From a slightly different standpoint, this sounds like a combination of these two stories:
“The Windows of Heaven” by John Brunner – during a solo moon landing, an abnormal solar flare destroys all life on earth, leaving the astronaut the sole survivor. He returns to Earth and
releases the bacteria in his spacecraft into the atmosphere to repopulate the planet.
and:
James Blish’s “Surface Tension” in which a terraforming party crashes onto an alien world without hope of rescue. Before they die they create tiny versions of themselves adapted to the new world, and leave them engraved metal plates as records of where they came from.
He puts the time of impact at just 50 million years after the initial formation of the earth, when it was just 90% of its current size, just beginning to get a core and just possibly covered by magma oceans from less violent hits. So no possibility of life at that time.
He also has an appendix in which he debunks the moon landing hoax conspiratists by noting that the rocks brought back from the moon could not possibly have made by any conceivable earth technology and that they correspond not to theories of the moon extant in the 1960s but to those conceived since the moon landing, an elegant one-two knockout punch.
The version I have appears in The Penguin Science Fiction Omnibus (edited by Brian Aldiss), which I think came out in 1973.
The Omnibus is apparently a compilation of three earlier Penguin sf anthologies, but I don’t know which of them the Brunner story would have appeared in.
The story itself dates from 1956, and is about 13 pages long.
Is ther age of the earth cross-referenced with other bodies in the solar system?
ie, is the following possible:
The earch is really 6-8 billion years old? Long enough the whole cycle of live we know today on earth, perhaps even leading up to intelligent life? But 4.3 billion years ago, an impact sterilization event occurs leaving the planet is a state very similar to how scientist believe earth formed the first time. All while leaving no trace of what ever was here previously, causing scientists to conclude that 4.3 billion years ago was the initial formatin of earth.
No, the sun is believed to be a little less than five billion years old, so it would have been mighty cold if Earth was here before then. But I agree with an earlier poster that given only a single instance of intelligent life having emerged, it’s hard to say with certainty whether our evolution time was short, long, or typical. But I think it unlikely that the time available before the moon-forming collision (if it occurred as theorized) would have been enough.
