The Milky Way seems to be losing weight! According to the report of the British New Scientist website on the 11th, American scientists measured the fast radio burst (FRB) passing through the Milky Way Galaxy, which showed that compared with the amount of dark matter, the normal matter (baryonic matter) in and around the Milky Way Galaxy was less than people expected, 40% lower than other parts of the universe. Relevant research is published on the website of the pre-printed paper. The Deep Synchronous Optical Array (DSA), located in California, USA, has 110 radio antennas, 63 of which are still in operation, and is specially used to detect FRB and trace its galaxy. In the process of tracing, the detector can also calculate the amount of matter between the galaxy and the detector by measuring how these substances absorb the radiation from the FRB, which is a bit like determining the thickness of the fog through the light emitted by the fog. Vikram Ravi of the California Institute of Technology presented the latest results of one of their measurements at the meeting of the American Astronomical Society held in Seattle on the 9th. He and his colleagues used the light from an explosion called FRB 20220319D to study the matter in the halo of the galaxy. FRB 20220319D originates from a galaxy about 163 million light-years away. The halo of the Milky Way is a roughly spherical cloud composed of stars, gas and dark matter, in which the galactic disk is embedded. Ravi said: "Throughout the universe, the proportion of baryonic matter is 16%, and the rest is dark matter, but the proportion of baryonic matter in the Milky Way Galaxy is much lower. The observation results show that the proportion of baryonic matter in the halo of the Milky Way Galaxy is only 9.6%, 40% less than the whole universe." Ravi explained that the numerical simulation of galaxy formation shows that various feedback mechanisms often eliminate the mass of the Milky Way Galaxy. These mechanisms include strong winds generated by supernovae and massive stars, which blow matter out of the galaxy when they form, and similar effects produced by supermassive black holes in the center of the galaxy. If this measurement result is confirmed by future observations, it may prove that the Milky Way is turbulent in its youth, and matter is thrown into intergalactic space. (Outlook New Era)