Science Unit-1

1. Origins of the universe

1.1. The universe is space and all that exists including planets,stars and other celestial bodies and galaxies.

1.2. There are lots of theories and one of the most famous is the Big Bang theorie.

1.3. The Big Bang is the explosion that creates the universe.

2. Galaxies

2.1. Types of galaxies:

2.1.1. Elliptical galaxy, barred spiral galaxy

2.1.2. Spiral galaxy irregular galaxy

2.2. The Milky Way

2.2.1. Our galaxy is part of cluster known as the Local Group.

3. Geocentric model

3.1. Aristotle

3.2. Claudius Ptolemy

4. Celestial Bodies

4.1. Satellites

4.2. Asteroids

4.3. Comets

4.3.1. Meteoroids

5. Planets

5.1. Rocky Planets

5.1.1. Mercury,Venus

5.1.2. Earth,Mars

5.2. Gas planets

5.2.1. Jupiter,Saturn

5.2.2. Uranus,Neptune

6. Heliocentric model

6.1. Aristarchus of Samos

6.2. Nicolaus Copernicus

6.3. Galileo Galilei

6.3.1. Johannes Kepler