Welcome back to the Codex Futurius project, this blog’s never-ending quest to explore the ineffable scientific ideas raised by science fiction. In an earlier entry in the Codex, Jill Tarter of SETI talked about whether we and intelligent-alien species X would recognize each other’s transmissions as such. Now Kevin Grazier–JPL physicist, Hollywood sci-fi adviser, and official friend of Science Not Fiction–looks at the next big question: how we could communicate with any aliens we encounter.
My heroes are in a first-contact situation, meeting an alien face-to-face for the first time. How could my heroes and the alien learn to communicate with each other?
Both knowingly and unwittingly, humans have been broadcasting their presence to the Universe since the 1920s—when coherent transmissions in the radio portion of the electromagnetic spectrum became widespread. Our radio and television broadcasts do not stop at the edge of Earth’s atmosphere; rather they propagate into space at the speed of light. While these signals attenuate with distance, they are detectable nevertheless: NASA still regularly communicates with the twin Voyager spacecraft despite the fact that they are over 100 times further from the Sun than Earth and that each of which transmit data to Earth with less power than a common household light bulb. This means that an alien civilization as far away as 58 light-years could potentially be trying to make sense of “Lucy, you’ve got some ‘splainin’ to do!” (There are 105 G-type stars—ones like our own lovable Sol—within this I Love Lucy-sphere.)