These images showing X-ray data from Chandra and radio emission from the Very Large Array contains the first evidence for a rare type of supernova in the Milky Way. By analyzing over 35 days' worth of Chandra observations, researchers found an unusual pattern of elements such as iron and nickel in the stellar debris. The leading explanation is that this supernova remnant, called Sgr A East, was generated by a so-called Type Iax supernova. This is a special class of Type Ia supernova explosions that are used to accurately measure distances across space and study the expansion of the Universe.