~4.6 billion years agoReputable source · 2 sourcesWell documented
The Sun and Earth form
On the timeline · around ~4.6 billion years ago · Geologic
What happened
The Solar System condensed from a collapsing cloud of gas and dust; Earth accreted about 4.54 billion years ago.
Why it matters
Earth and the planets originate — the stage for all of geologic and biological history.
How we know
Radiometric dating of the oldest meteorites and lunar rocks pins the Solar System's age near 4.6 billion years.
Sources
- USGS. How old is Earth? · Reputable source
- NASA Science. Our Solar System · Reputable source