Volcanoes - majestic and powerful creations of nature.They are acts and omissions there from early times to the present day, as if forcing mankind to "listen" to the changes taking place within the Earth.After all, I did not have time in world history the entire town was buried under a layer of volcanic ash and magma, and civilizations are doomed to perdition!Each volcano has a crater.This recess in the form of a funnel, which is located on the top or slope.
origin and structure
The word comes from the Greek "bowl, mixing vessel of wine and water."By analogy, a form of education is similar to the cup or funnel.Through it erupts magma inside the volcano.Crater - a natural formation, having a diameter from a few meters to several kilometers.His appointment - output of magma.In abeyance volcanoes crater - a kind of outlet for the accumulated output in the depths of gaseous mixtures.This education is provided by special ducts leading into the middle of the volcano and down to allow for the free eruption.In the "extinct" volcanoes ducts sometimes "overgrown" and the crater becomes rather decorative formation, sometimes used by people in ritual and other purposes.
The Moon
With the ability of mankind to explore the moon with the help of powerful telescopes, and realized her dream of closer consideration.It turned out that there are some craters.Lunar Crater - is, in fact, the mountain ring.This cup-shaped recess has a relatively flat bottom and is surrounded by annular shaft.According to modern science, almost all lunar craters have a "bump" in origin.That is, they are the result of mechanical action on the surface of the moon meteorites that fell mainly in the distant past.Only a fraction of the Earth's satellite craters are still some scientists believe the volcanic origin.
little history
known that Galileo first discovered the lunar formations using a telescope made by him (a small, approximately three-fold increase).He also has appropriated the name of the phenomenon - the crater.This determination is left to the scientific use, and to this day.But the opinions of scientists about the origin of craters radically changed: from the impact of cosmic ice and volcanic formation to "shock".Modern science to determine the accuracy of recent origin as a way of the vast majority of craters on the moon.By the way, we found similar formations on other planets of our system, such as Mars.
