TITLE:
How Cloud-9 Observations Could Be Consistent with the Cold Hydogen Dark Matter (CHDM) Theory (a Brief Note)
AUTHORS:
Eugene Terry Tatum
KEYWORDS:
Cloud-9, Dark Matter, Cold Hydrogen Dark Matter, CHDM, Cosmic Dawn, Circumgalactic Medium, RELHIC, Wouthuysen-Field Effect
JOURNAL NAME:
Journal of Modern Physics,
Vol.17 No.2,
February
14,
2026
ABSTRACT: It is suggested that the CHDM theory can be seamlessly integrated into the ΛCDM model and cosmological timeline, including a likely explanation of Cosmic Dawn and “Cloud-9” observations. Confirmatory evidence necessary for acceptance of the CHDM theory may lie in further study of the Cloud-9 dark matter halo or the halo of another RELHIC gas cloud, as described herein. For example, the discovery of an unusually strong 21-cm absorption line within a quasar spectrum in the background of a RELHIC would provide strong evidentiary support for CHDM. Counterarguments to the CHDM theory which focus on “missing” hydrogen baryonic matter appear to be refuted by comparing the Posti & Helmi 20 kpc radius Milky Way halo dark matter mass (635 billion solar masses) to a high-end estimate of the deep space cold neutral hydrogen mass (827 billion solar masses) within the same halo.