The Search For Life, What’s the Point?

Another mission, another brave “search for life”…

Is it me, or does virtually every robotic foray into space have some ET-searching component attached? In the case of Mars exploration, every lander and rover’s prime directive is find life, evidence of past life, potential for life or the building blocks of life. Even the very first man-made artefact to land (crash) on the planet, the 1971 Soviet Mars 2 mission, was designed to find organic compounds and… any sign of life.

On writing an article yesterday (“Wasteful” Sample Storage Box Removed from Mars Science Laboratory), I started to think that we might just be trying a little too hard and spending too much money on this endeavour. Perhaps there’s another way for us to work out if we are, indeed, an interplanetary (possibly intergalactic?) oasis, or a component of a biological cosmic zoo…

Boredom or Borg?

What if mankind spends the majority of science funding on searching for extraterrestrial life (of the flying saucer kind or the amoeba kind ), only to find our worst fears have been confirmed. Everywhere we look, there are sterile planets, comets and asteroids; not a creature, bacteria or any form of intelligence in sight. We are alone, and the Universe doesn’t care (because there’s nothing out there to be concerned for our loneliness). I’m sure we’d be a bit sad about this outcome.

The Martian landscape. Is it really sterile? (NASA)

So, let’s look at the other end of the spectrum. What if this whole panspermia thing is right; our existence is part of a cosmic law of life. Life is as common as the countless planets that orbit the countless stars inside the countless galaxies. Life. Is. Everywhere.

Will this scenario make mankind feel any better? Will it make us feel as if we actually “belong” and that we’re not actually a stellar mistake? But hold up, what if this means we’re actually a very small cog in a very large engine, what if we are as inconsequential as a colony of busy ants? Even worse, what if we are part of some galactic food chain? Perhaps we’re no longer the purveyor of our assumed infinite potential… we’re actually in the back yard of a billion-year old civilization that doesn’t take too kindly to finding a proto-space faring species (homo-sapiens) living on a small blue dot near an unassuming star called Sol.

The first scenario might seem a little depressing, but it’s a damn sight more appealing than the second outcome. I’d much rather be “bored” pottering around space, safe in the knowledge a Borg-like race isn’t about to squash me.

Looking Under Rocks

Mars rover Spirit cleans a rock ready for analysis (NASA)

In all honesty though, if I had to put money on it, I’d say that we are in a galaxy where life is rare, but not impossible (a scenario that falls between the two above). Life may be the chaotic consequence of the right mix of ingredients that only occurs on a small fraction of planets, or it may take the form of something we don’t fully comprehend.

And so, man builds robots that hunt for life. But why?

Is it out of academic curiosity?
A way for us to understand where we “fit in”?
Help us work out what sparked our existence in the first place?
Just “because”?
All of the above?

What ever the reason, it is a strong natural urge for mankind to seek out our past and what spawned life. If I was a religious guy (which I’m not, but I’ll save that for another day), I’d say that the discovery of the initial conditions for life to form is the Holy Grail; there’s nothing that can top the discovery of how life appeared on Earth and how it might appear on other worlds (except for what caused the Big Bang, of course).

But why the rush? And more importantly, why Mars? Surely the Red Planet has shown itself to be a lifeless dust-bowl by now?

Actually, there are some very good scientific reasons why Mars is believed to harbour signs of life, but so far the armada of life-seeking missions have turned up very little evidence to prove that Mars ever sustained life. With Phoenix’s discovery of the highly toxic (to life as we know it) chemical perchlorate, many believe life cannot be sustained on the planet. Having said that, some organisms use perchlorate in terrestrial deserts as a form of energy. So, life has a few tricks up its sleeves yet.

Although the Mars missions to date have turned up some interesting science, the “life debate” will continue. However, probably the most compelling discovery wasn’t from looking under a Martian rock on Mars, it was from looking under a Martian rock here on Earth.

The structures found in meteorite ALH 84001, announced as revealing the possibility of basic life on Mars (NASA)

The discovery of a meteorite called ALH 84001 (named after its location of discovery in Antarctica, Allan Hills) in 1984 was pretty uneventful until analysis in 1996 unveiled the possibility that this meteorite may have some hidden passengers on board. What made this even more interesting was the fact that the mineral composition of the meteorite revealed that it originated from the surface of Mars. Under an electron microscope, scientists saw what appeared to be tiny bacterial fossils (pictured). This initial evidence was so compelling, President Bill Clinton even held a special TV announcement about the event concluding with, “We will continue to listen closely to what it [the meteorite] has to say as we continue the search for answers and for knowledge that is as old as humanity itself but essential to our people’s future.”

Since the 1996 announcement, very little new information has sprung to light. However, many scientists are sceptical about the knee-jerk reaction that this is evidence of Martian life. Although there is evidence to prove ALH 84001 evolved in a wet environment (which correlates nicely with the ongoing discoveries that Mars was once a lot wetter than it is now), this doesn’t necessarily mean the electron microscope has uncovered alien bacteria. Primarily, scientists cite terrestrial contamination or some mineral formation. In short, the jury is out.

Listening for a Pin Drop 100 Light Years Away

Listening in. The radio telescopes of the VLA in New Mexico (VLA)

At the other end of the scale, the Search for Extraterrestrial Intelligence (SETI) certainly is not looking for bacteria. The program is searching for life a billion years further along the highway of evolution. SETI is a collection of methods designed to detect a signal from an intelligent alien species. Mankind has been leaking radio signals into space for over a century, and television broadcasts for 70 years, so perhaps a sufficiently advanced alien race may also be leaking communications into space.

Add this to the growing number of deliberate attempts by scientists (and advertisers) to message ET (see Messaging Extra-Terrestrial Intelegence, or “METI”), the human race is making a lot of noise (certainly in our cosmic neighbourhood–within 100 light years at least; after all, our transmission can only travel at the speed of light, so our sphere of communication is snuffed out at 100 light years distant).

Although a lot of effort is being put into listening out for alien transmissions (whether the transmission be accidental or a deliberate attempt to find a species like us), nothing has been found. And so far, we’ve had no reply to our attempts at contacting them. Even the famous Wow! signal (pictured below) detected by Dr. Jerry Ehman at the Big Ear radio telescope in 1977 could not be replicated and remains the only significant “discovery” from listening out for ET’s transmission.

1977: The data from Big Ear, signifying a coherent pattern expected from an ET signal (Dr. Jerry R. Ehman)

Although our scientific understanding is developing faster than we fully comprehend, there is still no precedent for a model signal from ET. There are many ways at which we can guess how our transmitted signals may be translated by a hypothetical alien species and we are analysing as many signals as possible in the hope one of them looks “unnatural” (i.e. not generated by a star, quasar or hydrogen cloud). We are listening, but we’re not quite sure what we should be listening for. We are transmitting, but we’re not sure what we should be saying. These are the hazards of trying to communicate with a species we have no idea if they are even there.

The Search For Life. A Fools Errand?

Although the search for extraterrestrial life pushes on, one has to wonder: what’s the point?

In fact, this reminds me of a few debates I’ve had in the last few months, namely:

• Gravitational Waves. Predicted by Einstein, but eluded astrophysicists so far. Is the $400 million Laser Interferometer Gravitational-Wave Observatory (LIGO) a huge waste of money?
• The Higgs Boson. Predicted by the Standard Model, but no direct evidence so far. Why build the multi-billion euro Large Hadron Collider (LHC) when there’s not guarantee we’ll find this famous particle? And if we do, what’s the point?

Although I’m still pretty concerned for LIGO (six-years on and no gravitational wave signal. Really?), I see the LHC as a magnificent chance to advance our understanding of the fabric of the Universe. Even if the Higgs field is not found, the LHC will boost our technological ingenuity to the next rung of scientific understanding. As pointed out by Prof. Brian Cox, the science gained from the LHC is “a journey”, the spin-offs from the techniques applied to accelerating particles around the largest accelerator in the world are varied and very important.

So, going back to the hunt for extraterrestrial life, what if aliens are not found? I think we will have developed very powerful methods of looking deep into the cosmos (i.e. SETI radio telescopes); built highly sensitive autonomous instrumentation capable of digging into the “soil” of an alien planet and then carrying out a host of chemistry studies in-situ (such as Phoenix); developed the field of cryptography, language and data processing. Plus, revolutionary systems such as SETI@home (distributed software that uses the power of individual computers to boost the processing power of huge datasets) have appeared benefiting not only the astronomy community, but other disciplines.

And what if alien life is found? Well, let’s just hope they’re friendly.

And For the Record

Personally, although I’m not adverse to the search for ET, I’m also not totally enthused by a lot of the current missions with the priority to find life (aside from the technological spin-offs we may all benefit from). I’m a space colonization advocate first and foremost, with the belief that we should be doing everything in our power to secure the future Mars colonies before pushing deeper into space (even if we might have to hang around in our own Solar System for a while yet).

Why are we so engrossed in finding extraterrestrial life before securing our own footing in the Galaxy? Mankind needs to expand, we need to move from living on a single planet to exploring what else is out there. Why send robots to search for life on other planets when we could be investing heavily in a manned exploration program to do the same job, only 100 times better?

Unfortunately it all comes down to politics and money…