Why is earth so special?

 Earth is a special spot in solar system for so many reasons - 

its sprawling continents,its blue sea,its nearly limitless varieties of ice cream flavours. But one earthly thing stands out about the rest : its earthlings. Ours is the only plant currently known to harbour life. Earth's unique combination of air,water and land nurtures life of every sort from microscopic amoebiasis to submarine-size blue whales.

 What makes the world go around?

Earths rotation is the side effect of formation of solar system, which started as a massive cloud of gas and dust roughly 4.6 billion years ago. The cloud began to rotate as it scrunched together under his own gravity. The material at the center eventually become the sun, while whirlpools of dust and gas farther out spun faster and faster until they become planets. With nothing to stop its spinning motion. Earth retained the motion from its early days.

How fast does the earth spin ?

Along the equator- the imaginary line halfway between the north and south poles. Earth rotates at 1037 mph.

Why is the earth round?

Actually, its not a perfectly round. It's an "oblate spheroid",a sphere that is slightly wider at the equator than at the poles. Gravity squashed earth and the other solar planet into the spherical shapes back when they formed from clouds,dust and gas. Earth's rotation causes its slight bulge around the middle.

What will happen if earth takes longer than 24hours to rotate ?

It will make day and night longer. Our weight would be more because earth would rotate slower. It would exert a less centrifugal force on us. The resultant force of earths gravity and centrifugal force would  be more as gravity and remain constant but centrifugal force will decrease. There would also be temperature change as each hemisphere would get more time to warm up from the sun rays.

Who first said that earth revolves around the sun ?

In 1543, Nicolaus Copernicus detailed his radical theory of the Universe in which the Earth, along with the other planets, rotated around the Sun. His theory took more than a century to become widely accepted.