The human species has been sending signals into outer space since Marconi's day. After all, once radio waves are out there, they just keep going. Marconi's first crude experiments, at his family estate in Italy, took place in the middle 1890s -- so, 130 years ago. Famously, less than 20 years later the radio operators of The Titanic stayed at their posts on that awful night in April 1912 tapping out Morse code distress signals. In principle, an extraterrestrial intelligence one hundred and fourteen light years away from us could even now be picking up on those signals. What do such beings make of them? Do they take them to be evidence that "we Fl'korgians are not alone!"? There is a rhythm to them -- those signals from The Titanic -- that likely seems an intelligent construction. Dot dot dot dash dash dash dot dot dot. Pause and repeat. Over and over. My guess is that if the Fl'korgians have technology powerful enough to pick up on that pattern at th...
Yesterday we asked when and how life on earth began. We didn't answer that question. We offered a scenario for a proto-life, but also noted that much more would have to happen for that to become cellular life as we generally understand the term. It is possible that life -- considered as something DISTINCT from the proto-life I discussed yesterday, had two origins. There were two paths forward, so to speak, bacteria and archaea. The bacteria developed first. Muh later, the archaea developed and absorbed the bacteria so the later became the energy producing part (the mitochondria) of larger cells. As to the timing? The best guess sets the early RNA replication (proto-life) at about 4 billion years ago. There were complicated cells, leaving a fossil record, by 3.5 billion years ago, so each of the two paths described above had been executed by then. IF any of this is right. Science proceeds by falsification, and this all may be falsif...