Astrobiology: The Joy of Being Wrong
An astrobiologist looks forward to the day when everything he says is totally wrong.
What makes a planet habitable? In a BBC News article, astrobiologist Christopher Watson (Queen’s University, Belfast) piles on the constraints:
- “Clouds are reflective and therefore will cool the planet, acting to push the habitable zone closer to the star.
- Just to complicate matters, the habitable zone also depends on the type of star the planet orbits.
- Red dwarfs like to chuck out large flares, stellar eruptions that release charged particles and X-rays. Given the close proximity of the planet, this might cause substantial atmospheric losses.
- High doses of radiation also tend to be harmful to biological material, and X-rays are capable of dissociating water – thereby depleting any water supply.
- Massive, hot stars are real gas-guzzlers. Yes, they may have far larger “fuel tanks” (they have a lot more mass to “burn”), but they gobble that fuel much, much faster, and die much younger than small, frugal cool stars.
- Based on our knowledge of how life evolved on Earth, it is unlikely that even simple life would have time to evolve around stars that are all that much hotter than our Sun.
- Well, we hit another issue – the fact that the variance in the amount of energy red dwarfs emit over their lifetime, known as their luminosity evolution, is quite drastic… a red dwarf may change its luminosity 10-fold!
- I haven’t even begun discussing some of the ‘rare-Earth’ arguments that point out a range of factors that affect the Earth that may be necessary for life, but that may be rare for other planets.
- These are things like the presence of Jupiter (which may or may not deflect asteroids and comets from striking the Earth)…
- or the presence of the moon (which may stabilise Earth’s spin).”
Watson isn’t trying to be a spoil-sport; just a realist. But how realistic is his ending conundrum?
The pace of discovery is astonishing and in 20 years’ time I suspect I will look back at this article and find I was totally wrong about everything.
This is what progress is.
That’s an odd way to define progress. It follows that 20 years after that, the ones who showed him he was wrong could be wrong themselves. An infinite regress looms.
We’ll help him out. He’s totally right about the constraints on habitability, but he’s totally wrong that life emerges on a habitable world without purpose, plan, and intelligence to act on matter and create it. We just saved him 20 years by reading Isaiah 45:18-19.