Are we Martians?
As we ponder the possibility of whether aliens have laser guns, we may realise that the best bet for evolutionary success is ... the trusty cockroach.
THERE were a couple of developments this week in answering the age old question of: “Are we alone in the universe?” Firstly, Curiosity – the car-sized robotic rover sent to explore Mars back in 2011 by NASA – this week tweeted (!!!) that it found evidence of an ancient lake on the red planet. Incredible!
And when I say incredible, I mean both the possible existence of water on Mars and the fact that Curiosity has its own Twitter account where it actually finds time between analysing soil samples and dating rocks to post selfies.
Next was a report that life from Earth may have been sent via the Chicxulub impact – the asteroid largely blamed for the extinction of the dinosaurs (bad comet, don’t extinct things) – to Mars. Apparently, Chicxulub hit Earth so hard that it sent “debris hurtling into space”. Debris that Earth organisms could have hitched a ride on before eventually smashing into Mars.
Three meters of rock is enough to shield microbes from the sun’s radiation, though I’d imagine travelling encased in rock is the universe’s equivalent of economy class. And I complain about lack of leg room.
But, these examples give hope to those who believe in other life in the universe. The prior existence of water shows that even if a planet does not currently have life, life may have existed there at some point, and the Chicxulub Debris shows how life surmounts the vast reaches of space.
Given these and other examples, it’s fairly logical to conclude that life has existed at some point somewhere in the great vastness of the universe. But “are we alone in the uni- verse?” is a bit of a time sensitive question, isn’t it? While it would be mind-blowing to learn that life existed on Mars in the past, it would be absolutely brain-imploding to have the Curiosity Rover send back a selfie giving the peace sign with an actual alien.
And that’s the thing about the question of whether we are alone: it’s not only the search for life, it’s the search for life in the universe that can impact us now. Because humans are an impatient species.
Watching TV, you’ll see any number of bleary-eyed individuals claiming to have seen, been abducted by, and even dated extraterrestrials. Fairly dubious to say the least, this is where I differ in opinion. There may have been, and may currently be, other life in the universe, but not necessarily other life in the universe that can impact us right now.
The vastness of the universe is immeasurable. Astronomer Pete Edwards says, “there are as many stars in the universe as there are grains of sand on the Earth”; which is to say, there’s a whole lot of stars.
Many of these stars have their own orbiting bodies so all you have to do is multiply the average number of planets per star with the amount of sand on earth and you’ll get the number of planets. Yeah, that’s a number with a whole lot of zeroes on the end. In a universe that big, it is ludicrous to think that life – no matter how obscure, or how lucky the conditions have to be – didn’t or doesn’t exist.
Now the universe has been around for roughly 13.8 billion years, a duration so long that it is largely incomprehensible. Just to throw more incomprehensible numbers at you, humans have been on Earth for about 200,000 years, which is about 0.00014% of the total time that the universe has been around. That is a really small percentage. We are the mayflies of the cosmos.
Now consider that the “other life” most folks picture finding is sentient – that is thinking, emotional, rational – and usually carrying laser weapons, but let’s forget about that last part. Life doesn’t need to be sentient to be successful, look at the trusty cockroach who has been around for 300 million years and has a track record of evolutionary success that humans aren’t even close to matching.
Being sentient means little to the evolutionary success of a species, so how rare is being sentient in lifeforms? Is being able to think and choose and take selfies on Twitter an evolutionary anomaly? If it is, that makes finding sentient life even more difficult.
The question then becomes: what are our chances of finding other sentient life in this great galactic haystack of time that overlaps ours in terms of not just technology but simple existence?
Taking these three factors – vastness of the universe, the expanse of time, rarity of sentient, technologically-proficient life – I believe that we are, for all intents and purposes, alone in the universe.
But, don’t despair. The same research that led to the theory that the Chicxulub impact could have catapulted Earth life to Mars also has a theory that perhaps a much earlier impact could have catapulted life from Mars to seed Earth. In that case, we’re all Martians and we have to go no further than the mirror to meet a true-life alien.
Is this what an alien looks like? no, it’s just a louse...