Asteroids are so small that the force of gravity on them void. She was not able to give them a shape of a ball, what makes planets and their large satellites, crushing and stamping their substance. A great role is played by the phenomenon of fluidity. High mountains on the Earth at the foot of the "creeping", because the strength of the rocks is insufficient to withstand many tons per 1 cm3,and stone, not fractions, not raskalyvanii, flows, albeit very slowly.

Asteroids with the diameter of up to 300-400 km because of small weight are there rocks similar phenomenon fluidity absent, and the largest asteroids it is happening very slowly, and then only in the subsoil. So "rammed" gravity can only be deep bowels of the few large asteroids. If the substance of the asteroids are not passed the stage of melting, it was to remain a "bad Packed", about what occurred at the stage of accumulation in protoplanetary cloud. Only the collision of bodies with each other could lead to substance gradually Minlos, becoming less loose. However, new clashes had to split the compressed substance.

A small force of gravity allows broken asteroids exist in the form of units consisting of separate blocks, kept near each other by the forces of gravity, but not merging with each other. For the same reason, do not merge with them and descended to the surface of asteroids their satellites. The moon and the Earth, coming in touch with each other, slilis would like merge (albeit for a different reason) who drops, and after some time it would be one, too spherical body, in the form which it was impossible to guess what it was. However, all the planets of the Solar system on sacchitello the stage of forming incorporated fairly large body who failed to become independent planets or satellites. Now traces of them anymore.

Only the largest asteroids can maintain its spherical form, acquired in the period of formation, if they manage to avoid collisions with small bodies of comparable size. Collisions with small bodies will not be able to change it. Small asteroids should have and really have an irregular shape, formed in the result of many confrontations and not subjected to further alignment under the action of gravity. The craters, which emerged on the surface of even the largest asteroids in the collision with small bodies, "do not enter" over time. They are saved others until will not be erased during the next shock about the small asteroid bodies, or immediately destroyed by a large body impact. Therefore mountains on asteroids can be much higher, and depression is much deeper than on the Earth and other planets : the average deviation from the level of a smooth surface in large astroid is 10 km and more, as evidenced by radar observations of asteroids.

Wrong shape of the asteroid is confirmed by the fact that their Shine extremely rapidly decreases with growth phase angle. The moon and mercury similar gloss reduction is quite explained only by the reduction visible from Earth share of the sunlit surface: the shadow of the mountains and valleys have little impact on the overall brilliance. So with the asteroids. With just one change sunlit share the surface of the asteroid rapidly changing of their brightness, which can occur is impossible to explain. The main reason (especially in asteroids small size) of this nature changes Shine is their irregular shape and extremely Israeli, which on Sunny side of one surface shield others from sunlight.