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A green flash can occur at sunrise or sunset when some part of the Sun suddenly and briefly seems to change color from red or orange to green or blue. This is an optical effect caused by the larger refraction of light at the blue/ green end of the spectrum…

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Intriguingly, a similar mass extinction has ushered in the reign of the dinosaurs. Indeed, over the last 600 million years of life on earth, there seems to have been a cataclysmic change roughly every 60 to 70 million years, and smaller changes roughly every 30 million.

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What you want to know about a seismograph.

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Dirt can be a fascinating subject especially if you happen to be someone who likes to dig around in it, someone like a rock hound or a geologist or an archeologist or a nine year old boy. He likes dirt. He likes rocks and minerals and he is very glad his old grandmother isn’t quite as old as dirt and we still have a lot of outdoor adventure and rock hound ahead of us…read more.

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Why floods are so dangerous to people.

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This about earthquakes being caused by several things we do to destroy our own planet.

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The Sun has 11 –year cycles of sunspot activity due to changes in its magnetic field. The increased surface activity means that more changed solar particles reach Earth’s atmosphere, causing radio interference and aurora. Nuclear reactions in the Sun’s core send waves of energy flowing to the surface, where it is given off as light, heat and other radiation.The Sun’s diameter is 1,392,000 km (865,000 miles). More than one million Earths would fit inside the Sun.

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The five biggest volcanic eruptions in modern times spewed out more than 100 cu km of magma. One of these include the largest eruption in living memory.

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This amazing Cave of Crystals contains some of the largest known crystals in the world.