Congratulations you are here!

I’ve talked about coincidences and the goldilocks zone before. It’s a train of thought that gets deeper the more you think about it. For some it leads to proof of a divine creator. Simpler souls like me come to more mundane conclusions. Next time you take your existence for granted just mull over some of these amazing thoughts.




If there were no moon, if the moon were smaller or if it were further away the Earth’s orbit would wobble around, as Mars does. The seasons would be irregular, weather would be chaotic and life, if it had got started at all, would have evolved very differently. You would not be here.


If the Earth were just 2 or 3 % smaller it’s gravity would be too weak to hold onto all of it’s atmosphere, the lighter gases including Oxygen would drift off into outer space. 2 or 3% larger and poisonous primordial gases like Iodine and Xenon that actually have dispersed into space would still be here in toxic quantities. Either way you would not be here.


If Jupiter were a bit bigger, a bit smaller, or located somewhere else in the solar system you would not be here Without it’s strong gravitational force the solar system would still be full of dangerous asteroids some of which would hit the Earth with regularity that would wipe out life. A bit bigger and Earth would have been drawn out of its comfortable orbit into a place where you would not survive.


If gravity were a tiny bit weaker, mass would not create the pressures in stars needed for them to shine. Our sun would be a big cold ball of gas. Our planet, if it existed, would be a dark frozen frigid place. If gravity were a tiny bit stronger the stars would be drawn together causing cataclysmic collisions. Either way there’s no chance you’d be here.


Omega is a unit of measurement. It expresses the relative density of the universe. It was set at the moment of the big bang. Had it been just one part in a million billion smaller the universe would already have expanded and cooled. It would be too cold for you. One part in a million billion bigger and the big bang would have collapsed in on itself and the universe would not exist. Nor of course would you.


Given that it is so incredibly unlikely that you are here. How come you are? You may believe that God made you, and you may be right. But here is my more mundane idea. Whatever set of permutations exist give rise to what is here. You are only here because the dice fell the way they did. Had they fallen differently another being would have to ponder the same thought. So for me life is a bit like winning the lottery. You only have to ponder why if you win. The good news is you are here. Congratulations you won the most unlikely prize of all – life!

Mars

Mars doesn’t shine as brightly in the brief summer nights as it did earlier in the year. But it’s still the most tangible, almost touchable world out there. No planet except our own has been more studied, more watched, more visited than Mars. And unless you are very young or very optimistic it is the only planet out there that in our lifetimes we may see visited by our species. We know an extraordinary amount, but there remain great mysteries. What are the enormous caves recently discovered in the Northern mountains, and what’s in them? Was there life on Mars when it was warmer and wetter? Is there life there still?

Intriguingly in 2004 traces of the gas methane were detected in Mars’ atmosphere. Methane is quite unstable and would naturally break down, meaning if it’s there it must be replenished. But by what? There are a few potential sources, but they don’t fully explain it . There is no volcanism on Mars so geological causes are very unlikely. Meteorites and asteroids can carry methane, but the amounts that could be delivered are tiny in comparison to the amounts found. One explanation is that the methane could have a biological origin. On Earth methane is found deep under the ground a product of the breakdown of plants and animals. We use it and call it natural gas. If Mars had life in the past it is possible that the decayed remains of it lie deep under the Martian surface. It is not inconceivable that they have decomposed in the same way. Of course it would require bacteria or something similar to have caused the decomposition. A beguiling possibility emerged last year when NASA announced that seasonal plumes of methane had been discovered coming from the Northern surface of Mars. The area in fact where the caves are located. Could it be that bacteria survive deep underground in those caves, springing into life during the Martian summer?  Perhaps one day an astronaut will descend into one of those deep caves and find out.

Theia and the Goldilocks Zone

Beyond the Earth and Moon there is a vast and empty space, visited just by a few tiny fragments of asteroids drawn inwards by the sun’s gravity, and occasionally a manmade satellite travelling out on a voyage of exploration. As voids go in space this is nothing extraordinary, the immeasurable entity of space is made up almost entirely of nothing.  But the space between Earth and our neighbouring planet Mars is different. This, at least in our terms, is prime real estate space. The region that starts a little in from the orbit of Earth to just outside the orbit of Mars is our star’s Goldilocks zone. Not too hot and not too cold, in fact just right to support life. In many ways it is a careless waste that this huge expanse has just two planets in it, and one of those, Mars, is on the very margins of habitability. But it might have been different. A leading theory about the early Earth says that 4.5 billion years ago the Earth was a slightly smaller planet than it is now, and orbiting close by was another planet, smaller still, called Theia. The theory says that Theia collided with Earth fragmenting both. When gravity reassembled the wreckage a larger Earth and our moon were formed. Theia was no more. But what if events had unfolded differently? We would live in a slightly smaller Earth, with no moon. But just out there would be another world. Perhaps instead of the Apollo moon landing, Neil Armstrong would have stepped out onto the surface of Theia. Perhaps he may have found he was not alone another world in the Goldilocks zone could have supported life of it’s own too. So perhaps it wouldn’t have been Neil Armstrong. Instead a Theian mission of beings would have landed on the Earth first.