I was drawn to the night sky already as a child. As far back as my memory goes, I have always looked at it with a fascination. This feeling has not vanished with time.

People perceive the sight of stars in different ways: some feel mystery; some feel sanctity; some feel boredom. In me, the view of the splendor of the night sky evokes an intrinsic delight and makes me contemplate the infinite reaches of the universe.

Astronomy has therefore become my lifelong hobby. I started attending courses at the Brno Observatory, got a license to operate a large telescope, drew and redrew star charts, did a bit of coding of self-made astronomy software in the 1980s; and began studying physics.

To this day, the night sky continues to fascinate me. To me, it offers more than occasional stargazing and, more recently, astronomy photography. Learning about particle physics and cosmology opens a profound way to a better understanding of our world.

In these fields, science has advanced fundamentally since my student days. For example, we now know that the expansion of the visible part of our universe is not slowing down, but rather accelerating (the cause of it being “dark energy” – a phenomenon not known when my university textbooks were written). We measure gravitational waves and detect collisions of distant black holes; we have confirmed the existence of the Higgs boson particle; and we have mapped the structure of the cosmic microwave background radiation, which helps us better understand the origins of our universe. The search for a “theory of everything”, one that would unify our knowledge of the micro- and macro- worlds and how the four known fundamental interactions (gravitational, electromagnetic, strong and weak nuclear forces) are linked, has also greatly progressed.

And while my professional life took a different course, my amateur interest in these fields also helps me to maintain my mental health and compensate for the rather dismal efforts to save our planet and our civilization. For here, too, things have shifted in the last fifty years: but unfortunately for the worse. Just consider the accelerating rate of climate change and our inability to stop the growth, let alone to rapidly reduce the amount of greenhouse gasses that humanity emits; or the increasing loss of biodiversity and destruction of the last remaining areas of pristine wilderness.

For me, the starry sky is not just an opportunity to take a break and switch my thoughts to something entirely different. Importantly, it also gives me a very different perspective and distance from the plight of humanity.

How We Stopped Being The Center Of The World

Over the centuries, scientific exploration of our universe has mercilessly demolished our naïve and self-centered notions that we, the people (and the gods that care for us), matter most and are at the core of everything.

The idea that our Earth is not the very center around which everything revolves, only began to take hold in the 16th century when a Polish renaissance polymath Nicolaus Copernicus postulated the principle that the Earth occupies no prominent place in the universe. However, as the Italian philosopher and mathematician Giordano Bruno learnt first-hand, it took a long time for the Catholic Church in particular to accept this.

For the next three centuries, the central point of the universe was attributed to our Sun. This illusion persisted even after the discovery that the Milky Way, whose arms we see with our eyes as lighter bands among the stars on the dark sky, is actually a huge starry island – a Galaxy of which we are a part. The idea that we are at the center of this Galaxy, which alone represents the whole universe, lasted until the First World War.

Only after WWI came further revolutionary discoveries that finally disproved these assumptions about our exceptionalism. First, an American astronomer Harlow Shapley showed in 1918 that our place in the Galaxy is not very special and that our Sun – which is only one of the hundreds of billions of stars that make it up – is located insignificantly, quite far from its center.

Next came an American astronomer Edwin Hubble, who used his systematic observations from then world’s largest telescope at the Mount Wilson Observatory in California, to announce in 1924 that the great nebula in the constellation Andromeda was in fact a similar but separate galaxy, located entirely outside our Milky Way. He estimated its distance to be 700,000 light years. Today, thanks to more precise measurements, we know it is about four times further away, but at that time, it was still a staggering distance since the presumed size of the Universe – identical to our Galaxy – was much smaller.

Hubble’s calculation used a revolutionary method of determining cosmic distances that had been invented not long before, by a Harvard astronomer Henrietta Leavitt. It is worth noting that women were not allowed to operate telescopes at that time, but talented female scientists were hired as assistants to senior researchers. In this role, they often performed the tedious work of “live computers”, manually processing observational data. This practice lasted until the 1960s, before the advent of more powerful electronic computers. A story of a group of women who manually calculated spaceflight trajectories and were behind the successful flight of the first American astronaut, John Glenn, is nicely told in the movie Hidden Figures.

In fact, women scientists were instrumental in a number of discoveries that were often attributed to their male superiors. The methodology that Edwin Hubble used was discovered by Henrietta Leavitt. She noticed that certain types of variable stars show a strong correlation between their brightness and the period of its changes, and this turned into an ingenious yardstick for cosmic distances. Her groundbreaking work was published by Edward Pickering, then director of the Harvard Observatory, under his own name. To his credit, however, he mentioned that the paper was in fact written by Miss Leavitt.

Are We Alone In The Universe?

It is less than a century since we learned that our Galaxy is not alone in the universe. That it is neither the largest, nor at the imaginary center of our universe, might have already been suspected, but only subsequent observations and discoveries proved it.

Thanks to images from the Hubble Space Telescope, we now know that there are hundreds of billions of other galaxies in our universe. They form huge clusters and breathtaking cosmic structures stretching as far as we can see.

And let’s face it: our Galaxy’s position in them couldn’t be more random. This means that, whether the world came into being by a random fluctuation or by deliberate creation, our Earth – and presumably ourselves, too – have no special place in it. While I like the notion that the universe created us as a means to observe and understand itself, we should not take it seriously and build upon it some esoteric interpretation of our role in the world.

Our universe obviously has properties that allow for emergence of complex systems, including intelligent life. That, in itself, is not at all a given quality. We can list a number of physical constants whose deviation from their current values by just a few percent would make it impossible for stars to form, or for more atoms to bind into molecules. Without both, life would not have a chance to emerge.

But even that shouldn’t make us feel somehow chosen. There are quite possibly many other universes that are completely cold, dark or without any complex structures. Complex life forms probably arose in ours by a sheer chance, simply because that is where it was possible – and, logically, that is why we observe this (and not a different) universe now.

And if intelligent life originated on one planet, there is no reason to suppose that it will not also appear, sooner or later, somewhere else. There are tens of sextillions of stars in our universe – that’s a twenty-two-digit number! To give you an idea of how big this figure is, imagine that for every little grain of sand we can find on Earth, there are ten thousand stars in the cosmos.

Even taking into account that not every star is of the type of our sun, and not every star has rocky planets with liquid water on them and a large moon to stabilize their rotation, it still seems quite likely that there are more places where complex, thinking, and self-conscious beings will develop at some point.

But given the immense space and time distances, it is probably impossible for them to know about us and each other. This is nicely captured in a cartoon joke that I recently saw on social media:

  • Oracle, are we alone in the universe?
  • Yes.
  • So there’s no other life out there?
  • There is…. They are alone, too.

The Night Sky Under A Threat

These are some of the things that go on in my mind when I’m out at night, stargazing and photographing the stars. It really makes you see the world with more humility.

So, what to take away from the non-exceptional, and probably random, nature of our existence? For some it may cause existential distress, for others the need to believe in something bigger than ourselves, in others it could lead to a cynicism that in such a case, nothing really matters.

I feel differently. Being aware of the amazing coincidence that we are here at all – and with us, many other fascinating life forms – means a strong sense of responsibility. Responsibility to care for this world, not to destroy it and ourselves with it. And the need to find ways to live peacefully a good life.

Still, magical nights under the starry sky cannot be an escape from such responsibility and from the problems to be solved on Earth. This is reminded to me not only by the horrible light pollution we created around cities, but also by the rapidly growing number of satellites. A big worry to me and my fellow astronomers recently is the expansion of the Starlinks network: while their density on the sky already is a problem, Elon Musk plans to launch tens of thousands more.

Without any regulation, and for commercial gain, they now criss-cross the skies over every place on Earth. They disrupt the dark skies and our efforts to capture, with astronomical instruments, the light traveling to us from distant space for millions and billions of years. I have experienced firsthand over the recent couple of months that it has become virtually impossible to take a picture of a space object without multiple lines drawn by the passing satellites.

So, like with our efforts to prevent catastrophic climate change or species extinction, things are not looking very good for the night sky either.

But that is no reason to resign. Instead, a new motivation to get back to work for a better world with humility, hope, and determination!