Sure, Star Wars' fully operational Death Star I displayed some mighty superior firepower, but astrophysicist Ethan Siegel has pointed out other serious design flaws in the Empire's ultimate destructive force. That most impressive giant green laser used to obliterate Princess Leia's home planet, Alderaan, would also have tossed out enough heat to turn the Death Star into a sticky, melted mess and generated a recoil to jar the fillings out of every stormtrooper's clenched jaw.
According to Siegel's nerdy science blog, Starts With a Bang!, a more efficient system of planetary extinction would be to wield 1.24 trillion tons of antimatter. Yes, that would do the dastardly deed quite nicely! Here's his full explanation of the diabolical demolition:
It isn't unreasonable that an advanced technological civilization — one that's mastered hyperdrive and faster-than-light travel — could harness, say, the energy from an uninhabited star and use it to produce neutral antimatter. The way we do it on Earth in particle accelerators is relatively simple: we collide protons with other protons at high energies, producing three protons and one antiproton as a result. That antiproton could then be merged with a positron to produce neutral antihydrogen. You might wish for rocky, crystalline structures based on elements like silicon or carbon, but under the right conditions, hydrogen can produce a crystal-like structure.
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 (where a Pascal is a N/m^2), at pressures of tens of Gigapascals (or 10^10 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, hydrogen would actually become an electrical conductor, and is thought to be responsible for the intense magnetic field of Jupiter. 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 an (Earth-like) planet like Alderaan, is a little over a trillion tonnes of metallic antihydrogen, and to transport it down to the planet's surface. Once it hits the planet's surface, it should have no trouble clearing a path down near the core, where the densities are highest.
Got all that? So next time a peaceful planet with no weapons lines up in your cruel crosshairs, go straight for the antimatter attack. You'll thank us later.