“How did they get here?”
“Well, it wasn’t extraterrestrially or through evolution.”
False conclusions, extraterrestrial and evolutionary origin on the Earth are both possible.
“The Late Heavy Bombardment subsided c. 3.85 billion years ago and scientists have evidence of life at 3.84 b.y.a. Interplanetary travel (”astrobiology”) is practically impossible,...”
Far from being impossible, the development of precursor organic biochemical chains is fairly common in nebulae, and evolution of these organic compounds is to be expected given the high energy physics that destroys and creates these biochemical chains.
“and the very short time interval above, just 10 million years, rules out evolution.”
That is false and nonsensical. The organic chemistry seed may have originated in the interstellar nebulae; on a previous planetary body billions of years older than the Sun, Solar System, and Earth; or on the Earth prior to the Late Heavy Bombardment.
“Therefore, by far the likeliest explanation is God as Creator.”
Presuming the Biblical story of Genesis is reflected in the observed existence of the Universe today, the God created Life by the evolution of the entire Universe, which would mean God is the Creator anyway.
Good post.