A fireball explodes in the sky near Murchison, Victoria, Australia, in 1969. A total of 100 kg (220 lb) of meteorite fragments were found in an area of more than 13 kilometers (5 square miles). Thanks to the vast amount of exotic space rocks recovered, scientists have conducted extensive research on them and come to some incredible conclusions. Tiny particles isolated from meteorites, for example, have been found to be 5 to 7 billion years old, meaning they predate The Earth, the Sun, and even the solar system itself.
(Photo from NASA-JPL, via New Atlas)
Last year, studies suggested that the Murchison meteorite contained the extraterrestrial substances (sugars) that life was necessary to survive. Now, new research suggests it contains samples of the oldest substance found on Earth.
About 30 years ago, rocks were found to contain small silicon carbide particles that were older than the sun’s history. But until now, these “pre-solar particles” have been identified as exact ages.
To find out, the researchers measured the time when the “pre-solar particles” in meteorites were exposed to cosmic rays. These high-energy particles fly through space and can pass through solids and produce new elements in existing minerals that interact with them.
This means that scientists can measure the content of the new elements to determine how long they have floated in space to determine their final age.
(Study drawing: SiC scan scan image)
Based on this, the team found that most “pre-solar particles” range in age from 46 to 49 years. By contrast, our sun is still young (about 4.6 billion years old) and the Earth didn’t form until 4.5 billion years ago.
Amazingly, the oldest particle in the Murchison meteorite dates back more than 5.5 billion years, making it the oldest known substance on Earth.
The researchers point out that these substances may date back to the star that gave birth 7 billion years ago. This discovery suggests that the Milky Way, in which we are located, experienced a period of intense star formation during this time.
Of course, scientists have previously found other “pre-solar particles”, such as Hypatia Stone and LAP-149, but unfortunately their ages cannot be determined.
Details of the new study have been published in the recently published Proceedings of the National Academy of Sciences (PNAS), originally titled:
Lifetimes of interstellar dust from the cosmic ray exposure sit of presolar silicon carbide