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Showing posts with the label Earth's axis

The fascinating science of a terrible event

The ever-expanding catastrophe faced by Japan's people as a result of last week's earthquake (now rated as a 9.0 on the Richter scale), the tsunami that followed, and now the very real possibility of a nuclear disaster is almost too awful to imagine. No, in fact, it is too awful to imagine and, frankly, I am not sad that my imagination is not up to the task. All the reports about the events that I have seen or heard emphasize that Japan is about as well-prepared for disaster as any country can be. They are well-aware of the seismic neighborhood in which they live, and they expend every possible effort to make people knowledgable about what could happen and to get them ready for the eventuality. Even so, the devastation is terrible and the tasks people face in rebuilding their lives seem almost beyond human capabilities. It breaks the heart and stuns the mind. And yet, in spite of all that, if one can manage to step back for a moment from the human devastation and simply c...

The earth moves and its axis shifts

NASA scientists are now saying that the massive earthquake that hit Chile last Saturday (Corrected from "Thursday." What was I thinking?) was enough to actually shift Earth's axis by as much as three inches. I won't even pretend to really understand how this works. It has to do with the movement of rocks in the planet's core and the actual shifting of Earth's weight from one area to another. Sort of like, over time, a person's weight may shift to the center of his/her body, causing a personal axis shift. That's about as close to an explanation of the phenomenon as I can get. It turns out this is not an unusual occurrence. Whenever an earthquake of this magnitude occurs, it is likely to cause some wobbles in Earth's rotation and changes in the axis. JPL research scientist Richard Gross computed the changes that this particular earthquake caused. He estimates that it has shortened Earth's days by about 1.26 microseconds. A microsecond i...