Let’s face it, we’re not going anywhere, at least not anytime soon. Anyone who grew up on a diet of science fiction—often Star Trek or Star Wars of one generation or another—has at some point felt the longing for actual, real-world interstellar travel. Then come the hard doses of adult reality.
We have no remotely plausible technology that could transport humans to planets around other stars. We don’t even the technology to send a tiny robotic spacecraft to another star system in a timely manner. (People are thinking about it, but even the proof-of-concept experiments have not yet begun; first test flights are probably decades away at minimum.) Hell, with COVID-19 still raging, many of us are barely making it out of our homes right now.
Or maybe we’re just thinking about the problem the wrong way. Richard Linares, the co-director of the Space Systems Lab, has an idea that could make our science-fiction dreams come true a whole lot faster. We can’t travel to the stars, he acknowledges, but the stars are already coming to us; all we have to do is find a way to catch up with them as they pass. And he thinks he has a way to do just that, using a creative kind of hover-and-attack spacecraft that he calls a Dynamic Orbital Slingshot.
It’s a rather far out concept, but NASA sees some promise in it: The agency’s NASA Innovative Advanced Concepts (NIAC) program just gave Linares and his collaborators a “Phase I” grant to explore the feasibility of the slingshot for a real space mission.
None of this would be happening if not for the mysterious, comet-like object known as ‘Oumuamua, which swung past the Sun in the fall of 2017. Its hyperbolic orbital trajectory flagged it as an interstellar object, meaning that it originated from some place far beyond our solar system. Astronomers had long speculated that comets might escape from other planetary systems and pass through our own, but this was the first concrete proof.
What made the discovery of ‘Oumuamua especially exciting is that it was followed very shortly by the sighting of a second interstellar visitor, Comet Borisov, last August. One such object might be a fluke. Spotting two interstellar comets in such rapid succession means that they must be extremely common; apparently we just weren’t able to detect them before.
Now it is clear that interstellar visitors (of the inanimate kind) pass through our solar system all the time, which means that there are lots of potential targets to explore. And soon we’ll be a lot better at finding them. The upcoming Rubin Obseratory, set to begin operations in 2022, will scour the night sky for anything that moves or changes. By some extrapolations, it could easily identify one new Borisov-like object every year.