Cloud-9 (RELHIC)
Cloud-9 is a REionization-Limited-H i Cloud (RELHIC), and possibly a starless dark matter galaxy.[1] This RELHIC may have a mass 5 billion times that of the Sun and was found in the vicinity of the spiral galaxy M94, in the constellation Canes Venatici.[2]
First identified by the Five-hundred-meter Aperture Spherical Telescope (FAST) in 2023 and confirmed by NASA's Hubble Space Telescope in early 2026, Cloud-9 is the first confirmed example of a failed galaxy of a type predicted by the Lambda CDM cold dark matter cosmological model, having captured hydrogen gas but failed to initiate star formation.[3][4][5][6][7]
References
- ^ Benitez-Llambay, Alejandro; Navarro, Julio F. (September 2023), "Is a Recently Discovered H I Cloud near M94 a Starless Dark Matter Halo?", The Astrophysical Journal, 956 (1): 1, arXiv:2309.03253, Bibcode:2023ApJ...956....1B, doi:10.3847/1538-4357/acf767, ISSN 0004-637X
- ^ "Astronomers may have found a galaxy that's all dark matter, with no stars", Sky at Night, BBC, 2 November 2023, retrieved 2024-01-22
- ^ Anand, Gagandeep S.; Benítez-Llambay, Alejandro; Beaton, Rachael; Fox, Andrew J.; Navarro, Julio F.; D’Onghia, Elena (2025-11-10), "The First RELHIC? Cloud-9 is a Starless Gas Cloud", The Astrophysical Journal Letters, 993 (2): L55, arXiv:2508.20157, Bibcode:2025ApJ...993L..55A, doi:10.3847/2041-8213/ae1584, ISSN 2041-8205
- ^ Cloud-9: a new celestial object found by Hubble, European Space Agency, retrieved 2026-01-09
- ^ NASA's Hubble Examines Cloud-9, First of New Type of Object, NASA, 2026-01-05
- ^ [email protected] (2026-01-07), "Scientists have found a new kind of object in deep space. And it could help solve one of the Universe's biggest mysteries", Sky at Night, BBC
- ^ Ahart, Jenna, "Do All Galaxies Need Stars? Astronomers Discover a New Class of Astronomical Object", Scientific American