A joint team of researchers has solved a 30-year mystery regarding the composition of stars in globular clusters.

The discovery is expected to be a critical finding in terms of theories about how the galaxy was formed.

The teams at Sejong and Yonsei universities examined the chemical makeup of 37 globular clusters in the galaxy, confirming that 19 or 20 of them have highly varied compositions.

Until now, scholars had believed the clusters were formed at a similar time, but the discovery proves that even different stars in the same cluster were formed during different periods.

The finding has added weight to the theory that the galaxy was formed by the consolidation of several galaxies.

The study has been published in the British science magazine Nature.