Science fiction is a genre committed to the concept of “run before you can walk.” Long before anyone knew whether heavier-than-air flight was possible, writers were imagining travel to other planets. By the time interplanetary space probes were a reality in the 1960s, the storytellers had long since moved on to thinking interstellar.
Today, two or three generations of happy nerds have grown up in a world saturated with science fiction TV shows and movies featuring the word “star” in their titles. When we hear astronomers discuss the detection of possible Earthlike planets around other suns, then, it’s only natural that we want to go there and take a look. We’ve been conditioned to imagine that it’s possible.
In truth, it’s not–at least, not yet. But there may be a way to cheat a little, to get the benefits of interstellar travel without going the full distance. To find out how that might work, I called up Slava Turyshev, a research scientist at NASA’s Jet Propulsion Laboratory who has spent many years thinking about how to bend the rules of space exploration by exploiting the rules of bent light.
Turyshev is one of the world’s leading champions of a mission to a point called the Solar Gravity Lens. He’s also one of the very few champions of this exotic c0ncept, but the more I spoke with him the more excited I became. The idea here is to use the gravitational pull of the Sun as an enormous magnifying glass. Following the rules of Einstein’s general theory of relativity, the Sun warps space around it. A beam of light passing close to the Sun is bent inward a tiny bit as a result, just as would happen if it passed through a lens.