Mystery solved: are we alone in the universe?

Okay, so here's the story that caught my attention: a renowned Japanese sword smith has forged a katana made enitrely from the iron of a meteorite. It's called the Tentetsutou, meaning Sword of Heavenly Metal.

Pretty badass, right? But you have to wonder why he made it. There's the obvious answer, of course: badassery is its own reward. But consider the following:  

Fact: Japan has been exploring space since 1969.

Fact: Japan stepped up its game in space exploration in 2003, and since then has landed spacecraft on an asteroid and on the moon. 

Fact: "Giant space monster invades Earth" has been a trope in Japanese movies and anime for as long as there has been Japanese space exploration.

Coincidence? You might think so. But when a renowned blacksmith forges the Sword of Heavenly Metal, there is only one reasonable conclusion to draw: there are giant space monsters, they are coming to invade Earth, Japanese astronomers discovered them years ago, and and also discovered their weakness: they can be killed, but only by a blade forged from the cosmically irradiated metal of deep space. 

We can only assume that there's a super secret training facility in some underground bunker deep beneath the streets of Tokyo. In it, hundreds of martial artists are training for the ultimate honor: to be given the Tentetsutou, and then to fight the aliens singlehandedly in a heroic last ditch effort to save humanity.

Obviously. It's the only reasonable conclusion.