Velcroman1 writes "Ever wonder why the red planet is red?
About 180 million years ago, a planet-shattering yet naturally occurring nuclear reaction may have wiped out everything on Mars, sending a shockwave that turned the planet into dry sand.
Even more incredible: A natural nuclear reaction could have occurred on our own planet — and could happen again, said Dr. John Brandenburg, a senior propulsion scientist at Orbital Technologies Corp.
"The Martian surface is covered with a thin layer of radioactive substances including uranium, thorium and radioactive potassium — and this pattern radiates from a hot spot [on Mars],” Brandenburg said."
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