Solving a 400-year-old supernova riddle

From Seattle, at a meeting of the American Astronomical Society

TYPECASTING. X-ray portrait of the remnant of Kepler’s supernova reveals that the stellar explosion was type 1a, meaning it started as a white dwarf. Reynolds, et al., NASA, CXC

In 1604, an assistant to the astronomer Johannes Kepler discovered an object that shone brighter than any star in the heavens.