Astronomical Magic

If you look up at night in Bangkok, you see only a dull, greyish sky. But at my parents' home in the Australian countryside, kilometres away from any unnatural light, the night sky is clear, black and richly dotted with stars that always look the same against the waxing and waning moon. It's easy to understand why our remote ancestors found the night sky a source of wonder, and told tales to explain it.

How a gravitational lens works.

In "Dazzling supernova mystery solved," James Morgan (2014) writes that astronomers now hope to measure more accurately how quickly our universe is expanding. This results from confirming the theory that gravitational lensing by a massive galaxy between it and us explains the previously mysterious exceptional brightness of a supernova, although because the original supernova has now faded, scientists must wait for a similar cosmic event to be discovered.

Articles such as this one, which talk of billions of years and billions of light years, amaze me. They remind me how far we have surpassed our ancestors in understanding the world around us, and how much more there is that we still do not understand. And just our ancestors, brilliant people like Aristotle, got almost everything completely wrong, I also wonder just how much of our best scientific understanding will also later turn out to be false. But we are certainly making impressive progress. We not only know today that the Earth circles the sun, not the other way around as Aristotle and everyone else thought for about 2,000 years, but we have accurate knowledge about the age of our tiny planet and of the entire universe. And almost all of this has come about in the last few hundred years of our species's short existence on this planet.

Back on Earth, our knowledge of life has also been revolutionized since 1859 when Darwin proposed his theory of evolution. We now know, something unimaginable to our ancestors of centuries and millennia ago, that every living thing on this planet is related to every other living thing because life only arose once. Actually, when I think about it, this was not unimaginable to all of our ancestors: the first century BC Roman philosopher Lucretius had a very similar idea to evolution, which he explained in his poem De Rerum Natura [On the Nature of Things], but this insight of Western philosophy was suppressed by the ignorance that the rise of Christianity forced on Europe and the entire Western world for almost 2,000 years.

Thankfully, we have been recovering from the long ignorance and superstition of Christianity for a few hundred years now, and the our progress has been amazing. What will we know and be able to explain tomorrow?

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Reference

Morgan, J. (2014, April 24). Dazzling supernova mystery solved. BBC News Science and Environment. Retrieved April 28, 2014 from http://www.bbc.com/news/science-environment-27118405