URSABLOG: The Multi-Body Problem

A few years ago, at the end of the first lockdown, I went to the Stavros Niarchos Park, the gardens that surround the Cultural Centre in southern Athens, for an evening event where they had placed some astronomical telescopes for anyone who was interested to look at the planets. It was full Moon, or near it, and the detail I saw through the viewfinder was astounding in its clarity and strangeness. What really impressed me however, and left a mark on my mind and memory, was the image of Saturn and its rings.

I still struggle to understand why. I think part of it is that it is such a strange sight, especially when seen with the naked eye through the telescope, an image that was a bit blurry but also instantly recognisable: a planet with these weird rings at an almost jaunty angle around its waist. The other thing – for me at least – is that it is always there, hovering above me, day or night, but it needs the night, and a telescope, to truly appreciate its presence.

The planets, the Solar System, are the ultimate foundations of our lives. Our planet goes around the sun, doing a complete orbit every 365.25 days (approximately) all the time spinning on its axis – a full revolution every day – sometimes with the northern hemisphere tilting toward the sun (our summer) or away from it (our winter). The Moon, beautiful and beguiling – “What is there in thee, Moon! That thou should’st move my heart so potently?” – gradually revealing and then obscuring its never changing face as it slowly orbits our planet once every 28 days or so, to the delight of Instagram users and disciples of the zodiac and horoscopes everywhere. And Mars, or Jupiter, shining brightly in the evening sky. If these patterns started to change – and they haven’t in the whole of human recorded time – then panic would ensue.

But at the beginning of our planetary system’s formation, there was indeed a great deal of panic and chaos around, many million years before our own planet showed any sign of life. My own assumption in the past had been that the planets had just, you know, kind of formed at different distances from the sun as various elements and lumps coalesced together. This assumption turns out to be far from what scientists now know to a time of momentous upheaval. Our Solar System’s birth was far from peaceful.

It is now generally agreed that the Solar System was formed 4.57 billion years ago, but at some point after its creation it went through a period of chaos and creative destruction, or just plain destruction, and it was only after this upheaval that eventually the planets settled down into their current positions and sizes. This period, the “giant planet instability” caused planets to be pulled about by huge gravitational forces as rogue giant planets bounced around, causing Jupiter’s orbit to jump closer to the Sun, and Saturn, Uranus, and Neptune to be flung outwards. The gravity of these rampaging giants scattered Pluto and other icy bodies out to the distant Kuiper belt, settled the asteroid belt into its current location, and sent countless bodies crashing into the inner Solar System.

Once such body was a Mars-sized protoplanet that crashed into Earth, where a big lump flew off, creating the Moon. But the timing of this chaotic  period, at least according to the journal Science, is hotly contested. For many years, researchers believed this occurred 600 million years after the Solar System’s birth, based on the ages of impact craters mapped on the Moon. But – not least as the moon was formed by a protoplanet crashing into ours – evidence began to emerge fairly recently that it occurred much earlier, and now some researchers are homing in on a more precise date, just 60 million years after the Solar System’s formation.

A more precise date for this event taking place is not simply a matter of scholarly bookkeeping, but immensely important to understanding how it happened, indeed as Graham Edwards, a cosmochemist at Dartmouth University, says: “If we can pin down the when, then we can say something about the why.”

So why does this matter, except to a handful of astronomists? Why does it interest me? I think it’s about placing ourselves in our surroundings: locally, regionally, globally, universally. We all need to have a sense of where we come from, and how we find ourselves to be who we are, where we are, at a particular point in time. We need to be comfortable – as I have written fairly recently – about why we are where we are to be able to move on, positively or otherwise, from there.

I have suffered or profited from periods of instability in my own life. Part of my process in coming to terms with such periods of upheaval and trauma has been to find a cause, a pattern, a reason why things started to change, even when I wasn’t aware of the changes taking place at the time, and indeed trying to pinpoint a time – in retrospect at least – when those changes began.

This applies to abrupt career changes, the illness and deaths of those close to us, the catastrophic end of old relationships, the sudden and explosive starts of new ones, or even that gradual process when an existing relationship takes a turn for better or worse, whether through a change in intensity, or simply a fading off into unimportance.

This also applies in the course of negotiations and deals, the sudden appearance of a ship that might be developed for charter or sale, how things develop, or fail to develop – but rarely as expected – and whether the discussions end in success, failure or indifference. The ability to reflect is a unique human talent, but I have to be careful – and I know this from experience – to make sure that reflection does not just become an excuse to wallow in self-pity, or worse perhaps, to blame others for things that are more probably my responsibility. Or not to hold other people fully responsible for their actions and take it all on me.

And in other situations, as we reflect on a situation and simply cannot work out why something happened, we are usually missing an important piece of information, or relying too heavily on a single piece of evidence. All the logical steps are fine, but cannot lead us to a conclusion because we are simply missing some crucial part of the story.

Despite how self-important and self-centred I may be sometimes, it is both sobering and refreshing to realise that my place in the world is the result of a series of events that are almost mind-boggling in their randomness and chance, and completely beyond my control. This is not just to do with what life choices my parents and grandparents made at certain times of their lives, but all the way back to that spark that led to life on earth in the first place, and further back, to the bashing of planets against each other in an insignificant corner of our galaxy 4 billion years ago.

Our very existence – unless you believe in creationist theories – can only be placed in the context of the results of the movements of inanimate objects, and the influence that they exerted on others, and was exerted on them. But when I looked through the telescope at Saturn and felt so very small and insignificant, I did not say “Sod it, anything I do is of so little importance in the great scheme of things, so I may as well not do anything,” however tempting it might be sometimes.

We are humans, and have, I believe, by a lucky gift of evolution been given the power to change things for the better. We have the ability to think through the consequences of our decisions and actions beforehand, however little we choose to use that power. We have the power of human agency to change things – for better, for worse – in all areas of our lives, however small and ineffectual we think we are sometimes. We cannot change the laws of gravity, and neither can we alter their consequences – “This only is denied even to God: The power to make what has been done undone” – but we can decide to do what can be done.

I feel sometimes that there are huge seemingly inanimate objects in my world that cannot be changed by one human’s action – the market, large shipowning and shipbroking companies, educational institutions, prejudice – but at the same time I have also witnessed the trajectory of these can be changed by human action – individually or severally – and by humans I know personally.

The answer to this multi-body problem may be that however small the actor may be, if they are animate, and intelligent, they have the agency and the leverage to change the trajectory of not only their own lives, but life around them. Whether this is for better or worse, for them or for life, is down to the decisions they take. But none of us is so small not to be able to make a difference, whatever the fault in our stars.

Simon Ward