Hubble Discovers Starless Cloud9 Near Messier 94

Astronomers using NASA's Hubble Space Telescope have discovered a starless cloud of gas and dark matter, dubbed Cloud9, located about 14 million light-years from Earth on the outskirts of the spiral galaxy Messier 94. This object, the first confirmed example of a long-theorized cosmic structure known as a Reionization-Limited H I Cloud, or RELHIC, represents a relic from the early universe that failed to form stars, offering new insights into galaxy formation and the invisible substance that dominates cosmic mass.

The discovery, detailed in a study published in The Astrophysical Journal Letters, was first hinted at three years ago during a radio survey conducted by China's Five-hundred-meter Aperture Spherical Telescope, or FAST, in Guizhou province. Follow-up observations with the Green Bank Telescope and the Very Large Array in the United States provided additional confirmation of the cloud's neutral hydrogen content, but it was Hubble's Advanced Camera for Surveys that definitively ruled out the presence of any stars. "Before we used Hubble, you could argue that this is a faint dwarf galaxy that we could not see with ground-based telescopes," said lead author Gagandeep Anand...