TO INFINITY AND BEYOND

How can new ideas cause controversy and conflict?

Astronomy is the science which studies the planets, the stars and other celestial bodies in the Universe.

Astrology is based on the ancient belief that the stars and planets control our lives. The signs of the Zodiac represent the twelve constellations of stars through which the Sun appears to pass every year.

Astronomy and Astrology are NOT the same!

Theories about the universe

Are we the centre of the universe? In the past, theories about the universe

came from observations made with the eye looking at the sky at night, then TELESCOPES came along!

The main theories about the universe before this time (and even after!!) were “Geocentric Theory” and “Heliocentric Theory”

Geocentric Theory

Most ancient Greeks beleived that the Earth lay at the centre of the universe. Claudius Ptolomy (AD 100- 165), a great astronomer, argued that the stars and planets moved around the Earth in circles , because the circle was a perfect shape created by the gods.

Geocentric Theory

Heliocentric Theory This description of how the universe

worked was accepted for more than 1,500 years, until Nicolas Copernicus (1473- 1543) realized that the movements of the Earth were explained more easily if the Sun, not the Earth, lay at the centre. But he did not dare to publish his theories until the year of his death.

Heliocentric Theory

What we know now Nowadays, we know that none of these

theories are correct. The Sun is only a little Star in one of the billions of galaxies in the universe.

Small ideas, big results http://ed.ted.com/lessons/how-simple-

ideas-lead-to-scientific-discoveries

Age of Discoveries Johannes Kepler (1571-1630) discovered

that the orbits were ellipses and enunciated three laws, deducing from the observations made by his master Tycho Brahe (1546-1601), which explained the motion of the planets. Galileo (1564-1642) built a telescope (the telescope of Galileo) in 1609 and, based on his observations and theories formulated by Kepler, with whom he corresponded, discovered several celestial bodies.

Isaac Newton (1642-1727) completed the Kepler laws, showing that they were just special cases of more general laws. Newton's laws of motion enunciated what is considered the basis of all the mechanics of the universe, the Law of Universal Gravitation, which introduces the concept of gravitational force.

Earth gravity : 9,8 m/s2

What is Gravity? http://

ed.ted.com/lessons/jon-bergmann-how-to-think-about-gravity

Why is Gravity there?