Question

when did earth was born

Answer 1

According to scientists, Earth was born around 4.54 billion years ago.............

Answer 2

Impossible to say. Ignoring that fact that the date and time systems we are familiar with are entirely human constructs, we simply can't measure it with that degree of precision, and besides, what point do you choose as the "birth" of the Earth? When the nebular cloud of our solar system began to collapse? When the first planetesimals on our orbit began to accrue? When it became large enough to become spherical under its own gravitation? When it reached a similar size or mass to what it has today? When the smaller planet that collided with us and threw out the material that went on to form the moon hit? When the crust solidified (bearing in mind parts of the crust aren't solid even today)? When the atmosphere was formed? These all took place at different stages in the Earth's formation, a process that was continuous and took a long time. The closest we can get to an answer is 4.55 billion years, give or take 1%, which is the age of the solar system based on radiometric dating of meteorite material that also formed during the accretion phase of the planets.