1000 Things You Should Know About Space

Newton

*Isaac Newton(1642-1727) discovered the force of gravity and the three basic laws of motion.

*Newton's ideas were inspired by seeing an apple fall from a tree in the garden of his home in Lincolnshire.

*Newton also dicovered that sunlight can be split into a spectrum made of all the colours of the rainbow.

*Newton's discovery of gravity showed why things fall to the ground and planets orbit the Sun.

*Newton realized that a planet's orbit depends on its mass and its distance from the Sun.

*The further apart and the lighter two objects are, the weaker is the pull of gravity between them.

*To calculate the pull of gravity between two objects, multiply their masses together, then divide the total by the square of the distance between them.

*This calculation allows astronomers to predict precisely the movement of every planet, star and galaxy in the Universe.

*Using Newton's formula for gravity, astronomers have detected previously unknown stars and planets, including Neptune and dwarf planet Pluto, from the effect of their gravity on other space objects.

*Newton's three laws of motion showes that every single movement in the Universe can be calculated mechanically.

*Newton's theory of gravity showed for the first time why the Moon stays in its orbit around the Earth, and how the gravitational pull between the Earth and the Moon could be worked out mechanically.