Washington, Dec 21: Way back in 1755, the nebular hypothesis by Immanuel kant showed that our solar system is 4.6 billion years old, but if the US researchers are to be believed, the process of planet formation started exactly 4, 568 million years ago.
Researchers from the University of California Davis have shown that planets in the solar system started forming 4 ,568 million years ago -- when microscopic interstellar dust united into mountain-sized chunks of rock within a range of about 2,080,000 years. They established the dates by analysing a particular type of meteorite, called a carbonaceous chondrite, which represents the oldest material left over from the formation of the solar system, the Science Daily reported.
The physics and timing of this first stage of planet formation are not well understood, one of the researchers Dr Qing-zhu Yin, said.
So, putting time constraints on the process should help guide the physical models that could be used to explain it.
In the second stage, mountain-sized masses grew quickly into about 20 Mars-sized planets and, in the third and final stage, these small planets smashed into each other in a series of giant collisions that left the planets we know today. The dates of those stages are well established.
The researchers estimated the timing of the formation of the carbonaceous chondrites at 4,568 million years ago, ranging from 910,000 years before that date to 1,170,000 years later.
''We've captured a moment in history when this material got packed together,'' Dr Yin said.