Moon not only attracts the water. Gravity does not distinguish well as land, sea and air travel following the moon. Such We may not realize it but what does a fish at the bottom of the ocean tides?
Let's start by explaining the subject of the tides. If the Earth did not have satellite would be a more or less stable area, an earthquake here, a detachment there, but no major changes every few hours. The presence of the Moon, its gravity, it attracts whatever is on our planet change this situation. And as the force of gravity depends on the distance more strongly attracted to objects closer, those found in front of his face.
forces on variables from the Moon, (sometimes aided by the Sun) the surface is deformed by creating two bumps on the ends. The rigidity of the crust deformation limits but the ground can rise 30 to 50 centimeters .
do not see it because we have no references to perceive the change. The case of water is different. We have a reference since the lower ground displacement allows us to measure the rising tide. This rise depends on several factors. First the distance to the moon, which varies between 363,104 and 405,696 miles. Second orientation to the sun, which can add the effect and, last but not least, local geography that can enhance or diminish much height. In general, costs ocean tides are much higher than for smaller seas.
And the atmosphere? It also moves but here we have even less references. Like a fish in the background we study the surface problems. What we can do is to measure changes in pressure caused a wave. The effect is very small, just 100 microbars
, about 0.01 percent of the normal pressure on the surface. Compared the change in pressure at the bottom of the ocean can be from 0.1 or 0.2 percent. In both cases, the change is completely hidden from the variations caused by weather and only careful statistical analysis can discover. Even the thermal expansion caused by the sun at dawn, generates a pressure change 20 times more intense in the atmosphere
But although the results are different from the cause is the same. The moon draws us all and all alike. Sometimes as much as to dream of visiting.
Category: Physical
