That's no moon.
It's a space station.
The enormous, planet-killing kind,
designed for only one thing —
to bring order to the galaxy.
It's Star Wars' Imperial superweapon,
the Death Star.
I've got a bad feeling about this.
But it took the Empire 19 years
to build their first Death Star,
so we'd better get started.
It's unclear exactly how big
the DS-1 Orbital Battle Station was.
Estimates vary between 120 km (75 miles)
and 160 km (99.5 miles) in diameter.
That's substantially smaller than our Moon.
But compared to some of the smallest
moons in the Solar System,
it's enormous.
And we'd only need one thing to build it.
Big projects cost big money.
In this case, we're talking $852 quadrillion.
Eight hundred and fifty-two with 15 zeros.
And that's only the cost of construction.
Once the Death Star is ready,
keeping it up and running wouldn't be any cheaper.
Weapon or not, this space station
would require 1.7 million staff
to run the station's retail shops and
troop cafeterias.
Add 25,984 stormtroopers
and 342,953 Imperial Navy soldiers,
and you'll get 2,068,937 people
living aboard the Death Star.
If each person on the Death Star
created 1.13 kg (2.5 lb) of waste every day,
it would cost $564,925 daily
not to turn the Death Star into a landfill.
That doesn't include people who fell into a trash compactor
and weren't able to blast their way out.
"Come in 3PO!"
The daily electricity bill
would add up to $52 billion.
$274,000 to feed the crew,
with another $20,400 to supply tea or coffee.
$233,000 for one cycle of laundry.
You wouldn't expect your troopers
to run around with dirty underwear, right?
The total for keeping the Death Star operational
would amount to $7.8 octillion —
That's more money than we currently have here on Earth.
And it doesn't include the cost
of a single blast of superlaser.
That would be an additional $8 octillion.
Still feel like firing lasers into planets?
Okay, then let's talk about
how you could build the Death Star.
You already know it would come
with the price tag of $852 quadrillion, but...
First, you'd need a hypermatter reactor core.
Let's not go into the specifics
of how such reactor would work,
and we'll just assume you already have one.
You'd build four reactor shafts,
all joined along the equator,
and a large column running from top to bottom.
This column would help to distribute power
and also act as a station stabilizer.
This mega project would require a lot of steel.
By some calculations,
the Earth has enough iron in its core
to provide for two million Death Stars.
But you wouldn't want to sacrifice our planet
for an army of deadly weapons, would you?
Even if you took only the amount of iron
needed for one Death Star,
it would take over 830,000 years
to produce enough steel
so you could begin construction.
And it would take millions of rocket launches
to get the steel where it needed to go.
By the time the Death Star was finished,
this might make the atmosphere so polluted
that we'd be forced to move away
from Earth to another planet.
We can't get too far from our planet, but...
you definitely don't want that thing
in Earth's low orbit.
There's too much of a chance of it
falling down to Earth.
You could start building
outside of the Earth's atmosphere.
Just make sure to not accidentally
blast our planet with the superlaser.
Speaking of the blast...
In reality, light doesn't behave that way.
Instead, it would keep moving
in whatever direction it was fired.
"Sorry about the mess."
By the way, destroying an Earth-sized planet
would require a lot of power.
You'd need to spend a week collecting
all of the Sun's energy
before you could fire up the Death Star.
And don't stand anywhere close to the beam
at the moment of the blast.
So much energy right next to you,
even when not aimed directly at you,
would cause you to evaporate
in a matter of seconds.
Then there's the recoil.
The third law of motion teaches us that
every action has an equal and opposite reaction.
That means if you packed a big enough punch
to destroy a planet using the Sun's energy,
it would send the Death Star in the opposite direction
at a speed of 77 km (48 miles) per second.
That's unless you had an antimatter device
aboard the Death Star.
Antimatter is matter, but
with its electrical charge reversed.
When antimatter meets matter,
the two destroy one another.
That's why you'd only need 0.00000002%
of a targeted planet’s mass in antimatter
to turn that planet into space debris.
In this case, the recoil would be almost unnoticeable.
But you'd better not aim the Death Star
at any planets in the Solar System.
There is a better application for this weapon.
It could be used to vaporize any asteroids
that could be a risk for our planet.
Although a giant death orb might be
a little overqualified for the task.
At least when an interstellar asteroid
is hurtling in our direction,
we'd be ready to knock it out
before it destroys us.
"I've got a bad feeling about..."
"Quiet".
Building the Death Star would be
a very long and very expensive process.
Do. Or do not.
There is no try.
But maybe spare the Earth for now,
and save the deadliest weapon in the galaxy
for some angry aliens that might
come to visit us one day.
But that's a story for another WHAT IF.