IN HIS EPIC, THREE-VOLUME Burnham’s Celestial Handbook, the astronomer Robert Burnham, Jr., proposes the following metric:
Let one astronomical unit (the mean Earth-Sun distance) equal 12 inches. On that same scale, one light-year (63,000 astronomical units) equals one mile; in our model, that puts Alpha Centauri, our closest stellar neighbor, just over four miles away.
See how big space is? But let’s go further.
Fig. 1.
In October 2022, the James Webb Space Telescope peered 13.1 billion light-years into one tiny slice of our all-surrounding nothingness (see Fig. 1). On our scale, that’s 78,067,190,880,000,000,000,000 miles — or roughly the distance from Earth to just beyond the boundary of interstellar space.
And if your mind is still insufficiently blown, think on this: Except for a handful of relatively close six-rayed stars, every smudge of light you see in Fig. 1 is a galaxy.
A GALAXY.
Contemplating such vasty depths may challenge our sanity. But I also think such a meditation is good for the perspective.
Because in all that unending emptiness, there is only one of each of us: unique, ephemeral, irreplaceable. Enjoy yourself if and while you can — and don’t forget to brush your teeth.