China's FAST Telescope Detects Over 156,000 Neutral Hydrogen Sources, Reshaping Early Universe Understanding

China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) has made a significant breakthrough in radio astronomy by detecting 156,411 neutral hydrogen sources across nearly half the sky. These findings, published as a cover story in *Science China Physics, Mechanics & Astronomy*, are expected to advance understanding in galaxy formation and evolution, dark matter distribution, and large-scale cosmic structures. Neutral hydrogen, formed about 13.8 billion years ago, carries crucial information about the universe's transition from darkness to light.