IN THE film Avatar, the blue-skinned Na’vi inhabit the lush moon of a gas-giant planet. What would life be like if Earth were such a moon? Neil Comins investigates this possibility, along with nine other tweaks that might make our cosmic neighbourhood subtly – or fundamentally – different. What if the moon orbited Earth backwards? What if our solar system were located in the centre of our galaxy, rather than in the suburbs?
Counterfactual science is not everyone’s cup of tea, but the author’s pedigree as an astronomer at the University of Maine ensures the physics is rock-solid in this, his second…
