A three-decade search for the remnant of a nova recorded by Korean astronomers almost 600 years ago has finally succeeded in finding the location of the stellar remnant.
Michael Shara, astrophysics coordinator at New York’s American Museum of Natural History, said the hunt for Nova Scorpii AD 1437 took so long because Korean records did not assign numbers or names to nearby stars, resulting in his team inadvertently looking in the wrong location.
Novae are nuclear explosions that occur at the end stages of massive stars’ lives. Unlike the more powerful supernovae, which completely destroy their precursor stars, standard novae leave the remains of their parent stars intact.
Fifteenth-century Korean astronomers recorded what they believed was a new star that appeared on March 11, 1437 near a known star in the tail of the constellation Scorpius. The bright “new” star was visible for two weeks before disappearing.
Based on the Korean astronomers’ description of the phenomenon, scientists today believe the outburst occurred in a binary system that contained a dead, highly dense white dwarf star and a companion.
Over time, white dwarfs funnel material out of their companion stars, eventually causing them to explode.
Known as cataclysmic variables, binary systems composed of a white dwarf and a regular star experience many novae over time and possibly smaller explosions known as dwarf novae.
By analyzing data collected by the South African Large Telescope and Las Campanas Observatory’s Swope and du Pont telescopes, along with reviewing digital images of photographic plates of the sky taken by Harvard University for more than 100 years, the research team located debris from the nova in the constellation Scorpius.
Calculations of neighboring stars’ motions over the last six centuries confirmed a binary system once resided in the location where the nova was originally seen.
Evidence of dwarf novae in this location on photographic plates from the 1930s and 1940s suggests the binary system is producing both classical and dwarf novae.
The researchers, who published their findings in the journal Nature, hope to image the nova to find out what it looks like now as well as locate several additional novae recorded in history to confirm that classical and dwarf novae have common origins.