1. Space and Gravity
By:Nikitha

2. Definitions
Gravity- the force that attracts a body towards the center of the earth, or towards any other physical body having mass.
Mass - a large body of matter with no definite shape
Weight - a body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing.

3. What is the Difference
The mass of an object is the amount of matter or "stuff" it contains. Weight is a force caused by gravity. The weight of an object is the gravitational force between the object and the Earth. The more mass the object has the greater its weight will be.

4. We have seasons/ Changes in length of day because the Earth is tilted 23.3 degrees as it orbits the Earth.

5. Natural Satellite: A celestial body that orbits another celestial body of greater mass
The Planets
Artificial Satellite: Human-built objects orbiting the Earth and other planets in the Solar System.

6. Stars, Galaxy and Universe

7. Definitions
Visible light is a form of  radiation, as are radio waves, infrared radiation, ultraviolet radiation, X-rays and microwaves.
Electromagnetic Spectrum the range of wavelengths or frequencies over which electromagnetic radiation extends.
Infrared light is one type of light that is invisible to us. Gamma rays, X-rays, ultraviolet light, microwaves and radio waves are other types of invisible light

8. How can we learn?
Scientist can explore the Space with Space probes, these land on different planets and take pictures of them.

9. What affects Motion of planet, moons, stars and spacecraft?
The bigger you get, the stronger the gravitational pull. So size affects the strength of gravity.

10. What affects strength of Gravity?
Three Factors that affect the strength of gravity are:
Altitude
Depth Below the Earth's Surface
Rotation of the Earth