'50,000 stars alive': Hubble reveals the stunning chaos of Westerlund 1 cluster

Produced by: Manoj Kumar

Galactic Marvel

Westerlund 1, a supermassive open star cluster, has been observed by the Hubble Space Telescope, revealing its intricate structure and stellar behavior in extraordinary detail.

Massive Cluster

Located 13,800 light-years away, Westerlund 1 boasts a mass between 50,000–100,000 solar masses, making it one of the most massive young star clusters in our galaxy.

Credit : ESA

Stellar Youth

At an estimated age of 5–10 million years, Westerlund 1 offers astronomers a rare chance to study a young starburst environment and understand early cluster dynamics.

Hubble Observations

Led by Lingfeng Wei from UCSD, astronomers used Hubble to measure proper motions of over 10,000 stars, creating the most detailed stellar density and spatial reddening maps of the cluster.

Eccentric Structure

The cluster's shape is elongated northeast-southwest, with an eccentricity of 0.71. Researchers suggest this could result from its molecular cloud origin or merging substructures during formation.

Credit : ESA

Subvirial State

Westerlund 1's velocity dispersion of 3.42 km/s indicates a subvirial state, suggesting high star formation efficiency or inefficient gas expulsion during its creation.

Credit : ESA

Mass Segregation

Stars within Westerlund 1 exhibit mass segregation down to 10 solar masses, confirmed by the crossing time of 300,000 years and a relaxation time of 260 million years.

Credit : ESA

Dense Dynamics

The cluster’s alignment with the galactic plane and its unusual kinematic properties make it a vital key to understanding starburst environments and cluster formation theories.

Representative pic

Cosmic Insights

Published on arXiv, this study provides groundbreaking insights into star formation, stellar density, and the life cycles of massive clusters in our galaxy.

Representative pic