Question

What is accretion, and how does it relate to the formation of the Earth?

Answer 1

Hint:Accretion is described as the process of gas and dust being collected together by gravitational forces. Most of the astronomical objects like the galaxies, the stars and the planets are formed by the process of accretion.

Complete answer:
Accretion can happen on many different scales. For example, in the early history of our solar system, gravity caused small particles of gas and dust to collect and combine into larger and larger objects eventually growing from tiny grains of dust into planetesimals and finally into the planet that we live and we know today.

Accretion is also responsible for gathering clouds of hydrogen into stars and stars into galactic disks. Accretion is the process by which black holes are fed when a star or a cloud of material is near a black hole, it experiences the gravitational effects. The force of attraction accelerates material towards the black hole and since particles in the clouds are free to move around, they experience a force called viscosity, which is the effect of friction during collisions.During the earth’s accretion, the planet was thought to have been shock heated by the impacts of meteorite-sized bodies and larger planetesimals.

Note:It can be seen that the many processes contributing to the early development of the Earth occurred almost simultaneously within ten to hundred years after the Sun was formed. During this time, the earth and the meteorites were formed and the moon which has been dated at more than four billion years of age was also formed in the same time period.