Monster halo could unravel the Earth's antimatter mystery

  • 4 years ago
WASHINGTON — NASA's Fermi telescope discovered a vast halo around a neutron star that could explain why there is so much antimatter near Earth.

According to NASA, there is higher than expected amount of antimatter near Earth, a phenomenon which scientists have struggled to find an explanation for.

NASA published its study in Physical Review D Tuesday last week.

According to NASA's news release, when a giant star dies and explodes into a supernova, its remaining core sometimes becomes a neutron star.

The neutron star named Geminga is a pulsar, which constantly discharges electrons and their antimatter counterpart known as positrons into space.

As charged positrons and electrons collide with photons from starlight, the added energy charge the light into gamma rays.

Since the path of gamma rays are scrambled by the magnetic fields they encounter, scientists have been unable to trace the positrons back to their origins until now.

Using the Fermi data, a NASA affiliated team removed background gamma radiation from the readings and determined that Geminga is in fact the source of the extra positrons.

According to the study's co-author Silvia Manconi at Aachen University, the pulsar contributed about 20 percent of positrons detected near Earth.