Milky Way Star Formation Burst Recorded in Presolar Grains
c. 6.8 Billion years ago · Prehistoric
Approximately 7 billion years ago, the Milky Way experienced an episode of significantly elevated star formation. Evidence for this burst comes from presolar silicon carbide grains extracted from the Murchison meteorite, which fell in Australia in 1969. Cosmic ray exposure dating of 40 individual grains revealed a statistically significant clustering of ages around 7 billion years, indicating a period when many stars formed and later shed material into interstellar space. These grains represent the earliest known solid material found on Earth, predating the solar system by billions of years and providing direct physical samples of pre-solar galactic conditions.
Topics
Milky Waymeteoritesstellar formationgalactic archaeologypresolar grains
Connected Events — 4 Connections
Stars formed during this burst shed material into interstellar space that contributed to the molecular cloud from which the Sun condensed approximately 2.4 billion years later Formation of the Sun
The star formation burst occurred billions of years after globular clusters like HP 1 had formed, representing a later phase of sustained star birth in the Milky Way disk rather than the bulge Formation of Globular Cluster HP 1 in the Milky Way Bulge
The burst represents a period of elevated star formation within the Milky Way, contributing to the galaxy's stellar mass growth Formation of Milky Way Galaxy
The merger triggered waves of star formation in the Milky Way disk, contributing to the elevated star-forming period recorded in presolar grains Gaia-Enceladus Dwarf Galaxy Merges with the Milky Way
The Time Detectives® · Cadet Mission
Investigate This Event
Place it on the timeline. Earn points. Master the connections.
New to The Time Detectives?
Learn what it is →