A huge meteor?.......................
A huge meteor?
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An asteroid which becomes a meteor when it enters Earth’s atmosphere.
or as someone else (astronomer Tom Van Flandern), posited there were two planets that exploded: one was about that date; this explosion stripped Saturn of its moons (the Saturn Myth) - the Earth and Mars being two of them.
The explosions also changed the solar system configurations driving the gas giants from the inner solar system to the outer. That is the configuration found in all solar systems discovered to date; our solar system is an outlier.
During the orbital and positional change, the Earth would have been wandering (the period of Snowball Earth) until it reached the ‘habitable’ zone.
All that aside, no one knows what the solar system configuration was half a billion years ago - its all conjecture and guesstimates.
The only thing known now is that the solar system configuration is not normal.