Here Be Monsters

1,420,405,751* hertz is a very important frequency.  It’s the frequency that hydrogen radiates at, creating radio waves that can be detected far away.  And astronomers can learn a lot about the history and shape of the universe by observing this “hydrogen line” frequency with radio telescopesExtraterrestrial research astronomers also take a lot of interest in the hydrogen line...and it’s for the same exact reason, though the context is different.  It’s thought that if an alien species is capable of communicating with us, wouldn’t they also have figured out the importance of the hydrogen line?  And is it possible that just maybe, they’d use it (or frequencies near it) to communicate with us?  The theory being that the hydrogen line could be used as a kind of universal hailing channel for intelligent species—a representation of a shared understanding of physics. Talk of the hydrogen line was front and center in 1977, when an American astronomer named Jerry R Ehman found a very stro