M31 in 60 Seconds
Narrator (Megan Watzke, CXC): This image of M31 represents a study of six elliptical galaxies that Chandra made to determine what causes an important type of supernova. At the heart of M31, also known as the Andromeda Galaxy, Chandra detects X-rays. The X-ray glow is partially caused by the aftermath of exploded stars known as supernovas. By examining the properties of the X-rays, scientists have figured out that one class of supernovas in these galaxies, known as Type Ia, are caused when two white dwarf stars merge. Understanding how Type Ia supernovas are triggered is important, since these objects are used to measure vast distances across the cosmos.