When astronomer Bobby Bus discovered an asteroid passing through the inner solar system on March 2, 1981, it was bright enough to record in his telescope’s photos despite being more than 145 million miles away. This week that same body, now bearing the catalog number 3122 and named to honor Florence Nightingale, is cruising by us at a distance of just 4.4 million miles (7 million km). That’s closer than it’s been since 1890 or will be again until at least 2500.