Orbit
Contents
Key Stage 2
Meaning
An Orbit is the path planet takes around a star and the path a moon takes around a planet.
A Planet orbiting a Star. |
About Orbits
- An orbit is a roughly circular path, but can be stretched out into an oval shape.
- The Moon orbits the Earth. This means The Moon takes a circular path around the Earth.
- All the planets orbit The Sun. This means the planets take a circular path around The Sun.
Key Stage 3
Meaning
An Orbit is the path an asteroid, comet, planet or dwarf planet takes around a star and the path a moon takes around a planet.
About Orbits
- Moons orbit planets and planets orbit the stars due to gravity.
- Newton was the first person to realise that objects were held in orbit by gravity which he explained in his Law of Universal Gravitation.
- Gravity is a constant force directed to the centre of a massive object.
- The Moon feels a force pulling it towards the centre of the Earth. The Earth feels a force equal in magnitude but opposite in direction to that of The Moon.
The planets are pulled towards The Sun by gravity. |
Key Stage 4
Meaning
An orbit is the circular or elliptical path that an object takes a more massive object due to a force of attraction acting between them.
About Orbits
- Orbits are caused by a force of attraction between two objects acting towards their centres.
- Planets orbit Stars due to the force of gravity.
Higher
- There are two types of orbit you should know:
This animation shows acceleration due to the changing direction of a circular orbit of the blue object around the red object. A circular orbit is one of constant radius. |
This animation shows the elliptical orbit of a planet around a Star. As the planet gets further from the Star the speed of the planet decreases. As the planet gets closer to the Star the speed of the planet increases. |
References
AQA
- Orbit, pages 276, 278-9, GCSE Physics; Student Book, Collins, AQA
- Orbits, page 101, GCSE Physics; The Revision Guide, CGP, AQA
- Orbits, pages 236-237, GCSE Physics; Third Edition, Oxford University Press, AQA
- Orbits, pages 249-50, GCSE Physics, Hodder, AQA
- Orbits, pages 320, 321, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
- Orbits; circular, pages 253-5, GCSE Physics, Hodder, AQA
- Orbits; speed of, pages 254-5, GCSE Physics, Hodder, AQA
Edexcel
- Orbits, page 59, GCSE Physics; The Revision Guide, CGP, Edexcel
- Orbits, pages 118, 120-121, GCSE Physics, Pearson Edexcel
- Orbits, pages 184-186, GCSE Physics, CGP, Edexcel