Scientists agree that the Earth formed about 4.6 billion years ago out of accreted matter from the solar nebula. All planets in the solar system formed the same way. Once the proto-Earth was formed, many changes occurred over vast timescales to produce the Earth of the 21st century.Know More
The formation of Earth's atmosphere is attributed to early volcanic activity. The early Earth remained molten due to continued volcanic activity as well as frequent collisions with other celestial bodies. One of the biggest of these collisions is thought to have tilted the Earth on its axis while simultaneously creating the moon. Once the Earth cooled and formed a solid crust, liquid water was able to cover parts of this surface.
The earliest life appeared between 3.8 and 3.5 billion years ago, by way of a process that remains unknown. Life on Earth remained microscopic until approximately 580 million years ago, when the first multicellular life forms developed. Earth's life forms and geology are constantly changing, as new species evolve and others go extinct, and plate tectonics keep the structure of the Earth in a constant state of flux.Learn more about Earth Science
The shape of the Earth is classified as an ellipsoid or an oblate spheroid. The Earth is not considered a true sphere because it has a larger circumference and diameter at the equator. The poles of the Earth are squished, which creates a slight bulge around the equator.Full Answer >
The volume of the Earth is 1.44 x 10^21 cubic yards or 2.63 x 10^10 cubic miles. This is found by taking the diameter of the Earth, which is roughly 7,962 miles at the equator, and applying the formula, V = 4/3 pi r^3.Full Answer >
In the year 1515, Nicolaus Copernicus theorized that the Earth was a planet and discovered the idea of a heliocentric solar system, a system in which all planets revolved around the sun. He built his own observatory in 1513 to help him watch the actions of planets.Full Answer >
If the Earth had no axial tilt, there would be no seasons. The climate would remain the same for a given location on Earth year-round, and life as commonly known would likely not exist.Full Answer >