Natural nuclear reactions?!

So I’ve been reading all over the internet today about how “natural nuclear reactions” could have caused Mars to be red (see: any news site, or just here for the jist of it: http://www.foxnews.com/scitech/2011/04/01/natural-nuclear-blast-mars/ [don’t judge me, I hate Fox, it was just the first hit I got ;-)]), yet, when I google the phrase “natural nuclear reaction”, I got no such hits. Or anything like it. Which means one of two things: Google is conspiring against laws of physics, or this idea is unique to the individual’s hypothesis. Honestly, I feel like I may have heard of such a thing before, but seeing as I can’t get any sources supporting it, I have no idea what the eff a natural nuclear reaction is!!! Could anyone explain this idea to me? Not even necessarily one that could destroy a planet, just what it is, and the circumstances that need to happen in order for it to be called into existence! Thanks!

Here you go.

The only requirement for a “natural” nuclear reaction is the proximity of the correct isotope of Uranium. There is no longer sufficient concentration of U-235 in any one place for such a reaction to exist (which is why reactor fuel must be enriched for use in power plants), but there was at one time.

I actually remember hearing about this in science class back in the late 70s - I always thought it was very interesting=)

This article sounds like nonsnse to me. Natural nuclear reactors do exist, where geological processes have concentrated radioactive isotopes. However, the idea of this producing a large nuclear explosion seems absurd to me. It takes a special set of circumstances to trigger a nuclear fission explosion. You need highly refined materials, and a critical mass needs to be formed in a very short period of time. Otherwise, you get a fizzle, the energy of the reaction disperses the material before much of it has a chance to react.

It also has nothing to do with Mars’ colouration. It’s red because much of the surface is covered with iron oxide dust.

A ‘million megaton’ blast, the article says. That could not possibly be a natural nuclear blast - it’s far too large - and natural thermonuclear blasts are called novae and supernovae and are confined to stars. And are orders of magnitude more powerful. A million megaton blast would be the result of a meteor impact.

This article explains it in detail:

It ‘operated’ for 150 million years at a average power of 100kW. That is Pretty Amazing.

That’s the Oklo reactor, not this alleged blast on Mars.

See, that’s what I thought too… I dunno, I’ve heard of natural nuclear reactions but it just seemed a little strange that ones that powerful could happen. That and I always thought it was the iron oxide dust that caused the coloration too. Oh well, just another theory to add to the growing fodder of ideas. Not trying to put anything or anyone down, but I think sometimes the answers are far more simpler than we choose to believe. Everyone knows that Mars is barren because ancient civilizations raped and pillaged the land… then blew themselves away :wink: