Last update: 29 July 2012

A Few 'Facts' to Whet the Appetite

... hopefully.

Pre-amble - why 'Facts' is in quotes: Science doesn't really 'know' anything. Observations lead to theories which lead to predictions which lead to more observations which lead to refinements or radical overhauls of the theories which lead to theories being broadly accepted but still subject to being proved wrong or only approximations or only valid in certain circumstances (there won't be any longer sentences!). Despite this it's an incredibly impressive process - we apply the theories to build phones, medical scanners, nuclear power, satellites, bombs, .... Point of this is that some of the things below we are pretty confident are close to being correct (the close being why I keep saying 'roughly' or 'approximately'),and others we are less confident on the accuracy or sometimes the broader truth. Plus I haven't tried to explain the basis of any of these yet, so you should retain a healthy scepticism. Anyway ...

1. The anti-clockwise direction of rotation assumes the observer is looking down on the Earth from above the North Pole.

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