It's one of the most iconic sequences in all of film. The evil galactic empire takes the
captured princess to her home planet, a world not too different from Earth, threatening
to destroy it. I want you to think about this for a second. A battle station about a quarter the size of
the moon with an unexplained power source, fires a laser beam at a planet the size of
earth and completely destroys it. Not only doe the death star completely destroy Alderaan
from the force of its blast, it does so in a matter of seconds and kicks of at least
a substantial part of the planet into space. From a physics point of view, how much energy
and power would it actually take to cause this level of destruction, and what kind of
physical possibilities are there out there to actually accomplish it?
First off let's consider the planet Earth and the force binding it together. As Obi-Wan
famously said, "It surrounds us and it penetrates us. It binds the galaxy together." But the
force binding the Earth together isn't the mysterious one from the Star Wars Universe,
it's simply gravitation. And the gravitational binding energy of the planet, which is the
minimum amount of energy we would have to put into it to blast it apart, is an astonishing
224 million septillion joules. To put that into perspective, it would take a full weeks
worth of the Sun's energy output, delivered to an entire planet in a matter of a few seconds
to cause that type of reaction. Remember what actually happens inside a Sun like star? Hydrogen
is burned via the process of nuclear fusion into heavier isotopes and elements resulting
in helium. Each second in the Sun, 4.3 billion kilograms of matter is converted into pure
energy, which is the source of the Sun's energy output. Let's imagine that's exactly what
the death star is doing.
We could simple have the death star fire a beam of light into the planet. This would
be catastrophically inefficient however. Imagine a solid material structure, even one as big
as our moon, trying to generate and expel this much energy in a matter of a few seconds.
Releasing that much energy in one direction would cause a moon mass object to accelerate
in the opposite direction to a speed of 78 kilometers per second from rest. Something
that clear didn't happen when the death star was fired. In fact, there was no discernible
recoil at all.
But there is another way this planetary destruction could have happens and it's based on one assumption.
Princess Leia is made up of matter. Since shes made up of matter and grew up on Alderaan,
we can assume Alderaan is made up of matter as well. Meaning if the death star fired pure
anti-matter, it would only need to supply half the total energy since the target would
supply the other half. If this was the case, only 1.24 trillion tonnes of anti-matter would
be suffice to provide the minimum amount of energy need to blast that world apart. In
the grand scheme of things, that's not so big. For example, an anti-matter asteroid
with the same density of Earth would only need to have a diameter of about 7.53 kilometers
to do the job.
It's not completely inconceivable to think that a we could collect this much anti-matter.
We've been able to create neutral anti-matter and store it successfully for reasonable long
periods of time, long enough that it is only our failure to keep normal matter away from
it that causes it to annihilate in such short order. It's not unreasonable that an advanced
technological civilization, one that's mastered hyper drive and faster than light travel,
could harness, say, the energy from an uninhabited star and use it to produce neutral anti-matter.
The way we do it on Earth is we collide one proton with another proton at high energy
and speeds. What you get is are three protons, and one anti-proton. That anti-proton combines
with a positron to produce a neutral anti-hydrogen.
In the interiors of gas giants like Jupiter and Saturn, the incredibly thick hydrogen
atmosphere extends down for tens of thousands of kilometers. Whereas the pressure at Earth’s
atmosphere is around 100,000 Pascals, at pressures of tens of Giga-pascals, hydrogen can enter
a metallic phase, something that should no doubt happen in the interiors of gas giant
planets.
If we could achieve this state of matter, we could use hydrogen as a conductor. It's
believed that that is what's responsible for Jupiter's intense magnetic field . All the
laws of physics suggest that if this is how matter behaves, and we can do this with hydrogen,
then this must also be how antimatter — and hence, antihydrogen — behaves, too.
So all it would take, if you want to destroy about the size of Earth, is a little over
a trillion tonnes of metallic antihydrogen, and to transport it down to the planet’s
surface. And as matter-and-antimatter annihilate according
to E=mc^2, the result is the release of pure energy
Anyways, guys, I hope you enjoyed this video. This was just a quick look at exactly how
the death star could possibly be implemented in our universe. This video was actually written
by Ethan Siegel. He's a fantastic writer. This was actually a blog post over at his
website, you can check that out as well as his book and his Patreion. Again, those will
be linked in the description below. Anyways guys, if you were in charge of the death star,
would you use it for good or would you use it for evil. Let me know in the comments down
below. Anyways guys, leave the video a like and be sure to set notifications to on. Anyways
guys, thanks for watching.