spaceSpace and Physics

Scientists Are Investigating Whether Or Not An Alien Probe Just Passed Us By


Stephen Luntz

Stephen has a science degree with a major in physics, an arts degree with majors in English Literature and History and Philosophy of Science and a Graduate Diploma in Science Communication.

Freelance Writer


An artist's impression of Oumuamua, but for all we can see of it, the rocky ridges of an asteroid may really be the sleek likes of an alien spaceship. ESO/M Kommesser via Wikimedia Commons.

Sometimes in science, you have to chase the longshots and take a chance on something so unlikely it feels silly to invest in it, because the payoff would be so huge if it worked. This is why the Robert C. Byrd Green Bank Telescope will be spending time examining the first known interstellar visitor to the Solar System, just in case it is an alien spacecraft.

Back in late October, the PANSTARRS 1 telescope in Hawaii detected what was initially thought to be a comet, dubbed C/2017 U1. As the orbit was plotted it became clear that it could not have originated within the Solar System, and must instead have formed around another star. Further studies revealed no trace of a cometary coma, making it an asteroid.


Even then many people were reminded of the early stages of the classic novel Rendezvous With Rama. In the book, the speedy object turns out to be an alien spaceship, which the crew of the one suitably positioned human spacecraft gets to explore. We lack the technology for that just yet, but are applying what we have.

Further observations increased the parallels. Oumuamua, as the object is dubbed, is exceptionally elongated – indeed its 10-to-1 ratio of length to width is unprecedented for an asteroid – but would make sense for spacecraft designed to minimize friction with interstellar dust.

Still, the chances of this being an alien creation are, well, astronomical. Harvard's Professor Avi Loeb told IFLScience the orbit showed no signs of manoevering, as a spacecraft might. Nevertheless, just in case the biggest science story of the century is currently passing by, the Breakthrough Listen project has announced 10 hours of valuable time on a large radio telescope will be devoted to searching for signals at frequencies of 1-12 GigaHertz. Observations will start at 3pm ET on December 13 (8pm GMT). Loeb observation that, despite plenty of optical observations, only low-sensitivity measurements have been made with radio telescopes, inspired Breakthrough Listen' efforts.

Oumuamua is traveling so fast it's already twice the Earth-Sun distance away from us, which is making observations using telescopes that operate at visible wavelengths increasingly difficult. However, Andrew Siemion of Berkeley SETI Research Center noted it is still less than 2 percent of the distance to Voyager, and we can detect signals from there very well. So if there are any radio emissions in the right wavelengths, the Byrd telescope should pick them up.


Even in the likely event that no signs of alien activity are found, there is always the chance of some other scientifically valuable result. After all, it's agreed there is something unusual about this object beside its orbit, even if most aren't willing to sign on to theories like Oumuamua being a lump of dark matter. The more frequencies at which we study it, the more likely we are to find answers, such as the possibility the Byrd telescope will detect the presence of ice we have so far missed.

spaceSpace and Physics
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