Cosmic antimatter hints at origins of huge bubbles in our galaxy’s center

The Fermi bubbles may have started life as jets of high-energy charged particles

An illustration of the Milky Way with two bubbles shown in blue and purple coming from the center of the galaxy.

Two enormous bubbles of gas (blue and purple in this illustration) extend from the center of the Milky Way. Scientists think they’ve seen positrons, the antimatter counterparts to electrons, that came from the event that may have blown these Fermi bubbles many millennia ago.

NASA Goddard Space Flight Center