Clues from the Cosmic Past: Unraveling the Chemical History of NGC 2298
This study analyzes 13 stars in the globular cluster NGC 2298 using the Gemini South telescope. It identifies two stellar generations with distinct light element patterns and finds notable variations in heavier elements like Sc, Sr, and Eu. These differences suggest complex, uneven early chemical enrichment from supernovae and rare r-process events, highlighting the cluster’s dynamic formation history.
Unraveling the Mystery of the Faintest Galaxies: A Deep Dive into Sagittarius II and Aquarius II
Astronomers used the Gemini/GHOST spectrograph to study Sagittarius II (Sgr2) and Aquarius II (Aqu2), two faint Milky Way satellites. Their analysis suggests Aqu2 is a dark matter-dominated ultra-faint dwarf galaxy, while Sgr2 remains ambiguous, possibly a star cluster. Chemical signatures and star movements were key to these classifications. The study highlights the difficulty in distinguishing faint galaxies from clusters and the need for further observations and simulations.
A Chemical Census of the Milky Way’s Nuclear Star Cluster
The study analyzes the chemical composition of nine stars in the Milky Way’s Nuclear Star Cluster (NSC) using infrared spectroscopy. Most elements match the inner bulge, suggesting a shared history, but sodium levels are unexpectedly high, hinting at a unique enrichment process. This research provides crucial insights into the NSC’s evolution and its connection to the Milky Way’s central regions.
Exploring the Heart of the Galaxy: Chemical Secrets of the Milky Way's Nuclear Star Cluster
The study analyzed the chemical compositions of nine stars in the Milky Way's Nuclear Star Cluster (NSC), focusing on α-elements like magnesium, silicon, and calcium. The results reveal that the NSC shares similar chemical trends with the Galactic bulge and thick disk, indicating a shared evolutionary history characterized by rapid star formation over billions of years. This challenges theories of recent dominant starbursts in the NSC.
Decoding WASP-43b: Exploring Water in a Distant Gas Giant's Atmosphere
Scientists studied the atmosphere of the hot Jupiter WASP-43b using high-resolution spectroscopy, detecting water with a precise abundance measurement. Other molecules like methane and carbon dioxide were not found, and the carbon-to-oxygen ratio was constrained to less than 0.95. The findings align with prior observations from JWST, supporting a clearer day side and cloudy night side. Future telescopes may uncover more details about the planet's atmospheric composition.