Three Most Commonly Asked Questions About Eclipses

What happens more often, solar or lunar eclipses?According to Fred Whipple’s book Earth, Moon and Planets, solar eclipses are fairly numerous, about 2-5 per year, but the area on the ground covered by totality is only a few miles wide. In any given location on Earth, a total eclipse happens only once every 360 years. Eclipses of the Moon by the Earth’s shadow are actually less numerous than solar eclipses; however, each eclipse covers about one half the surface of the Earth. At any given location, you can have up to three lunar eclipses per year, but some years there may be none. In any one calendar year, the maximum number of eclipses is four solar and three lunar.Typically, how big a temperature drop do you get during a total solar eclipse?It would probably be equal to the typical daytime minus nighttime temperature difference at that time of year and location on the Earth. It would be modified a bit by the fact that it only lasts a few minutes, which means the environment would not have had much time to thermally respond to its lowest temperature, so it would probably only be 3/4 or 1/2 the maximum day-night temperature difference. Because the patch of the shadow travels faster than the speed of sound, weather systems will only be affected very locally directly under the instantaneous footprint of the eclipse. The main effect is in the “radiant heating” component which goes away suddenly at the moment of eclipse and produces a very fast temperature decrease. If the wind is blowing, your body probably exaggerates, by evaporative cooling, how large the actual temperature swing actually is.Do lunar and solar eclipses have any noticeable effect on humans?There is no evidence that eclipses have any physical effect on humans. However, eclipses have always been capable of producing profound psychological effects. For millennia, solar eclipses have been interpreted as portents of doom by virtually every known civilization. These have stimulated responses that run the gamut from human sacrifices to feelings of awe and bewilderment. Although there are no direct physical effects involving known forces, the consequences of the induced human psychological states have led to physical effects.