SpaceTime with Stuart Gary Gary - Series 29 Episode 2 In this episode of SpaceTime , we explore the intriguing history of our galaxy and the secrets of Earth's early water retention. Unraveling the Milky Way's Chemical Bimodality A groundbreaking study suggests that the Milky Way's stellar formation and its unique chemical bimodality may stem from intergalactic gas rather than traditional star formation or galactic collisions. Researchers utilized advanced computer simulations to analyze the formation of 30 simulated galaxies, revealing that the Milky Way's distinct groups of stars, defined by their iron and magnesium content, can emerge through various mechanisms. This research not only enhances our understanding of the Milky Way's evolution but also challenges previous assumptions about the role of smaller galaxies in shaping its chemical structure. Earth's Mantle: A Reservoir of Ancient Water New findings indicate that Earth's mantle may have locked away vast amounts of water during the planet's formative magma ocean phase. Researchers discovered that bridgmanite, the most abundant mineral in the mantle, could store significant quantities of water, potentially equating to the volume of all today's oceans. This study reshapes our understanding of how water was retained during Earth's extreme early conditions and its role in the transition to a habitable planet. The implications of this research may provide insights into the geological processes that sustain Earth's dynamic environment. The Astronomy of Standing Stones Reflecting on archaeological astronomy, we revisit a pivotal study that revealed how ancient standing stones in Britain were constructed with astronomical alignments in mind. This research confirms that the earliest stone monuments, including the Great Circles of Scotland, were intentionally oriented to mark the movements of the sun and moon. By examining the patterns of alignment, researchers established a connection between these ancient structures and the cultural significance of celestial events, illustrating the sophisticated understanding early Britons had of their environment and the cosmos. www.spacetimewithstuartgary.com (https://www.spacetimewithstuartgary.com/) ✍️ Episode References Monthly Notices of the Royal Astronomical Society Journal of Science Journal of Archaeological Science Reports Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-your-guide-to-space-astronomy--2458531/support (https://www.spreaker.com/podcast/spacetime-your-guide-to-space-astronomy--2458531/support?utm_source=rss&utm_medium=rss&utm_campaign=rss) . (00:00:00) This is Space Time Series 29, Episode 2 for broadcast on 5 January 2026 (00:00:47) New study on the Milky Way's chemical bimodality (00:12:30) How bridgmanite in Earth's mantle may have stored ancient water (00:20:10) The astronomical significance of ancient standing stones in Britain (00:25:00) Science Robert: Sleep apnea linked to Parkinson's disease and more news in science Episode link: https://play.headliner.app/episode/30970659?utm_source=youtube