London: A meteor discovered in the Saharan desert has indicated that the age of our Solar system is much older than previously thought.
Analyses of the meteorite indicate that the Solar system is at least 0.3–1.9 million years older than some previous studies projected – making it 4.568 billion years old.
The small difference means that the gas and dust that gave rise to the Solar System should have around double the amount of a certain iron isotope, iron-60, than previously suggested.
"This suggests that one or more supernovae happened before the Sun`s formation, explaining all these elements and their respective abundances," Nature quoted Audrey Bouvier from the University of Arizona in Tempe, as saying.
The analysis involves comparing the ratio between two isotopes of lead (Pb), lead-207 and lead-206.
The iron abundances discovered in meteorites bolsters the case that our Solar system grew up surrounded by giant, heavy stars and was shaped by their activities.
Before the Solar system existed, massive stars lived within a cloud of gas and dust. These stars emitted huge amounts of ultraviolet light, whose photons exert a pressure that pushed outward in a sphere, carving out a cavity from the nebular gas and dust.
As this cavity expanded, its edge squeezed together the surrounding debris – increasing its density and mass, which in turn attracted more particles because of an increased gravitational pull.
This led to a snowball effect of accumulation, creating protostar. The protostar lived within its own bubble of gas and dust, creating an evaporating gaseous globule`` or EGG. When the massive stars exploded as supernovae, they sent an element-rich rain to rapidly mix with the materials inside the EGG.
After millions of years, our Solar System coalesced from the rocky grains and asteroids now saturated with supernovae iron.
"This research points to the fact that there are more materials out there to study, which means there are more secrets to uncover," said planetary scientist David Kring.