Hubble Confirms 'Cloud‑9' as a Starless Dark‑Matter Halo Near M94

Overview

• Hubble’s Advanced Camera for Surveys resolved the field and found no stars, verifying a truly starless, gas‑rich system.
• Measurements indicate roughly 1 million solar masses of neutral hydrogen bound by about 5 billion solar masses of dark matter.
• The compact, approximately 4,900‑light‑year H I core lies around 14 million light‑years away in the vicinity of the spiral galaxy Messier 94.
• The work, published in The Astrophysical Journal Letters in 2025, builds on initial radio detections by China’s FAST and confirmations from the VLA and Green Bank Telescope.
• Minor distortions in the radio gas may hint at interaction with M94, and researchers caution that finding additional RELHICs will be observationally challenging.