Here’s something that doesn’t happen every millennium: Roughly 35 million years ago, a stray meteorite dropped out of the sky over Virginia and left an impact that helped shape one of the continent’s most distinctive coastlines. This scene of cataclysmic violence now lies beneath the calm waters of Chesapeake Bay. The occurrence of this prehistoric event only recently came to light, and the consequences of that impact will stretch far past our lifetimes. As Diane Casto Tennant makes clear in her new book, it wasn’t the last interesting thing to happen in these parts.