Chinese scientists’ new map of the Milky Way turns the tables on cosmic radiation theories

Scientists in China have revealed a new map of the Milky Way, painted in gamma glow, which challenges conventional theories about the universe while also adding a piece to the century-old puzzle of the origins of cosmic radiation.

Using data collected by the Large High Altitude Air Shower Observatory (LHAASO) on Haizi Mountain, 4,400m (14,435 feet) above sea level in southwestern China’s Sichuan province, a team led by researchers from the Purple Mountain Observatory in Nanjing found that our galaxy’s disc was shining with gamma rays at ultra-high energies of up to one quadrillion electron volts (PeV).

The radiation is mainly produced by cosmic rays as they zip through space at nearly the speed of light and collide with interstellar gas. But the scientists wrote in the journal Physics Review Letters on October 9 that instead of being cut off beyond certain points as theoretical models have predicted, the radiation spans a continuous energy spectrum.

“The discrepancy means existing models cannot fully account for LHAASO’s observation results and may need major modifications,” the researchers wrote in a Chinese press release.

Ever since cosmic rays were discovered by Austrian physicist Victor Hess in 1912, scientists have built detectors in space and on the ground to hunt for these mysterious, powerful particles from outer space, Kawata wrote in Physics magazine.