Astronomy GCSE : Week 3
2016–17 course delivered by Think Physics and the Centre for Life
This week we’re looking at Planetary systems, and some of the terms involved in describing the motion of planets.
Web links for Week 3
There are lots of terms that you need to remember, and be able to use. These weblinks provide more information about the meaning of the terms.
- Description of the Motion of planets
- Elongations and configurations (in a bit more detail than is needed for GCSE)
- Video explaining retrograde motion
- Minor Planet Centre
- Simulation of gravity and orbits
- Clip from Cosmos explaining Keplers Laws
Specification statements for week 3
Topic 2.1
- describe the location and nature of the main constituents of our Solar System, including planets, dwarf planets, asteroids, comets, centaurs and Trans-Neptunian Objects (TNOs)
- recall the names of planets and dwarf planets in order of their mean distance from the Sun
- demonstrate an understanding of the scale and size of our Solar System using scale models
- recall that the ecliptic is the plane of the Earth’s orbit around the Sun
- demonstrate an understanding that one astronomical unit (AU) is the mean distance between the Earth and Sun.
- recall that planets move in elliptical orbits, slightly inclined to the ecliptic
- demonstrate an understanding that the planets appear to move within a band called the Zodiac
- demonstrate an understanding of the direct and retrograde motion of planets on a star chart
- demonstrate an understanding of the terms: perihelion, aphelion, greatest elongation, conjunction, opposition, transit and occultation
Topic 2.3
- illustrate Kepler’s second law of planetary motion with the aid of a diagram
- demonstrate an understanding of Kepler’s third law relating planetary distances to orbital periods and perform simple calculations using the formula:
\(T^2 = R^3\)
where \(T\) is in years and \(R\) is in AU. - demonstrate an understanding that gravity is the force responsible for maintaining orbits and its inverse square law nature.
