What if?
On the off chance that BLC-1 turns out to be the real deal, it would raise the question of whether humanity should send a reply — something within our current means. Our message could potentially stimulate a response in less than a decade, starting an interstellar dialogue well within the lifetimes of most people alive today. That’s an incredibly exciting prospect.
But this possibility also raises concerning questions about our conversation partners: Who are they? What are their motives? Do they pose a threat? Technologically advanced beings at Proxima Centauri could reach Earth in a few decades if they can traverse interstellar space at an appreciable fraction of the speed of light. After all, Breakthrough Initiatives is planning just such a venture with its
Starshot project, which plans to use a powerful laser to accelerate about a thousand ultra-lightweight, centimeter-sized craft attached to light sails. Such craft can theoretically attain 15 to 20 percent the speed of light, meaning they could reach the Proxima system in 20 to 30 years.
And what would such a nearby alien civilization know about us?
“I find it difficult to believe that a technological civilization on Proxima Centauri would not know about life on Earth,” says astrobiologist Jacob Haqq-Misra of the Blue Marble Space Institute of Science. “The only way they would not know is if they are almost exactly at our present-day level of technology, so that we are discovering them the same time they are discovering us. This is generally unlikely, because even a thousand-year difference between our two civilizations — a short time in astronomy — would lead to drastic differences in our detection capabilities.”
Next steps
The Breakthrough Listen team is now working on two scientific papers that will report more details on BLC-1. They are also undoubtedly trying to identify all possible sources of terrestrial interference, as well as determine whether the signal repeats by observing again with Parkes and other radio telescopes, or combing through archival data.
At least for now, BLC-1 is the most tantalizing SETI signal since Ohio State University’s Big Ear radio telescope picked up the powerful
“Wow!” signal on August 15, 1977. That 72-second narrowband transmission emanated from the direction of Sagittarius. The signal has never repeated, but it also remains unexplained.
If BLC-1 is simply — as is most likely — human interference, then it's no big deal, perhaps just a bit of an embarrassment to whomever leaked the story to
The Guardian. But if BLC-1 is a bona fide extraterrestrial signal, it could change the course of world history. An alien radio transmitter just 4.25 light-years from Earth would be a game changer. No doubt this is why the discovery team has gone silent and is working hard to get its analysis right.
Even if BLC-1 turns out to be human radio interference, detailed analysis will help SETI researchers refine their search parameters to make later searches more efficient.
“Ultimately, I think we’ll be able to convince ourselves that [BLC-1] is interference. But the end result will certainly be that it will make our experiments more powerful in the future,” Siemion told
National Geographic.