John Hodgman is a very strange and funny man. You may know him as PC, in the Mac and PC ads. Or as the resident expert on The Daily Show. But it’s a surprise to discover that he’s an expert on extraterrestrial intelligence.
He explains that physicist Enrico Fermi shocked his colleagues by meeting them for lunch and asking, “Where is everybody?” This was a bit odd, as everyone was there for lunch. But Fermi meant, “Where were the space aliens?” Fermi went on to disprove faries, the sasquatch and the possibility of love. “As you know, after that, Enrico Fermi ate alone.”
Hodgman believes Fermi is wrong… and that, perhaps Fermi was an alien. “Isn’t it a little strange that Fermi wanted no payment for his work, just two healthy sperm whales. That’s not true.” But wouldn’t Fermi be the first to try to convince his fellow scientists that the aliens aren’t already here.
He offers three experiences from his past that prove the existence of aliens. They involve an odd conversation on a boardwalk at a beach resort, a conversation with a girl during the film “Dune” and the time his girlfriend, now his wife, went alone to a beach in Portugal, and turned up after he’d been befriended by five Liberians. He believes she’s been replaced by an alien robot, but he loves her anyway.
Like I said, he’s very strange and very funny. Don’t ask me to explain any further.
Palentologist Peter Ward, one of the authors of “Rare Earth” is left to debate Hodgman. He explains the danger of doing this: “You cannot take people’s aliens away from them and expect to be anyone’s friend.” Individual people want to believe in aliens, and projects like SETI really want to believe in intelligent life in our galaxy.
But Ward believes “a good world is hard to find.” Some worlds are beter than others – Mars isn’t so bad, and we can exist there with protection. Venus is a bad deal – it’s what happens with runaway greenhouse effects. We might expect to see a similar pattern with our planet. The “biotic death of old age” will likely come after a second microbal age – our brief moment, the age of animals, is a short golden age. Eventually, the planet will be consumed in the explosion of the sun. That is, unless we die in an accident.
Planetary accidents involve being affected by a distant supernova, or being hit by a passing body. He shows an image of the Fish Clay in Stevns Klint – it shows a boundary between a layer of chalk and one of black stone. Between the two is a thin red layer, filled with Irridium and with “shock quartz”, a mineral that forms under great pressure. The chalk is a layer created by the decay of plant material. The black layer above it is a layer of seafloor without plankton. This is evidence of mass extinction – the KT extinction – which reduced the world back to a biotic state.
Ward tells us that there are at least five mass extinctions blamed on large body impacts. Scientists now study “impact tracers”, molecules like c60 (buckyballs) or Helium 3, which are common in space, but much less common on the earth. Studying the extinction between the Triassic and Permian periods in the South African fossil record, Ward has been focused on what species survived. Reptiles tend to do okay; warm-blooded animals take a huge hit. After this sort of extinction, the Triassic began with a reptile universe, a world of crocodillians.
He tells us that “Gaia theory is rubbish” – the idea that the world makes things better for itself is unsupportable. “Life does try to do itself in.” The weapon of choice, he argues, is hydrogen sulfide. It’s very fatal to humans, deadly in 200 parts per million. You can find it emitted by volcanos and by vents deep in oceans. In the Black Sea, it’s possible to pull up ocean water that’s a shade of pink-purple. That water is water rich in hydrogen sulfide. There’s a huge set of bacteria that can survive on sunlight, in hydrogen sulfide rich environments. Those are the bacteria who may take over, if we’re not careful.
Lee Kump at Penn State believes that mass extinctions are caused by lowering oxegyn levels, raising carbon dioxide levels and producing H2S from the oceans. If the CO2 level increases we’re currently seeing, we can expect a level of 1000 PPM of CO2 within hundreds of years – that level will cause a release of huge levels of H2S, causing our extinction through the rise of purple oceans.
Freezing mice… for SCIENCE!
There’s a fascinating biological trick associated with hydrogren sulfide. If you are severely injured far from medical care, it may be possible to have you breathe a solution of 80ppm of hydrogen sulfide and chill your body. This appears to trigger a reaction in mammals which, basically, helps us revert to a reptilian state. A colleague of his has been chilling mice under these conditions for up to four hours – he’s able to revive them afterwards. It’s not a perfect technique – humans will likely experience brain damage being chilled like this, but it’s a potentially life-saving emergency technology.
(It wasn’t entirely clear to me whether this effect of hydrogen sulfide made the case that there’s something in mammalian physiology designed to help us survive H2S extinction events… or whether reptiles can survive in a H2S environment. But it was a fascinating talk, and I’m looking forward to reading more of Ward’s work.)