Oh, poor Creationists.
One of their favorite claims is that we live on a Privileged Planet that is just right for us. Thus magic man done it.
Unfortunately, science keeps coming along and showing that our egos are misplaced. We're special, but not magically so. We evolved big brains capable of deep thought, but it shares a common ancestor with all life.
Even our planet is a pale blue dot in a vast and inspiring universe. But Creationists constantly try to claim that this solitary orb is so amazingly perfect that it must have been made that way.
But even this claim is contradicted by the evidence. A new paper on arXiv takes a look at just how habitable planets similar to Earth can be.
The authors modeled Earth clones and varied numerous components of the system from the amount of ocean, to the eccentricity of the orbit, to the spin rate of the planet and looked to see just how far they could push them before the planet either froze into a snowball or became prohibitively hot.
Oh, the poor creationists. Their "privileged" prediction fails (not that this is surprising since previous work of Kasting et al. (1993) have shown the "habitable zone" is at least 0.95 to 1.37 AU).
The new paper suggests that eccentricity isn't an overly prohibitive constraint for planets. This is good since "40% [of exoplanets with measure eccentricities] are on more eccentric orbits than Pluto (e = 0:2488) and ~10% are on orbits with eccentricities >0.5." Surprisingly, for "planets with eccentricity 0.5... [the] greatest habitable semimajor axis can vary by more than 0.8 AU (78%!)"
This would be like Earth moving in as close as Venus and as far as Mars every orbit! According to Creationists this would be certain doom! Shame on reality for spoiling all the fun.
Ultimately, the most important factor of all the ones they simulated was the amount of ocean. Thanks to the high specific heat of water, it moderates the temperature even under large changes in eccentricity.
Regardless, the Creationist claim that Earth is so perfect for life just took another blow.
Perhaps one day the Creationists will actually notice.