Panspermia: did life on Earth come from space? – Part 2, intentional panspermia & cosmic amino acids

Panspermia is the idea that life could have emerged on an alien planet, and then could have travelled through space to Earth, where it flourished and evolved into all the life we see today. So you, your family and your cat could all be aliens.

In the first post I looked at the idea that this alien life could have been simple bacteria, and could have travelled to Earth early in its history either in spores or in asteroids or comets. This is very much the ‘traditional view’ of panspermia.

In this post I’ll look at some alternative forms of panspermia, such as the idea that intelligent aliens may have deliberately seeded Earth with life.

Why the Universe may be full of life, but not intelligent life

In three previous posts (part 1, part 2 & part 3) I summarized the key highlights of the history of life on Earth, beginning with the Earth’s creation (hint, not by God), and ending with humans’ inventing the radio. I described the most important events, but I didn’t spend any time looking at their implications, particularly what this means for the search for alien life.

What can the history of life on Earth can tell us life on other planets?

Life on Earth: the highlights – Part 3

In parts 1 and 2 I looked at the key events in the history of life, from the birth of the Earth up to the evolution of the dinosaurs.

In part three I’ll continue from the dinosaurs right up to the appearance of humanity, and its finest work, Ellen Page.

As with the previous posts I’ll give approximate times for each event millions of years and I’ll use the label Ma for millions (mega-annum). I’ll also show the time in terms of a 24-hour clock. The last event I looked at was 225 million years ago, or 22:49 on the 24-hour clock. The next event is…