On a recent trip to London, my family and I had a chance to visit the Royal Observatory in Greenwich. I’ve always been fascinated by the challenges faced by sea-faring explorers of the 18th century, who needed accurate methods to track a ship’s location on the ocean but hadn’t cracked the problem until John Harrison perfected his marine chronometer in 1759 (which is on display in the observatory). We can draw direct parallels between space-based observatories – seeking answers to the big questions about our place in the Universe – and those intrepid oceanic explorers who set sail with the goal of exploring the unknown reaches of the world. The James Webb Space Telescope, with its huge sun shield deployed like the sail of a cosmic ship, is the latest of our great explorers, orbiting an imaginary point a million miles away as its giant golden mirror array captures light that has been streaming across the Universe for billions of years.
How lucky are we to live in a time when we can work with this ancient light? And
