Science (and Swans) in the Stars

A new kind of violent star collision has been identified near the Cygnus constellation.

The  “Cygnus” constellation—whose name is derived from the Latin word for swan, which it resembles—is at the center of a 340-year-old astronomy mystery.

One of the oldest recognized constellations, in 1670 astronomer and engraver Johannes Hevelius recorded a new star just below the bird’s beak, and published the illustration in the journal Philosophical Transaction (which is still around today).

The star was visible to the naked eye for two years, and then mysteriously disappeared—only to fade in and out a few more times before vanishing for good.  In recent decades, it was thought to be a nova—an exploding star. But now astronomers equipped with powerful telescopes have discovered that the mysterious speck wasn’t a star or a nova at all. Rather, it’s the remains of a of violent collision between a pair of stars, the scientists determined after studying the molecular profile left behind.

Hevelius’ observations of stars—and his artful depictions of their place in the sky—was instrumental in advancing science. “At a time when heliocentrism—the knowledge that the earth revolves around the sun, rather than vice-versa as the church claimed—was still a novel and controversial concept, proving that the universe was a dynamic ecosystem of bodies would be a major feat for science,” science journalist Maria Popova wrote at Brainpickings last year.

There are a number of myths about the cosmic swan. One ancient Greek story suggests that it is Zeus, disguised as a swan to seduce a woman named Leda. Successful in wooing her, they became the parents of Helen of Troy. In another version, Zeus seduces swan-cult goddess, Nemesis, who lays an egg containing Helen; then Zeus puts a swan in the sky to celebrate his success.

Even if you can no longer spot the star in question, you can still find the night-sky bird in the Northern hemisphere this summer