Much faster than previously thought:
The precursor of our planet, the proto-Earth, formed within a time span of approximately five million years, shows a new study from the Centre for Star and Planet Formation (StarPlan) at the Globe Institute at the University of Copenhagen.
On an astronomical scale, this is extremely fast, the researchers explain.
If you compare the solar system’s estimated 4.6 billion years of existence with a 24-hour period, the new results indicate that the proto-Earth formed in what corresponds to about a minute and a half.
Thus, the results from StarPlan break with the traditional theory that the proto-Earth formed by random collisions between larger and larger planetary bodies throughout several tens of millions of years — equivalent to about 5-15 minutes out of the above-mentioned fictional 24 hours of formation.
Instead, the new results support a more recent, alternative theory about the formation of planets through the accretion of cosmic dust.University of Copenhagen, “Earth formed much faster than previously thought, new study shows” at ScienceDaily
Paper. (open access)
Nothing seems to happen slower than previously thought. And the random collisions aren’t even in this version.