Slashdot Mirror
Blue, Not Red: Did Ancient Mars Look Like This?
astroengine writes "Using elevation data from NASA's Mars Reconnaissance Orbiter, software engineer Kevin Gill was inspired to create a virtual version of the red planet with a difference. 'I had been doing similar models of Earth and have seen attempts by others of showing life on Mars, so I figured I'd give it a go,' Gill told Discovery News. 'It was a good way to learn about the planet, be creative and improve the software I was rendering it in.' He included oceans, lakes, clouds and a biosphere — a view of a hypothetical ancient Mars that looks wonderfully like home."
So the typical Martian was one ugly motherfucker, then? "Ain't got time to bleed!"
Props for realizing that a Mars covered with water would be blue, too. Such insight!
This is where using 2-3 minutes to read the fine article would have helped you out.
It is a software guy who just wondered what it would look like with earthly features. This is not based on any kind of facts other than the elevations.
It is an interesting exercise.
But I notice the renderings show a lot of nicely circular lakes, suggesting meteor impact craters. If Mars at any time had this amount of water and a thicker atmosphere there would likely be less craters and those that did remain would probably have different shapes due to erosion. It would suggest the meteorite impacts happened after the water evaporated and the atmosphere thinned.
People seem to forget that after its formation the sun was somewhat LESS bright than it is now so Mars would have been even colder in its current orbit. If there ever was large amounts of water on Mars I suspect that it would have spent most of its time locked up as ice sheets with the occasional melting due to impacts. Pretty much the way it is today.
All this warm wet life on mars stuff strikes me as nothing more than wish fulfillment - the same way people used to imagine Venus was a tropical paradise. Until the probes went there and proved those predictions to be some of the worst ever made in astronomical science.
In Kim Stanley Robinson's Mars trilogy, the northern ocean is filled with fresh water from the molten polar ice cap, while the rivers take up salt from the rocks they flow over, so there are salty rivers flowing into a fresh water ocean. I'm not sure how realistic that is, but it doesn't seem completely illogical.
As artist impressions go, I prefer this one, by Daein Ballard over the one in the article.
I've been (very slowly) doing something a bit similar with the moon --- see here --- although differently; I've been trying to render everything and producing ground-level views rather than producing a painted sphere like TFA. (His looks better from a distance. Mine looks better close up.) I've been trying to use procedural texturing and atmospheric effects. The pictures above are rather out of date; rendering your own from SVN will look better.
Unfortunately rendering things the size of planets from very close up runs into big problems with floating point precision. The only renderer I've found which will do it at all is Povray, and even then there are loads of bugs --- volumetric effects for things like clouds is well buggered at this sort of scale. See this picture for an example. Plus Povray's is really slow at procedural surfaces.
Right now I really need to start again from scratch using higher-resolution terrain and gravity data from some of the recent lunar probes, and I also probably want to switch to a different renderer which works at higher precision. Any suggestions of a fast raytracer that does procedural isosurfaces, volumetric effects and works at double precision will be gratefully appreciated...
I will also share this test render with you, which I think is delightfully surreal...
It implies that somebody (perhaps the submitter?) thought that the simulation is intended to be accurate.
As parent says - read TFA, it's meant to be a creative exercise.
Also read Kevin Gill's own explaination.