DRAGON'S EGG NEBULA (Syllabus GS Paper 3 – Sci and Tech)

News-CRUX-10     15th April 2024        

Context: Two large stars residing inside a spectacular cloud of gas and dust nicknamed the "Dragon's Egg" nebula have presented a puzzle to astronomers.

New Research Findings

  • Star Cannibalism Revealed: A recent study in Science suggests that a larger star devoured a smaller sibling, resulting in a merger that generated a magnetic field through the mixing of their materials.
  • Violent Stellar Merger: Astronomer of the study, indicates that the merger was likely turbulent, potentially ejecting material and forming the observed nebula.
  • Binary System Discovery: The two remaining stars, now a binary system, are situated approximately 3,700 light-years away in the Milky Way galaxy's Norma constellation, with a light-year representing about 9.5 trillion kilometers.
  • Stellar Characteristics: The magnetic star, 30 times more massive than the Sun, and its companion, 26.5 times more massive, orbit each other at varying distances, ranging from seven to 60 times the Earth-Sun distance.

Dragon's Egg Nebula

  • About: The Dragon's Egg nebula surrounds a pair of stars and is named after its proximity to the 'Fighting Dragons of Ara' nebula complex.
  • Birth of the Triple Star System: The stars within the Dragon's Egg nebula formed approximately 4-6 million years ago as a triple system, originating from the same stellar birth event.
  • Composition: The triple system comprised a larger star, possibly 25 to 30 times the mass of the Sun, and a smaller star, estimated to be five to 10 times the Sun's mass.
  • Evolution and Merger: The larger star evolved faster, leading to its outer layers engulfing the smaller star, culminating in a merger event that ejected gas and dust, forming the nebula.
  • Recent Cosmic Event: The merger event occurred relatively recently in cosmic terms, around 7,500 years ago, based on the expansion velocity of the nebular material.
  • Unusual Composition: The nebula primarily consists of hydrogen and helium but contains a notable amount of nitrogen, attributed to the merger event.
  • Magnetic Fields: Many stars similar in size to the Sun produce magnetic fields, contributing to the dynamics within the Dragon's Egg nebula.