FAST finds two mysterious hydrogen clouds with no visible stars‎

Astronomers have found two clouds of hydrogen near the Whirlpool galaxy that appear to contain almost no stars. The clouds, discovered with China's FAST radio telescope, each contain roughly 3 million times the mass of the sun in hydrogen but have no detectable optical counterpart. Their properties are outlined in a new paper published in the Astronomy & Astrophysics journal on Aug. 4.