It was a rare stellar crash, researchers find
In 1670, European astronomers were all talking about a hot “new” star near the head of the swan constellation, Cygnus. Later dubbed Nova Vul 1670, the star burned bright for two years and then mysteriously vanished. Modern astronomers have long speculated that their 17th century counterparts had observed a nova — an exploding white dwarf. That would make it the oldest recorded observation of a nova. But Nova Vul 1670 wasn’t actually a nova.
Instead, astronomers probably saw two colliding stars, researchers report online March 23 in Nature. With the help of ground-based telescopes in Chile and elsewhere, a team analyzed the cool cloud of dust and gas that today surrounds the stellar remains and found unexpected chemicals. The cloud matches neither the size nor chemical signature of a nova’s remnants.
The best explanation, the researchers argue, is