There are plenty of concepts in Star Wars that just straight up require a suspension of scientific understanding. Some of the classic are: no sound in space, explosive fireballs in space, and the basic laws of gravity. However; all of these blights allow for a more entertaining movie so we allow them without much questioning.
Also…why does every spaceship in Star Wars always orientate itself to be right-side up? There is no right side up in space!
The first scene of “The Last Jedi” starts out with an iconic space battle. Poe Dameron and Leia Skywalker are leading a bombing run on a First Order “Dreadnaught” star ship. In Hollywood, we like loud explosions, but does the science check out?
Well we should all remember that, in space, no one can hear you scream. This is because sound essentially is just fluctuations in pressure that our ears detect. These fluctuations need to have a medium to propagate and in space there is no such medium. On earth, we have an atmosphere and bodies of water to act as that medium, but the vacuum of space is much more void.
Hence, space battles would be eerily quiet expect for the sounds echoing in the contained atmospheres of your ship. Imagine firing a guided missile into the hull of the other ship and hearing nothing after the release. In the distance, you would see the weapon make impact, but nothing but dead silence would ring in your ears (and probably some beeping controls from your monitors.)
Yes, bombs work in space, but they are much less effective. Most of the destruction from an incendiary bomb on Earth requires an oxygen rich atmosphere to cause a fireball and that same atmospheric medium to cause a devastating shockwave.
But lets not overlook the great minds of the Star Wars arms dealers on Canto Bight. If they did design a bomb to have similar destruction to what we see in the movies (like those released by the Y-Wings onto the Dreadnaught), they would require all the reactants and fuel for the explosion to be included in the payload. Perhaps these bombs were designed to contain pressurized oxygen or some other gas to account for the fireball and have large amounts of schrapnel to penetrate the hull of the ship.
Or even better, these bombs could be designed to penetrate the hull of the enemy ship and then explode from within using the air of the ship as a medium for both the explosion and the shockwave.
To imagine more future tech explosives, if they were instead nuclear bombs, then they would have a lot of destructive power from their radioactive eminence. But still, nuclear bombs also attribute a large portion of their destructive power to a shockwave through the atmosphere.
Below is an image of a Tie Fighter exploding in a ball of fire in “The Last Jedi.” The only way for this sort of explosion to occur is for their to be a large amount of oxygen in the cockpit or the components of the ship are very unstable and incendiary.
However, in this next image from “The Force Awakens,” a Tie Fighter is destroyed with much more of a realistic visual effect, but, ironically, it is in the atmosphere of Jaku. Im guessing the backdrop of space would make this shot less impressive?
In both of these shots, a ship is exploded using plasma cannons fired from a ship. While the tech is a bit more advanced, the idea behind it is the same as any onboard gun in todays fighter jets.
In the military, we call them Kinetic weapons, and they range from the musket to the new tech railgun. They are essentially any sort of device that fires projectiles at a high rate of speed intended to tear apart whatever it hits; the more momentum, the more destruction. With enough momentum, a kinetic weapon could have the destructive power of a nuclear weapon, but without any of the radioactive side effects.
Many people might believe that the blasters and cannons in Star Wars are laser weapons, but they are in fact kinetic weapons that fire plasma projectiles according to the Star Wars cannon.
Plasma, itself, is the fourth state of matter, and while it may not be very familiar to most common folk, it is actually the most abundant form of matter in the universe. It is what you are looking every time you glance out the stars, it is in every flash of lightening, and every fluorescent lightbulb. In scientific terms, it is an excited state of matter in which electrons are stripped from their nuclei and freely wander. This state of matter is complicated to work with because it is extremely hot. For example, the interior of the Sun is thought to be around 15 million degrees K; however, plasma has been generated in lab environments on the scale of thousands of degrees K. When generating plasma in the lab, one must contain a compressed gas inside of some sort of shielded container (usually electromagnetically contained) and excite it with energy in the form of heat until it turns to plasma. THis is pretty much how Star Wars described their weapons and this type of plasma is certainly hot enough to ignite any oxygen in a Tie-Fighter or any other flammable materials but probably not on the scales we see in the movies.
One of the most powerful scenes in the movie is when the Rebel lead ship jumps to light speed in a crash course with the First Order command ship. Essentially, in this moment the rebel ship itself becomes a projectile, just like a cannon ball or bullet, with a momentum equal to its mass times the speed of light. Thats a lot of momentum! The destruction caused by this ship proves that a kinetic weapon still could be the most effective in this universe.
Due to the power of this type of weapon, the United Stares military actually has a program, named “Thor” or “Rods from Gods.” This program explored the potential of a massive kinetic weapon being fired from a satellite. The science behind it was staggering, reigning down metal rods from the sky onto enemy installments could be immensely devastating. The incentive for this type of weapon was also inspired by international sanctions that prevent chemical, biological, or nuclear weapons to be fired from space. It was a interesting venture, but eventually the government gave up on this type of weapon due to the cost of rocketing heavy tungsten projectiles to space. A conventional intercontinental ballistic missile would still be much more cost efficient.
It is strange to think that in a world of light speed and the force, perhaps a kinetic weapon is the most deadly of threats. However, what we know about lasers is that they are very difficult to focus over large distances. Some weapons like the Death Star are thought to be giant lasers; however, Star Wars employs the help of the mythical and magical Kyber crystal to allow for their focused strength. In fact, the kyber crystal is used for many gaps in scientific knowledge like powering the iconic lightsaber.
The lightsaber is described by lore to be a plasma weapon as well, which makes holding it a very daunting task unless there is some sort of force field protecting the Jedi or Sith from being burned by temperatures reaching the tens of thousands degrees K. In fact, this type of force field would most certainly be required to fix a few of the conceptual issues with a light saber.
Plasma in its natural state does not stay contained easily, and so the lightsaber has been said to be contained using a magnetic field. In the lab they use electromagnetic barriers to prevent plasma from lighting the whole place on fire, but in our laboratories it would require 360degree containment. In the Galaxy far far away, we only have the handle to generate some sort of field.
This leads many hypothesizers to believe that the light saber is actually a plasma loop following a very sharp magnetic field line looping out from the source. This may seem like a good answer, and may even account for the reflection of blaster fire. But this type of technology would prevent the one thing that we love the most about lightsabers, the lightsaber duel. Two magnetically charged, plasma sabers would interfere with each other causing the loops to become uncontrollable. Instead of reflecting against each other, they would cause the plasma to shoot off in unpredictable patterns and kill everyone involved.
In order to control this plasma and also have some sort of solid aspect to the lightsaber, it seems that there would need to be some sort of rod that extends from the handle. This rod would have to be able to both withstand very high temperatures and conduct a magnetic field. As of now, we do not have any such material that can do both, but perhaps one day we will; materials like carbon nanotubes and ceramics are the most promising as of now.
End of the day, these strange weapons are what keep us in wonder about the world of Star Wars, and the stories themselves revere the lightsaber as more magical than scientific. Perhaps one day we will be able to create a lightsaber, or perhaps we will create something much more powerful.
The last scientific theme of “The Last Jedi” I wanted to address is the effects of the vacuum of space on a unprotected human body. When Leia was jettisoned into space after the bridge was destroyed, many people in the theatre and afterwards complained that she would definitely not have been able to survive the vacuum of space for that long. However, even without the help of the force, it is possible for the human body to withstand short exposures to space.
Most estimates for how long the body can survive space is just a few minutes but you would lose consciousness within the first 15 seconds. This is because the first rule of surviving the vacuum of space is to exhale as much as possible. If you do not exhale, the air in your lungs will rapidly expand and your lungs will rupture along with many other internal organs. In “The Last Jedi,” we see Leia’s skin begin to freeze as the moisture on her hands solidify, but in actuality, it is the evaporating of liquid from the surface of your body that causes you to feel some cold sensation. In fact, one accident at NASA in 1965 led to a worker to be exposed to a vacuum for a few seconds. He was eventually revived and mentioned that the last thing he remembered was the saliva on his tongue slowly beginning to boil.
The idea of freezing or burning up in space is a difficult one to understand. In order to have heat or cold you need a medium to allow for the transfer of temperature between mediums. In space, there is nothing really there to transfer energy to, so you wouldn’t burn up or freeze. The ice crystals forming on Leia as she drifts through space is a stunning effect, but not at all accurate. In fact, space is actually considered to be a good insulator. It is instead the drop in pressure that causes the evaporation of the bodies liquids and expansion of the air in your lungs. Literally all the air in your body would rush out in the first few seconds leaving you unconscious. However, there is enough internal pressure from the elasticity of your veins and arteries and the pumping of blood from your heart, that your blood would not boil inside your body. Of course, once your heart stops pumping, that is a different story.
But on the bright side, you would get a killer tan.
It wouldn’t be pretty and you would definitely have a lot of damage to your body, but it is actually possible for the human body to survive space for a short period of time. Probably double that time if you are a Skywalker…