by Pippa Goldschmidt
Last Sunday night, Marek Kukula (public astronomer at Royal Observatory Greenwich) gave a talk on astronomy and culture, and showed side by side two diagrams of solar systems. One was a picture of the Copernican model – the first one (at least since the Ancient Greeks) to assert that the Earth was not the centre of our known Universe. The second, a recent diagram of a star and its orbiting planets, looked very similar and is just one example of the huge numbers of planets recently discovered orbiting other stars in the past few years. We don’t yet know if any of these support life.
But the important thing is that this shows the Copernican revolution is ongoing. It didn’t stop after the Copernican model was published in the sixteenth century, or when Galileo’s observations of Jupiter’s moons provided observational evidence that not everything in the sky orbited around the Earth, or the Sun. It didn’t stop when the Sun was shown to be just one of a hundred billion stars in the Milky Way, or when astronomers in the 1920s discovered that the cloudy ‘nebulae’ were in fact other galaxies very similar to the Milky Way.
Not only is the Universe populated with galaxies of stars, these galaxies also consist of dark matter, and in fact there is far more dark matter than the ordinary stuff which makes up stars and humans. And now there is dark energy, required to explain the apparent speeding up of the expansion of the Universe.
With each new discovery, our importance in the grand scheme of things seems to get relegated further and further down the pecking order. We’re nowhere near the centre of the Universe any more, we’re just visible fluff that floats on the surface of a vast dark sea.
But it may or may not be a coincidence that the Universe is difficult, but not impossible for us to understand. We’re inconsequential matter but we seem to be capable of deriving equations which symbolise our understanding of how the whole thing works. Perhaps we’re moving away from the physical towards the metaphorical centre.