Scientists identify a thermonuclear supernova as the origin of antimatter in the Milky Way

Antimatter is made up of antiparticles, just as matter is made up of particles. When matter and antimatter react, they annihilate each other in gamma ray energy bursts. The center of the Milky Way galaxy has been a known source of strong gamma rays since the 1970s, indicating the presence of antimatter. However scientists were not aware of any reason as to how the antimatter got there, and it was a cosmic puzzle. Now, a team of researchers from lead by the Australian National University (ANU) have discovered the source of the antimatter. The team first ruled out the supermassive blackhole at the center of the galaxy, and dark matter as the sources of antimatter. Dr Roland Crocker, an ANU researcher said, “Our research provides new insight into a part of the Milky Way where we find some of the oldest stars in our galaxy.” A new paper published in Nature Astronomy shows that a series of weak supernova explosions lead to a collision between two white dwarf stars. The two white dwarf stars formed a binary system, and spiraled closer and closer to each other. The smaller of the two white dwarfs lost its mass to the larger star, and became a helium white dwarf star. The larger of the two in the binary system became a carbon-oxygen white dwarf star. The binary system then started losing energy to gravitational waves, causing the two stars to collide into each other. The carbon-oxygen white dwarf star then ripped apart the helium white-dwarf star, which formed a dense shell covering the larger star. This formation resulted in a thermonuclear supernova in the heart of the galaxy, which is the source of the antimatter, as well as the gamma rays.