The fact that in the solar system between the orbits of Mars and Jupiter numerous small bodies move, the largest of which are only stone blocks in comparison with the planets, less than 200 years ago. Their discovery was a natural step towards the knowledge of the world around us. This path was not easy and straightforward.
Who, in the era of the discovery of the first asteroids, could have suggested that these small bodies of the solar system, bodies that were often talked about quite recently with a touch of neglect, would be the object of attention of specialists in various fields: natural sciences, cosmogony, astrophysics, celestial Continue reading
The main types of geological structures on the moon are continents and seas. The dark sea surface occupies more of the visible side of the moon, and is practically absent on the reverse side.
MATERIALS form the upper part of the lunar crust, the composition of which is from anorthosites on the surface to dunites and troctolites at the base of the crust. The thickness of this crust is estimated from a network of seismometers left by the Apollo on the Moon and recording the passage of waves from endogenous and shock moonquakes.
In the center of the visible side, the crust thickness averages 60 km, in the areas of the Nectar and Vostochny seas it increases to 80 – 100 km, and on the reverse side it can reach 100 – 150 km. Continue reading
How did lunar craters form? This issue has led to a long discussion between supporters of two hypotheses on the origin of lunar craters: volcanic and meteorite.
According to the volcanic hypothesis, which was put forward by the German astronomer Johann Schröter in the 80s of the 18th century, craters arose as a result of grandiose eruptions on the lunar surface. In 1824, his compatriot Franz von Gruutuisen proposed a meteorite theory that explained the formation of craters by the fall of meteorites.
Only 113 years later, in 1937, a Russian student Kirill Stanyukovich (future doctor of science and professor) proved that when meteorites strike at cosmic velocities, an explosion occurs, as a result of which not only a meteorite is melted, but also some of the rocks at the site of the impact. The explosive theory of Stanyukovich was developed in 1947-1960. by himself, and then by other researchers. Continue reading