Djorgovski 2 was captured back in 1978 and since then has puzzled astronomers’ researches.
The globular cluster was recently in the spotlight. A team of researchers performed a series of investigations to find more about the peculiar cosmic feature.
The findings are quite intriguing. It seems that Djorgovski 2 has multiple stellar populations. How is this possible?
Here is what you need to know.
Djorgovski 2: Mystery Solved?
Evan Butler and Andrea Kunder from the Saint Martin’s University in Olympia, Washington, teamed up and made quite the discovery. Their goal was to get more details of the chemical composition of Djorgovski 2’s stars. For the study, the team utilized data from the APOGEE (the Apache Point Observatory) and SDSS (the Sloan Digital Sky Survey).
The team’s work and findings
The researchers isolated seven stars in Djorgovski 2 with strong velocities, elemental abundances, metallicities, and proper motions from ESA’s Gaia satellite. The results show that the globular cluster has a metallicity of around -1.05, a bit higher than the value reported by previous investigations.
Also, an important spread in the abundances of aluminum, carbon, nitrogen, carbon, and sodium was found in those stars. The obtained amounts are indicative of multiple stellar populations.
Furthermore, the researchers discovered that the average silicon to iron abundance ratio reaches a level of approximately 25 dex (typical for in situ bulge clusters).
The research also suggested that some RR Lyrae stars initially believed to be field stars, are part of Djorgovski 2. The length of the cluster was measured to be around 28,134 light. Such a thing is in accordance with previous measurements.
Djorgovski 2 So Far
Djorgovski 2 was discovered in 1978. Scientists determined its nature as a globular cluster situated in a galactic bulge, one of the closest globular clusters to the core of our galaxy.
Djorgovski 2 is also one of the most ancient globular clusters. Such a thing means that it might have seen the whole history of the Milky Way. It could also be essential in advancing the knowledge about our galaxy.