Earth originated from sun. Due to great explosion of sun, many parts of the sun gets spread in the space and began to revolve round the sun in its own axis. That is how the planets were created. The temperature of the Earth was almost similar to that of sun. Earth was in liquid state. It took 1000s of years to loose its heat & get solidified. Due to gravitational force, a part of it remained in gaseous state. We call it Atmosphere. The outer part of the Earth is called Lithosphere / Earth's Crust. The core of the Earth is very hot & liquid. The part of the Earth which is watery, is called Hydrosphere.
The world of living organisms on the earth is Biosphere. It has been found by the geological experts and other scientists that after certain years, nature destroys everything on the Earth. Again the whole process starts from the beginning. The nature gives birth to the living organisms. Plants, animals and other life grow up and began to survive in the new world. Therefore, if I say that death is the beginning of the new world, is not wrong. Scientists have put forward many theories and hypothesis like Big Bang Theory, Nebular Hypothesis, Planetesimal Hypothesis, Tidal Hypothesis, Twin Sun Theory, etc . These theories not only describes about the origination of the Earth but also about other planets, satellites and other heavenly bodies in the space, in this solar system. Mars is the only planet which got separated from the Earth, thousands of years ago.
They have done many experiments to know about the origin of the Earth. They went to the poles and experimented the ice berg to know about the past or the origin of the earth. Just to know more, scientists reached the planet Mars for further experiments. Still they are in dark. Few years ago the problem of black hole became a great matter of concern. A new machine was invented and drilled into the Earth. However, NASA began to think that the black hole might engulf the Earth and the whole of the solar system. Everything would come to an end. For the time being, experiment is in-progress by the researchers.