Edith Keeler drops a massive hint early in City on the Edge of Forever that she’s going to tur

Edith Keeler drops a massive hint early in City on the Edge of Forever that she’s going to turn out to be important to the future by being able to predict it.

She starts by saying that “soon, man is going to be able to harness incredible energies, maybe even the atom.” This is pretty prescient for 1930, considering the neutron would not be discovered until 1932 and the first nuclear fission reaction (splitting the atom) would not occur until 1934.

The basic theory behind extracting energy from the atom was already in existence, though; it comes from Einstein’s famous equation E = mc², published in 1905, which states that mass and energy are equivalent. The mass, m, in an atom is tiny, but the speed of light, c, is large, so you get a lot of energy from a small amount of mass.

Keeler goes on to say that this nuclear power will one day be used in spaceships. There have indeed been nuclear powered space missions, including Voyager andNew Horizons, which were heading too far from the Sun to get sufficient power from solar panels. And if we’re ever to manage interstellar travel, nuclear fusion is one of the suggestions of how that might be done.

Her further predictions that nuclear power will be used to find ways to feed the hungry and cure diseases have also, alas, not come to pass. 

Incidentally, the world’s first nuclear powered aircraft carrier was launched in 1960, just a few years before this episode was written. It was called the USS Enterprise.