A sad consequence of the Thirty Meter Telescope controversy is that some TMT opponents have taken to belittling the entire field of astronomy, claiming that it has never discovered anything of practical consequence. Of course, most people on Earth — including the TMT protestors — do not think material gain is the end-all-be-all of existence, but that is a different conversation. How has astronomy ever improved our material lives?

In ancient times, astronomy was one of the only sources of regularity in a chaotic world populated by cruel and fickle gods. By looking at the sun and stars, the ancients could determine the time of day and year.

The sun and stars told farmers when to sow and when to reap, and generals when to start or end their campaigns. It allowed the precise long-term planning that great civilizations depend on.

Aside from enabling agriculture and bureaucracy, astronomy also allowed sailors to navigate the seas. Even in the Homeric epics — the earliest literature we have from ancient Greece — Homer explains how sailors use the constellation Ursa Major (the Big Dipper) for navigation. Ursa Major circles the north celestial pole, he explains in not quite those words, and never dips into the waters of Oceanus.

Odysseus keeps it on his left to sail to the east. Celestial navigation allowed the Polynesians to cross the vast Pacific, and allowed distant empires to exchange goods and knowledge. One of these trading empires, the Phoenicians, spread their alphabet so widely that it became the ancestor of almost every alphabet in use today.

In the 16th century, astronomy was the science that started the Scientific Revolution. Copernicus challenged the age-old geocentric model of the universe with a heliocentric model. Precise observations by Brahe enabled Kepler to discover the exact shape of planetary orbits.

This, in turn, enabled Newton to develop his laws of motion, explaining with the same elegant laws both the motion of the planets and of objects on Earth. Newton’s “Principia” marked the birth of modern science. It gave us confidence that mathematics, observations, and reason are enough to understand the natural world — a revelation that forever transformed the world, giving us a quality of life that Newton could not have dreamed of.

Flickr: Mike Durkin

Fast forward to the 19th and 20th centuries, and astronomy continued to make major contributions to mankind. The first hints of quantum mechanics came from observing hydrogen absorption lines in the sun, as atomic hydrogen was difficult to make in the lab. It was anomalous changes in the orbit of Mercury that first indicated something was wrong with Newtonian mechanics — a realization that would lead to the discovery of general relativity.

After Einstein discovered general relativity, it was astronomers who verified it by observing a total solar eclipse in 1919, followed by a binary neutron star system in 1974 and a black hole in 2019. Quantum mechanics and general relativity are the cornerstone achievements of 20th-century physics. Without general relativity, GPS satellites would not be possible; without quantum mechanics, there would be no modern electronics.

As we look towards the future, astronomy tantalizes us with its potential to transform our understanding of the universe and our place in it. TMT will investigate dark matter and dark energy, which together make up 96% of the universe, but which our current models of physics cannot explain.

With any luck, dark matter and dark energy will be to us what the precession of Mercury and the missing lines in the sun’s spectrum were to earlier generations — signposts to fundamentally new physical theories. In addition to fundamental physics, astronomers will also discover countless near-Earth asteroids and distant exoplanets, some of which may harbor observable signs of life — signs that TMT is well suited to pick up.

Stepping Stones

Within this century, near Earth asteroids may provide near-limitless resources for our economy and serve as stepping stones in our expansion across the solar system. In the far future of our species, an exoplanet with life may be an aspirational travel destination, driving humanity onwards to become a star-faring civilization.

Of course, it is impossible to predict exactly what discoveries astronomy will make and what economic benefits they will bring. The Stone Age hunter-gatherer stargazers who noticed regularities in the heavens did not know that their discoveries would one day lay the foundations of civilization.

“The sun and stars told farmers when to sow and when to reap.”

When Brahe meticulously observed the planets by eye, he did not know that his observations would play a critical role in ushering in the Enlightenment. When Angstrom and Huggins observed dark lines in sunlight, they could not have predicted the discovery of quantum mechanics, let alone the invention of semiconductor electronics. Undoubtedly, many of these astronomers’ contemporaries thought they were wasting their time, but every person alive today is in their debt for having done so.

So, what has astronomy ever done for us?

Aside from guiding humanity into civilization by making agriculture and navigation possible; kickstarting the Scientific Revolution that created the modern world; and leading to the discovery of quantum mechanics, without which modern electronics would be impossible, astronomy has given us nothing. Nothing, that is, aside from technological spin-offs like charge-coupled devices; aside from the cosmic perspective eloquently articulated by Carl Sagan’s “Pale Blue Dot,” but remarked upon even 2000 years ago in Cicero’s “Dream of Scipio”; and aside from the inherent value of knowledge — but those go without saying.