I find that tenuous (like most of what Hawking says when he talks about things outside the realm of theoretical physics). It could be that complex life requires a relatively stable chemical environment, but abiogenesis requires an active chemical environment. In which case, finding ourselves on a planet where life emerged around the beginning is just the anthropic principle at work. It's very hard to make objective judgements about life when we've only got one data point. In fact it wouldn't even be particularly true what he's saying even if we assume a linear probability distribution through time of the emergence of life; we only know it emerged during the first 20% or so, which probabilistically changes very little at all. Certainly it's not enough to draw a conclusion from.
I can't wait for Europa either... it would be such a huge moment for mankind, and although it wouldn't be a surprise to any of us, it would give a huge boost to rationalism and humanism. The fact Europa would be geologically active is a very good sign, bearing in mind the very novel life forms (quite possibly the first life forms) we find around hydrothermal vents on Earth. I believe there's supposed to be a mission around 2020, but I don't know the details. I watched a documentary once about how they could use a probe with a heated metal nose to melt a tunnel through the ice under the force of gravity, which'd seal back up after it.
|
|
Bookmarks