I think it’s unlikely that the radio signal detected from the star HD 164595, just 95 light years distant, is an alien broadcast.
That doesn’t mean I doubt life exists outside the Earth. I think it’s likely it does – maybe in our own solar system, underground on Mars or under the ice crust of Europa or Enceladus – or some other place we haven’t thought about yet. But the chance of an intelligent civilisation of aliens, doing what we’d do ourselves (broadcast stuff) is going to be pretty remote. Especially on our back door step.
We have to remember that aliens are going to be alien. Whereas virtually every concept we’ve had of aliens – and especially popularly – has actually been a reflection of ourselves. I can pretty much guarantee that the aliens won’t be big-eyed, big-headed humanoids who’ve arrived to teach us A Better Way. On the contrary, every single one of those tales is made up by humans. If (when) we find alien life, it’ll be alien. And we’ll know. Or maybe we won’t – I mean, would we even recognise it as such?
That’s the issue. How arrogant of us to suppose that (a) life will automatically lead to intelligence (we typically imagine one intelligent species per planet); (b) that this intelligence will be like us, in the sense of wanting to communicate and explore; and (c) it’ll want to communicate in ways we recognise and expect. All of this also pivots on the supposition of some kind of ‘natural’ progress up a chain of ‘advance’ from bacteria to slime to fish to reptiles to dinosaurs to mammals and (eventually) to humans.
Actually, that’s one of the biggest false premises in our society – a product of the ‘age of reason’ and concepts of ‘progress’ that are increasingly being shown to be wrong not just philosophically, but empirically. We now know, biologically, that life doesn’t ‘progress’ to an ‘advanced’ end point. Life just is. It adapts to environments. And it changes for unexpected reasons. If a meteor hadn’t bashed into the Earth 65 million years ago, we’d still very likely be a world of dinosaurs. In some ways we are, of course, because that’s what birds are – something we missed until recently, amidst our conceit of ‘progress’.
That human-centric arrogance when confronted by aliens was the theme of my novella ‘Missionary‘, published last year in the first Endless Worlds compilation. Check it out! Go on, you know you want to.
If (when) we find alien life, I suspect it’ll be bacteria. Or maybe slime. That’s what life on Earth was for much of its history. More complex organisms only appeared late in the piece, after a ‘Snowball Earth’ episode. That happened just 600 million years ago. Earth has been around for 4.5 billion. And for the majority of that time, it seems, we had nothing more complex than single-celled life.
Exactly why and how that exploded into the vast diversity found in the pre-Cambrian oceans is still debated. The ‘snowball Earth’ episode that led to the pre-Cambrian has been a suspect. And what did emerge was alien to us, too. Fossils from that period are so rare and incomplete that we couldn’t decide which way up one creature was meant to be. It was only after a ‘great death’ and the onset of the next geological age – the Cambrian – that anything approaching the body plan we know emerged – the one with a head and face at one end, tail at the other, and four limbs between. It appears to have been purely a chance development – and had things been different, life here could have had other forms again – but apparently the ‘aliens’ we keep half-seeing on deserted roads are meant to have it too. Really?
There’s also the issue of scale. Yes, there are a 300 billion stars in our galaxy alone, exponentially more in the visible universe. The total number of stars has been estimated at 7 x 10 <exp>22. Surely, you’d think, there must be intelligent, civilised life around more stars than just the Sun? I agree. It’s very likely. The problem is finding them. Setting aside the insane distances between galaxies, the distances between stars even within the same galaxy are huge – I posted earlier this week about the ridiculous distance, in everyday human terms, of the nearest star, Proxima Centauri. And who says that an alien civilisation is going to be anywhere near our part of our own galaxy? We’ve seen absolutely no sign in the time we’ve been looking.
Add to that the other factor: time. Our solar system has been around about 4,300,000,000 years, but we’ve had radio-using civilisation for less than 150. The universe is 13.6 billion years old. Who says the ‘other’ civilisation(s) will be here now? Maybe they’ve come and gone. Maybe their time is yet to come. Possibly all of the above is true – we don’t know. But when we start looking at the huge numbers involved, it gets increasingly clear that they’re unlikely to be on our back doorstep, right now. And for all the colossal distance that 95 light years implies, that’s still back doorstep stuff against the scale of the universe.
So what’s my take on the radio signals? Given the background – a weak and wide-band signal picked up by the RATAN-600 telescope last year, but only just announced, I figure it’s likely natural. And that’s not surprising. Radio signals are produced naturally, just as light, X-rays, ultraviolet and so forth are. They’re all part of the one spectrum, electromagnetism. Radio astronomy has been part of wider astronomy for decades. It works exactly as visible-light astronomy, only the wavelength’s longer, and we’ve learned a lot about the universe from it.
I suspect that the signals from HD 164595 are almost certainly natural – but if we study them, we’ll probably learn stuff. And that’s cool. Science is all about discovery.
Eventually, I’m sure, we’ll discover aliens. And it would be very cool if HD 164595 happened to house any. But I’m sceptical.
Copyright © Matthew Wright 2016