{
  "id": 20184681,
  "title": "Astronomers redefine star cluster in a new study",
  "url": "https://urgent.news/2026/11/15/astronomers-redefine-star-cluster-in-a-new-study",
  "topic": "world",
  "section": "World",
  "published": "2026-11-15T14:17:31.000Z",
  "source": {
    "name": "The Hindu",
    "slug": "the-hindu",
    "url": "https://www.thehindu.com/news/national/karnataka/astronomers-redefine-star-cluster-in-a-new-study/article71705010.ece"
  },
  "original_language": "en",
  "account": "Astronomers from India and international institutions have discovered that UBC 63, a star cluster previously thought to be a single unit, is actually composed of two distinct clusters. UBC 63, an open cluster approximately 4,892 light years away from Earth, was found to consist of UBC 63A and UBC 63B after analyzing data from the European Space Agency’s Gaia mission. The discovery, made by a DST INSPIRE Senior Research Fellow at Gauhati University and astronomers from the Indian Institute of Astrophysics, provides a rare opportunity to study the aftermath of a close flyby between two stellar systems. This encounter, which occurred about 6 million years ago, allowed the researchers to observe the dynamic evolution of star clusters within the Milky Way. The two clusters differ significantly in age, with UBC 63A being 21 million years old and UBC 63B around 562 million years old. The age discrepancy indicates that the two clusters did not originate as a single entity. By simulating their motions, the study found that the two clusters were about 60 parsecs apart when the younger cluster formed, and they came within 7 parsecs of each other roughly 6 million years ago. Today, the two clusters are approximately 26 parsecs apart and are no longer gravitationally bound to each other, moving in different directions.",
  "summary": "The astronomers, who set out to investigate star formation dynamics in the UBC 63 cluster using data from the European Space Agency’s (ESA) Gaia mission, were surprised to discover that UBC 63 actually consists of two clusters",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}