Around 4.5 billion years ago, neither the Earth nor any of the other planets existed. There was 
just a vast, dark, very hot cloud of gas and dust swirling around the newly formed Sun. Gradually, the cloud cooled and the gas began to condense into billions of droplets. Slowly these droplets were pulled together into clumps by their own gravity~and they carried on clumping until all the planets, including the earth, were formed. But it took another half a billion years before the Earth had cooled enough to form a solid crust with an atmosphere around it.
just a vast, dark, very hot cloud of gas and dust swirling around the newly formed Sun. Gradually, the cloud cooled and the gas began to condense into billions of droplets. Slowly these droplets were pulled together into clumps by their own gravity~and they carried on clumping until all the planets, including the earth, were formed. But it took another half a billion years before the Earth had cooled enough to form a solid crust with an atmosphere around it.How big is the Earth?
Satellite measurements show it is 24,870 miles (40,024 km) around the equator and 7,927 miles (12,578 km) across. The diameter at the Poles slightly less, by 26.7 miles (43 km).
How old is the Earth?
The Earth is about 4.6 billion years old. The oldest rosk is about 3.8 billion years old. Scientists have alos dated meteorites that have fallen from space, and must have formed at the same time as the Earth.
What is the Earth made of ?
The Earth has a core of iron and nickel, and a rocky crust made of mostly oxygen and silicon. in between is the soft, hot mantle of metal silicates, sulphides, and oxides.
What is the shape of the Earth?
The Earth is not quite a perfect sphere. Becasue it spins faster at the equator that at the Poles, the Earth bulges at the equator. Scientists describe Earth's shape as "geoid," which simply means Earth-shaped.
The Earth is not quite a perfect sphere. Becasue it spins faster at the equator that at the Poles, the Earth bulges at the equator. Scientists describe Earth's shape as "geoid," which simply means Earth-shaped.
What's so speacial about the Earth?
The Earth is the only planet with tempratures at which water can exist on the surface and is the only planet with an atmosphere containing oxygen. Water and oxygen are both needed for life.
Why does the Earth spin
The Earth spins because it is falling around the Sun. As the Earth hurtles around the Sun, the Sun's gravity keeps it spinning, just as the Earth's gravity keeps a ball rolling downhill.
Exactly how long is a year? 
Every year the Earth travels once around the Sun. This epic journey covers a distance of 548,018,150 miles (938,886,400 km) and takes exaclty 365.724 days, which gives us our calender year of 365 days. To make up the extra 0.24 days, we add an extra day to our calender at the end of February in every fourth year, which is called the leap year~and then we have to knock of a leap year every four centuries.
How long is a day?
A day is the time the Earth takes to turn once. The stars are in to the same place in the sky every 23 hours, 56 minutes and 4.09 seconds (the sidereal day). Our day (the solar day) is 24 hours, because Earth is moving around the Sun, and must turn an extra 1 degree for the Sun to be in the same place in the sky.
Who was Copernicus?
In the 1500's, most people thought the Earth was fixed in the center of the universe, with the Sun and the stars revolving around it. Nicolaus Copernicus (1473-1543) was the polish astronomer who first suggested the Earth was moving around the Sun.
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