Astronomers have recalculated the timeline of events that shaped what was then the newly-formed earth -- and concluded it's about 100 million years younger than generally thought.

New research, led by planetary scientists at the Cote d'Azur Observatory in Nice, France, has revealed our planet's collision with another planet pretty much the size of Mars took place about 65 million years later than the scientific community believed, according to a report by The Australian..

The astronomical accident, the last of several colossal impacts in those formative years, actually ushered in the last step of Earth's formation by melting the future Blue Planet's rocky mantle. It also produced the debris that went on to form the moon. A 2012 analysis of titanium isotopes in Apollo Mission lunar samples showed that the Moon has the same composition as Earth

Scientists previously speculated the big crash could have taken as early as 30 million years after the solar system was formed, around 4,570 million years ago.

However, the latest study, published in the journal Nature, determined the run-in occurred between 26 million and 104 million years later. The data also discounted the chance of an an earlier collision with a "99.9 per cent confidence level," after comparing numerical simulations of Earth's growth and chemical composition.

So, according to John Chambers, an astronomer with the Carnegie Institution in Washington, D.C., the new paradigm dates Earth at 4,470 million years old.

It's important for researchers to know Earth's age because "it helps us understand how it formed and why it turned out the way it did," Chambers said in The Australian article. "This gives us hope that one day we will know roughly when the oceans and continents formed and when life first appeared."

He said the earth's construction took about 100 million years, while the asteroids, Mars, Jupiter and Saturn formed in just a few million years.