Yearning for Extraterrestrials

A short time ago I commented on the search for intelligent extraterrestrials  (see A Cosmic Contemplation). I admit to being sceptical of this endeavour. However, I might be less sceptical if star-gazing scientists were, shall we say, more scientific and not so prone to starry-eyed (forgive the pun) speculation dressed up as science. More grist for their more fantastical posturing came their way recently, courtesy of Russian billionaire Yuri Milner.

Mr Milner is funding a new US$100 million, ten-year, exploration of the outer limits, with the public backing of Stephen Hawking. Reportedly, some of the world’s largest radio telescopes, including the one at Parkes, will be used to scan for distinctive radio signals that could indicate the existence of intelligent life. The project is named ‘Breakthrough Listen’.

Let’s be clear. How Milner spends his money is entirely up to him. Many astronomers and cosmologists will find gainful employment. And, no doubt, valuable and interesting information will be gained from this intense cosmic listening. This listening will reach the star systems nearest to earth and then onto the nearest 100 galaxies; so it is claimed.

Mind you, there is definitely no plan to send signals the other way. Why the heck not, the man or woman in the street might say in their scientific ignorance? They don’t understand. They’re just not smoking the same pipe as are scientists.

Hawking was reported to have said that some form of simple life on other worlds seemed very likely, but that the existence of intelligent life was another matter and humankind needed to think hard about making contact. He was quoted thus: “A civilization reading one of our messages could be billions of years ahead. If so, they will be vastly more powerful and may not see us as any more valuable than we see bacteria.”

Listening to Hawking should be a reminder that scientists, whatever their IQs, often have less common sense than the average Joe Blow. They are susceptible to flights of fancy. Humankind being fried by global warming is an example. Or, alternatively, being zapped in some unimaginable way by aliens, if only they knew we were here.

Be not afraid children. If, in fact, these extraterrestrials are billions of years ahead of us, why in the world would anyone think we will find them before they find us? On reflection, be afraid. Maybe they have already found us and are living secretly among us, disguised as greenies and United Nations’ bureaucrats, intent on our destruction. That would explain a lot.

Let’s dissect Hawking’s wisdom a little further. “Simple life on other worlds seems very likely.” Tosh! As Astronomer Royal Martin Rees (Just Six Numbers) puts it: “We still don’t know how or where life got started. A torpid volcano is now more favoured than Darwin’s ‘warm little pond’.” So, unless the odds of life emerging from inanimate matter, and under what conditions, are known, and they are not, Hawking’s statement is mere speculation. Speculation itself is fine, but it should be clearly labelled as such.

According to Hawking, we need to think hard about making contact with extraterrestrials. A first thing to say is that the nearest star to the earth outside of our solar system is 4.3 light years away, but most are many thousands of light years away. When you get to other galaxies; the nearest is Canis Major Dwarf and that is 25,000 light years’ away.

So, unless any very advanced planetary inhabitants, within this, the nearest of the galaxies to ours, have discovered how to travel faster than light, a message sent today will take at least 50,000 years to be acknowledged. Equally, these advanced extraterrestrial barbarians – out to do us harm – would take at least 50,000 years and counting before they could invade or zap us from distance.

Still, I suppose we have to think of far-flung future generations and the tribulations they would face as a result of being invaded or zapped by aliens, if only we are silly enough to reveal our presence. In fact, I don’t know whether we shouldn’t shut down every sign of advanced civilisation lest they detect us. At once, all of a sudden, Agenda 21 begins to make perfect sense. It is a defensive measure against potential alien onslaughts.

Another problem with project Breakthrough Listen is that it will merely scratch the surface. According to US planetary scientist Dr Sara Seager, one hundred galaxies is about one billionth of the number of galaxies in the universe. All of that putative teeming life within very distant galaxies, including any within the most recently discovered galaxy (with the catchy name of z8_GND_5296) — about 30 billion light-years away as the crow flies — will remain undiscoverable. On the other hand, in a sense, this is promising.

If, after ten years of listening, nothing is heard from the nearest 100 galaxies, the sky is the limit, literally. More billionaires will have scope to employ more astronomers and cosmologists to search the next 100 galaxies, and so on, as telescopes improve; almost into infinity. Moreover, finding life at greater distances from earth will make extraterrestrial invasion less likely; which will be a Godsend.