WASHINGTON — NASA's Fermi telescope discovered a vast halo around a neutron star that could explain why there is so much antimatter near Earth.<br /><br />According to NASA, there is higher than expected amount of antimatter near Earth, a phenomenon which scientists have struggled to find an explanation for. <br /><br />NASA published its study in Physical Review D Tuesday last week.<br /><br />According to NASA's news release, when a giant star dies and explodes into a supernova, its remaining core sometimes becomes a neutron star. <br /><br />The neutron star named Geminga is a pulsar, which constantly discharges electrons and their antimatter counterpart known as positrons into space.<br /><br />As charged positrons and electrons collide with photons from starlight, the added energy charge the light into gamma rays.<br /><br />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. <br /><br />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.<br /><br />According to the study's co-author Silvia Manconi at Aachen University, the pulsar contributed about 20 percent of positrons detected near Earth.
