The globular cluster ESO 280-SC06 is one of the faintest in the Milky Way. Scientists used a spectrograph on the Magellan telescopes in Chile and found that tidal forces caused it to lose between 95 and 98 percent of its mass.
Globular cluster ESO 280-SC06
Scientists working with the Magellan telescopes at the Las Campanas Observatory in Chile used a spectrograph installed on these astronomical instruments to study the globular cluster ESO 280-SC06. The results are published on the arXiv preprint server.
Globular clusters are large structures that are very noticeable even on a galactic scale. They can contain hundreds of thousands or even more than a million stars within a volume of up to 300 light years. Studying them helps us understand the global evolution of our entire galaxy.
However, ESO 280-SC06 is one of the least bright globular clusters in the Milky Way. It is located 67,000 light years from Earth and shows signs of destruction by the tidal forces of our galaxy. Its mass is estimated at 12,500.
Loss of mass
Researchers have focused on studying the red giants that make up ESO 280-SC06. These stars are in the final stages of their existence. They have high luminosity, and their chemical composition can be easily determined using a spectrograph.
The main characteristic here is metallicity, i.e., the content of elements heavier than helium in the star’s composition. It is an indicator of how early this star was born in the Universe. In a new study, scientists calculated how many stars in ESO 280-SC06 belong to the first generation born in the Universe and how many belong to the second.
Astronomers expected the latter to account for about 40%, but it turned out to be 80%. In addition, researchers found other signs of mass loss. They calculated that it originally amounted to 250-500 thousand solar masses.
Thus, during its lifetime, ESO 280-SC06 has lost at least 95-98% of its mass. Moreover, the cluster lost its first-generation stars first. The reason for this was the same tidal forces.
According to phys.org
