Seti or Weti?

Today I listed to one of my favorite podcasts, Astronomy Cast episode 110 "The search for extraterrestrial intelligence" where good buddy Fraser Cain and the lovely Pamela Gay (yes, I am a fan of Pamela's) talk about Seti (the Search for extraterrestrial intelligence) and the possibility of finding extraterrestrial life via catching their "stray" radio or tv broadcasts.

Seti has been going on since the 60s and still has not shown any "alien" signals. That does not mean they are not there as every good skeptic knows that "absence of evidence is not evidence of absence" but its apparent lack of success has not necessarily contributed to being a well funded endeavour, which I think is a shame.

Success or lack of it aside, the idea of extraterrestrial life is most intriguing. Basis the premise that the Universe is a very large place and that Earth is basically insignificant against the gigantic backdrop of what we know exists, extraterrestrial life looks like a logical conclusion - if life happened on Earth it must have happened elsewhere, once we also accept the fact that there may be nothing particularly especial about Earth, the sun and the human race in general. Life may be rare but that doesn't necessarily make it unique.

But if life is not unique to Earth, does that mean we will meet an extraterrestrial civilization? No one really knows as the progression of events leading to contact between two separate civilizations may indeed make such contact very improbable if not impossible:
  • Right conditions for life must exist
  • Life must arise and evolve
  • Evolution must lead to intelligence
  • Intelligent life forms must develop technology
  • This tecnology must allow for interstellar travel or communication of some sort
  • The communication capability must exist for a finite amount of time

Each one of the above must be a very low probability event. These probabilities, taken together, offer an insight into a possible number of "communicative" civilizations. Dr. Frank Drake developed Drake's equation, in 1961 (read more about it at the Seti website). As solved by Frank Drake himself, the equation yields a number of 10,000 "communicative" civilizations in our galaxy.

The last term in Drake's equation refers to the lifetime of this "communicative" civilization. I haven't heard or read anything about this particular term but I have indeed thought about it.

Our sun seems to be a third generation star as it contains a lot of heavy elements (heavier than iron) same as the solar system. Without these elements, life as we know it could not have evolved.

Considering that the lifetime of a star like the sun may be 8 to 10 billion years, we seem to be indeed early in the "history" of the universe. That would present an argument for saying that we may be among the first technologically capable civilizations in the galaxy and that we may be, eventually, the first or one of the first to venture out into the unknown.

On the other hand, there was a huge meteor impact on Earth about 65 million years ago, that nearly wiped out all life on the planet and led to the disappearance of the dinosaurs or at least that is the generally accepted view. But I keep wondering if species of dinosaurs like velociraptor could not have evolved into sentient, intelligent beings much like humans but with a 65 million year head start?

Actually there is a Star Trek Voyager episode which depicts descendants of dinosaurs that escaped destruction on Earth and now living on the Delta quadrant of our Galaxy, wherever that is (Season 3 episode 23 "Distant Origin") . Obviously this is highly especulative but so is Star Trek. These intelligent reptiles are the kind of advanced civilization that a 65 million head start on us would lead to.

So, if that 5-6 mile piece of space junk had not hit, we might all be dinosaurs roaming the skies. And if other civilizations had that same kind of a head start, we are late to the party. Probably too late.

After all this ranting, what is it going to be? Seti... or should we wait and see? That is what WETI stands for, Waiting for Extra Terrestrial Intelligence to arrive.

Me, I am sitting back and relaxing waiting to see if our velociraptor cousins show up. Good piece of advice from Pamela.

Listen to the podcast. You will be enlightened while being entertained.

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