European astronomers have utilized the powerful Very Large Telescope (VLT) to conduct spectroscopic observations of Trumpler 14, an open cluster within the Carina Nebula. These findings, published on arXiv, contribute valuable insights into the characteristics of young, low-mass stars within this cluster.
Open clusters, comprised of stars originating from the same giant molecular cloud, are loosely bound groups of stars. Over 1,000 such clusters have been identified in the Milky Way, and studying them in detail holds significance for advancing our understanding of galaxy formation and evolution.
Trumpler 14, situated around 9,000 light-years from Earth, is a Galactic open cluster located within the Carina Nebula. It boasts a mass roughly equivalent to 4,300 times that of the Sun, spans six light years in diameter, and is approximately 1 million years old. Consequently, it stands out as one of the most massive, youthful, and compact clusters within the Carina Nebula Complex (CNC).
Led by Dominika Itrich of the European Southern Observatory (ESO), a team of astronomers employed ESO’s VLT to delve into the realm of young, low-mass stars within Trumpler 14. Their observations, conducted in 2016 with the Multi Unit Spectroscopic Explorer (MUSE), a second-generation integral field unit (IFU) instrument on the VLT, focused on 780 stars within the cluster. They gathered spectral and stellar data for 717 of these stars, revealing that 339 belonged to spectral type K, 269 were classified as M-type stars, while the remainder were predominantly late G-type stars.
The study unveiled that roughly half of the stars in their sample possessed masses below 1 solar mass, with the smallest star having a mere 0.17 solar masses. This research is notable for its depth in exploring mass characteristics within the CNC and demonstrates the feasibility of scrutinizing low-mass stars even in distant and massive regions.
By examining the age distribution of stars in Trumpler 14, the astronomers determined that the cluster’s age is approximately 1 million years, consistent with previous findings. Importantly, this estimate remains robust regardless of the choice of evolutionary tracks.
The study’s implications extend to our comprehension of the formation and evolution of low-mass stars within a clustered environment. “Low-mass stars are the most prevalent in the Galaxy, yet simultaneously the most susceptible to environmental conditions,” the researchers explained. This investigation represents a significant step toward enhancing our understanding of the formation and early evolution of these low-mass stars within a massive cluster.