Earth is our home planet, the planet on which we live, the third of eight planet in our host star system we commonly refer as Solar System. It is the only planet in the known universe, known to harbor and support life, multiple interdependent subsystems and various vegetation systems. Earth is the fifth largest planet in the solar system, densest of all the planet, largest of all the planets relative to size of its natural satellite.

Earth rotates on this axis every 23.9 hours, which defines day and night for us. The axis of Earth is tilted 23.4 degrees that gives us seasons (winter, spring, summer and autumn).

Earth have different subsystems also called spheres of Earth. Atmosphere, Hydrosphere, Lithosphere, Biosphere, Cryosphere are the main spheres of the Earth.

Earth Day: April 22

Earth Hour: Non-essential electric lights are turned off between 8:30 PM to 9:30 PM on a specific day at the end of month March