retconned to anywhere from 120km to 160km.
2. Starkiller Base cost = Death Star cost × (Starkiller Base volume / Death Star volume) = $193 QUINTILLION × (330/70)^3 = $20.221 SEXTILLION.
3. Excavation may be cheaper, especially as the extracted minerals can be sold for profit.
4. Newton’s laws state that planetary mass is equal to the square of planetary radius (330 km) multiplied by the acceleration due to gravity (9.81 m/s2) and divided by the universal gravitational constant.
5. It costs roughly 38.67 times more (pound for pound) to send a living human than lifeless cargo. The original cost computations assumed an artificial atmosphere would be required to keep humans alive, without that we can divide the cost for the Starkiller Base by 38.67.
6. Escape velocity is the square root of twice the multiplication of the acceleration due to gravity (9.81 m/s2) and planetary radius (330 km).
7. Water vapor would escape the atmosphere at a slow rate, but as must water would remain as ice on such a planet, this can be neglected without concern.

Rogue One and Building the Death Star

Building the Death Star
Rogue One: A Star Wars Story, Death Star, Ph: Film Frame, ©Lucasfilm LFL

With Rogue One officially coming out tomorrow, I wanted to revisit my paper from a year ago: It’s a Trap: Emperor Palpatine’s Poison Pill. Specifically, since this takes place before Episode IV, I want to look again at the costs associated with building the first Death Star and how that was used to calibrate the size of the Galactic Economy.

To deduce the costs of the Death Star being built in Rogue One, the first Death Star, I began by looking at the petition to the White House in which an estimated cost of over $850 QUADRILLION was given for building such a moon-sized battle station. However, going back through the sources, this value is only for the raw materials. Scaling up the cost from raw materials to the full cost changed that estimate by a few orders of magnitude, all the way to $193 QUINTILLION (that’s 193 followed by 18 zeros).

As evidenced by the discussions taking place in the trailers for Rogue One, the building of the first Death Star was a massive military research and develop project. Thus to use the cost of the Death Star to find the size of the Galactic Economy, I looked at history to find comparable projects. Ultimately I settled on a comparison to the Manhattan Project (building the first atomic bomb). That project cost 0.21% of US GDP per year from 1942-1946. As such, assuming the same cost profile, the Death Star’s $193 QUINTILLION would be 0.21% of the GGP [Gross Galactic Product] over its 20 year construction time. This leads to an estimated $4.6 SEXTILLION (21 zeros) in GGP per year on average. Sure makes the costs seem much smaller, though still big enough to damage the Galactic financial system.

We’ll just have to see if Rogue One has scenes in which Emperor Palpatine, Darth Vader, and Grand Moff Tarkin fret over the galactic finances in building this moon-sized battle station.

Thoughts on the Operational Costs of the Death Star

The cost of the Death Star is near and dear to my heart. Recently OVO Energy has worked on calculating the operational costs of running the Death Star for a single day. The majority of these costs will come in the form of the energy required to use the weaponry and jump to hyperspace. That is, the cost with current Earth technology to produce the requisite power output.

However, the power output is a function of technology and not just raw materials. The mere presence of regular hyperspace travel proves that a new energy source is available at extremely low cost. Thus while the 1032J of energy required for the Death Star’s laser would cost approximately £4.1666667×1024 using current Earth technology, it would be a significantly smaller fraction of the Galactic economy to produce. Consider that the Millennium Falcon is a “piece of junk” and was abandoned on Jakku without being sold for parts, but it is still capable of hyperspace travel. This fact proves that energy costs are no longer the limiting factor and a much smaller fraction of the economy.

That being said: Excited for Rogue One to come out!

Estimates of the Operational Costs for running the Death Star. Credit OVO Energy.

Blog at

Up ↑