Study Utilizes Gaia Satellite Data to Reveal Key Properties of Collinder 74
A team of astronomers from Istanbul University in Turkey has conducted an extensive study of a Galactic open cluster known as Collinder 74 (Coll 74). Open clusters are groups of stars that are loosely gravitationally bound to each other, providing valuable insights into the formation and evolution of galaxies. Located approximately 8,000 light years away from Earth, Coll 74 has remained a subject of uncertainty, prompting researchers to utilize data from the European Space Agency’s Gaia satellite to investigate its properties. The findings, detailed in a paper published on the arXiv pre-print server and accepted for publication in Physics and Astronomy Reports, shed new light on the nature and characteristics of this intriguing cluster.
Exploring the Member Stars of Collinder 74
Astronomers Talar Yontan and Remziye Canbay from Istanbul University began their study by identifying 102 most likely member stars of Coll 74 within the cluster’s limiting radius. These stars served as the basis for obtaining structural and fundamental astrophysical parameters of the cluster. By analyzing the properties of these member stars, the researchers aimed to gain a deeper understanding of Coll 74’s composition and behavior.
Unveiling the Blue Straggler Stars
Among the identified member stars, Yontan and Canbay discovered four blue straggler stars (BSS) within Coll 74. Blue stragglers are stars that appear younger and bluer than their surrounding cluster members, suggesting that they have experienced a rejuvenation process. The researchers found that these BSS exhibited a flat radial distribution, with three of them located at radial distances of 0.42, 0.88, and 0.98 arcminutes, while the remaining one was situated at approximately 6.25 arcminutes.
Key Parameters of Collinder 74
The study revealed several important parameters of Coll 74. The mean proper-motion values of the cluster were calculated to be 0.960 and -1.526 milliarcseconds per year in right ascension and declination, respectively. The distance to Coll 74 was estimated to be around 9,200 light years, while its age was determined to be approximately 1.8 billion years. The cluster was found to have a radius of 26.9 light years, a total mass of 365 solar masses, and a metallicity level of -0.052. The mass function (MF) slope of Coll 74 was estimated to be approximately 1.34, providing insights into the distribution of stellar masses within the cluster.
Orbital Parameters and Galactic Membership
The researchers also investigated the orbital parameters of Coll 74. They discovered that the cluster has a radial velocity of 20.55 km/s, an orbital period of approximately 291 million years, and an orbital eccentricity of around 0.081. Based on these findings, Yontan and Canbay concluded that Coll 74 is a member of the thin-disk component of the Milky Way galaxy.
The comprehensive study of Collinder 74 by astronomers from Istanbul University has shed new light on the properties and nature of this Galactic open cluster. Utilizing data from the Gaia satellite, the researchers identified member stars, uncovered blue straggler stars, and determined key parameters such as distance, age, radius, and mass. These findings contribute to our understanding of the formation and evolution of galaxies, providing valuable insights into the intricate workings of the universe. As astronomers continue to explore the vastness of space, studies like this bring us closer to unraveling the mysteries of the cosmos.