It’s so hard to know which global threat to worry about most these days. Global warming? Weaponized bird flu? WMD? Well, now you can add the Death Star to your list. Viewers of Star Wars will of course recall the planet-sized spaceship that could blow up planets, but they may have dismissed it as entertainment. The fools…
Such an act of destruction would seem impossible to us–it seemed so to many of the movie’s characters until it happened. But perhaps not, say three students at the University of Leicester in England who last year published a study on the subject in their university’s undergraduate physics and astronomy journal.
The study’s authors start off by making some simple assumptions: The planet being fired upon doesn’t have some sort of protection, like a shield generator. And it’s about the size of Earth but solid through and through (Earth isn’t solid, but the planet’s layers would have significantly complicated the math here). They then calculate the planet’s gravitational binding energy, which is the amount of energy required to pull apart an object. Using the mass and radius of the planet, they calculate that destruction of the object would require 2.25 x 1032 joules. (One joule is equal to the amount of energy required to lift an apple one meter. 1032 joules is a lot of apples.)
The energy output of the Death Star isn’t given directly in the movie, but the space station was said to have had a “hypermatter” reactor that had the energy output of several main-sequence stars. For an example of a main-sequence star, the authors look to the Sun, which puts out 3 x 1026 joules per second, and they conclude that the Death Star could “easily afford to output [the energy required for an Earth-like planet’s destruction] due to to its tremendous power source.”
Fantastic. The only good news is that the Death Star probably couldn’t take out Jupiter without self-destructing. Perhaps the need to get to larger planet explains China’s recent burst of enthusiasm for manned space flight?
[H/t: Vanessa Parra.]
