Phoenix Arrives On Mars Sunday Night

On Sunday night, if all goes well, another NASA probe will land on Mars, bringing the number of active craft on the planet or in orbit up to 6. The Phoenix mission is different in that it will land near Mars' north pole. In 2002, the Mars Odyssey Orbiter mission discovered water-ice buried beneath the surface. Given that Mars' past was much wetter than it is today, did life ever arise there? Is there life there now? Phoenix will try to answer these and other questions.

Of course, there are some that already believe that there is life on Mars. I'm not referring to the Face of Mars, but more "mundane" discoveries. ALH84001, a meteorite whose origin was traced back to Mars, contains chain-like structure that could be the remnants of fossilized bacteria. Although tests for organic material have revealed amino acids and polycyclic aromatic hydrocarbons (PAH). However, the results aren't conclusive. There's still the possibility that non-biological processes could be involved or the meteorite was contaminated from contact with Antarctic ice.

But the life on Mars debate goes back even further. When the Viking probes landed on Mars, soil samples were tested for the presence of organic materials. Basically, the soil was dumped into solutions of water and nutrients. The amount of CO₂ in the test chamber increased. The onboard gas chromatograph (GC) didn't detect any sign of organics but Gilbert Levin, the experiment's designer, said that the amount of microbes could've been below the threshold detection limits of the GC. Others counter that superoxidants in the soil could've produced the observed reaction. A recent re-examination of the Viking data suggests that extremophiles, a form of life unknown during the 70's, might account for the observed results.

Phoenix will try to settle the matter once and for all. But while there are a lot of us that hope it discovers signs of life, past or present, there are those who hope it doesn't. Nick Bostrum wrote an essay for MIT's Technology Review (TotH: David Brin) explaining why he hopes that Phoenix doesn't find anything. For those of you not interested in registering or reading the lengthy article, I'll summarize it.

The foundation of Bostrum's piece is Fermi's Paradox. To paraphrase, considering the age of the universe and assuming the existence of life is at least somewhat commonplace, where is everybody? We should've been contacted by someone by now. UFO sightings and alleged abductions notwithstanding, we don't have any evidence that intelligent life exists outside of Earth. For the sake of his piece, Bostrum doesn't show any interest in the positive explanations (I define "positive" to mean "yes they exist, but....") that are offered in Wiki. Instead, he sticks with the negative explanations.

Bostrum has labeled the event that has thus rendered us alone "The Big Filter." What is The Big Filter? The Big Filter is some event that wipes out life everywhere in the cosmos and has left us in our current situation: all alone. He doesn't know what it is exactly, but it results in any of the negative explanations in the Wiki entry. The Big Filter either occurs in the distant past, inhibiting life from arising in the first place, or at some point in the future, destroying civilizations before they can expand beyond their homeworld.

If Phoenix doesn't find any signs of current or past life (expected to be microbial), then it means Earth, and humanity, has survived its encounter with The Big Filter and is free to prosper in the galaxy.

If Phoenix does find life, or signs of past life, on Mars, then the universe has the natural propensity to create life, but, in keeping with Fermi's Paradox, it doesn't survive long enough to spread. That means that Earth and humanity still has to face the challenge of The Big Filter and there's no reason to believe that we are any different than any other civilization that has come before us. Whether civilizations self-destruct, or run out of resources before they escape the confines of their homeworlds, or are eradicated by some external threat, the odds are against us and we're doomed.

Of course, there's no guarantee that if the The Big Filter lies in the past, we won't go extinct anyway. Unless we can strike a balance between aggression and compassion, wisdom and folly, intelligence and ignorance, enlightenment and fear, then the universe is probably better off without us.

\_/
DED