Faster and Faster

Just trying to be helpful

The thing about science and technology isn’t that they change; it’s that they bring change at an accelerating rate. One place the phenomenon is well-illustrated is the field of astronomy.

In Western civilization at least, for about two millennia we were certain that the Earth was the center of the universe, that the sun and planets rotated around us. Sure, there were a few Greek astronomers like Aristarchus of Samos who postulated the sun was at the center of things, but as Christianity came to dominate Western culture, so did the idea that the universe – a very small universe, with the stars in some kind of fixed “outer crystalline sphere” – rotated around us.

It started to change in the 16th Century, when Nicolaus Copernicus proposed a heliocentric model of the solar system. His work was defended, expanded upon, and corrected by Galileo Galilei and Johannes Kepler. Kepler Herschel discovered Uranus, another planet, suggesting we might not be able to see the entire universe. While the theocracies fought it, because it cast doubt on the infallibility of the Bible, suddenly humanity was no longer the center of the universe.

William Herschel in 1785 carefully counted the number of stars in different regions of the visible sky. He produced a diagram of the shape of the Galaxy with the Solar System close to the center. One hundred years after Galileo, Earth had been demoted from the center of creation to the center of the Milky Way.

In 1838, fifty years later, Friedrich Bessel calculated the parallax of 61 Cygni, one of our closer neighboring stars, at a stunning distance of 11.4 lightyears. Suddenly, the universe was millions of times bigger than Herschel had thought. The earth, even the entire solar system, was just a flyspeck in the cosmos.

In 1917, Heber Curtis had observed the nova S Andromedae within the “Great Andromeda Nebula.” He was able to deduce that the “nebulae” were in fact separate galaxies, some as larger or larger than the Milky Way. The Earth was further demoted from the center of the universe to a planet orbiting a minor sun far out in a spiral arm of one of an inconceivably large number of galaxies, all unimaginable distances away.

In 1931, Edwin Hubble established that the universe was expanding, that galaxies were moving away from the Milky Way, and that the further away a galaxy was, the more rapidly it was apparently moving. Far from being a static place, a created place, the Universe was changing in dramatic ways. And, reasoning it backward, Hubble postulated the “Big Bang,” that at a time in the distant past, some 13-15 billion years ago, the Universe had been a single point. Sure enough, as predicted, the “echo” of the Big Bang is still reverberating through the cosmos, audible to anyone with the right tools

In the 1960s, radio astronomy identified mysterious, powerful objects in the sky and called them “quasars,” an acronym for Quasi-Stellar Radio Source. Only very gradually did astronomers figure out that the quasars were entire galaxies, with super-sized black holes at their cores, unimaginably distant in both time and space. Some are as much as 28.5 billion light years away. The universe grew around us by two more orders of magnitude.

The most recent dramatic change is the discovery that the solar system isn’t unique, that many, many stars have orbiting planets. Thousands of planets have been found around thousands of stars; it’s now estimated that 50 percent of all stars in the Milky Way have a planet the size of Earth or larger in a tight orbit. Extrapolation and incorporation of data from other instruments suggest that virtually all sun-like stars host planets.

In less than 400 years, mankind’s view of the universe has moved us from the very center of creation, unique and very special, to less than a flyspeck in a universe whose size is incomprehensible and contains a number of planets beyond counting. Our precious planet orbits a minor star in a remote arm of a galaxy of 200 billion stars, itself among hundreds of billions of galaxies. Oh, and we can only see a fraction of the matter in that universe.

And some folks still cling to the Old Testament being literally true.

We should expect the universe to only get even stranger even more quickly. Faster and faster.

[A hat tip to Bruce Johnson for the correction on the discovery of Uranus.]