Afterglows

Abstract

The Milky Way consists of 100,000 million stars. It appears sedate, placid, unchanging as it curves, a river of stars across the bowl of the night-sky. We know, however, that it is a dynamic structure; it must have had a violent youth in which it was cobbled together from various bits and pieces, from blobs of dark matter, streams of gas, and smaller stellar systems.

When I heard the learn’d astronomer, When the proofs, the figures, were ranged in columns before me… How soon unaccountable I became tired and sick, Till rising and gliding out I wander’d off by myself, In the mystical moist night-air, and from time to time, Look’d up in perfect silence at the stars.

—Walt Whitman, “When I heard the learn’d astronomer”