The Necklace nebula is a bipolar, post-common-envelope planetary nebula, the central star of which has been shown to have a dwarf carbon star companion. We aim to understand the origins of the Necklace and its dwarf carbon central star. We study the carbon abundance of the nebula through far-ultraviolet spectroscopy obtained with the Hubble Space Telescope. Furthermore, through simultaneous modelling of multi-band light and velocity curves, we attempt to constrain the parameters of the central star system. Puzzlingly, we find that the region of the inner nebula observed with the Hubble Space
Nuclear star clusters are dense and compact stellar systems, with sizes of a few parsecs, found at the centers of many galaxies. Their formation is thought to be closely connected to the assembly history of their host galaxies, and astronomers think that these clusters contain important clues about how galaxies formed and evolved over cosmic time. Recent studies suggest that different formation pathways may operate in late- and early-type galaxies, but the dominant mechanisms and their dependence on galaxy morphology remain unclear. While most observational studies have focused on early-type
Sub-Neptunes - planets larger than Earth but smaller than Neptune - are the most common type of planet in our Galaxy, yet they are entirely absent from our own Solar System. This absence makes them a major focus for astronomers seeking to understand planetary formation and evolution. We recently conducted an international study, as part of the THIRSTEE project, to characterize two such planets orbiting very similar small, cool stars known as M dwarfs: TOI-521 and TOI-912 . THIRSTEE is an observational-based program that aims to shed light on the sub-Neptune population by providing an