The Orgueil meteorite crashed into France 150 years ago. It's over 4.5 billion years old...and it might carry a piece of an ancient supernova that was instrumental to the solar system's birth.


Since the 1970s, astronomers have hypothesized that a supernova explosion might have released some of the crucial materials needed to form our Sun - this ancient star would, in essence, be the father of our current star. The existence of such a supernova would help explain why certain elements, such as chromium-54, are unevenly distributed throughout the current solar system. The chemical compositions of extremely ancient meteorites like the Orgueil rock carries microscopic records of the supernova's own chemical makeup, and so they can help reveal what this ancient supernova was like.

Two short-lived isotopes, aluminum-26 and iron-60, were found inside the Orgueil rock and are strong indicators of supernova origins. In particular, they likely came from a Type II supernova, which is when a massive star collapses and explodes. But it's also possible our Sun's "father" was a Type Ia supernova, where a white dwarf star in a binary system becomes overstuffed and explodes.


Further tests of the meteorite should reveal which kind of supernova preceded the birth of our solar system. Cosmochemists are particularly interested in measuring the levels of calcium-48 in the Orgueil meteorite. Calcium-48 is extremely common in Type Ia supernovas but almost unheard of in Type II supernovas. The analysis of calcium-48 should reveal which sort of supernova helped create our solar system, which basically means we're conducting the cosmic equivalent of a paternity test.

[Astrophysical Journal]