Edexcel GCSE Astronomy Topic 11 Exploring the Solar System: a complete overview of the bodies, comets, space probes and exploration

What Topic 11 actually demands

Exploring the Solar System covers the contents of the Solar System and how we explore them. It rewards description (comet structure, the bodies) and evaluation (the probe types, probes versus manned missions). The telescope-design statements of Topic 11 are covered in the telescopes guide.

This guide walks through the dot points, then sets out the exam patterns Pearson repeats. Each dot point has a matching page with practice questions; this overview ties them together.

The bodies and comets

The Solar System has the Sun, eight planets, dwarf planets and small Solar System objects (asteroids, meteoroids, comets), mostly near the ecliptic. A comet has a nucleus, coma and tails (always pointing away from the Sun). Short-period comets come from the Kuiper Belt (a disc beyond Neptune); long-period comets from the spherical Oort Cloud. The planets differ in size, mass, temperature, atmosphere, moons and rings.

Space probes and exploration

The four probe types are fly-by (New Horizons), orbiter (Juno, Dawn), impactor (Deep Impact) and lander (Philae). Probes need escape velocity (only rockets supply it). Robotic probes are cheaper and safer; manned missions (the Apollo programme) add human judgement. Transits of Venus were used to measure the AU.

How Topic 11 is examined

A typical Edexcel profile for exploring the Solar System:

• Description. Comet structure and origins, and the bodies of the Solar System.
• Evaluation. The probe types and probes versus manned missions.
• Recall. Escape velocity, the Apollo programme, and transits of Venus.
• Data. Reading the planetary characteristics from the data sheet.

Check your knowledge

A mix of description and evaluation questions covering Topic 11. Attempt them under timed conditions, then check against the solutions.

1. State the three main parts of a comet. (1 mark)
2. State which way a comet's tail points and why. (2 marks)
3. State where short-period comets are thought to originate. (1 mark)
4. State where long-period comets are thought to originate. (1 mark)
5. Describe the difference between a fly-by and a lander probe. (2 marks)
6. Give one advantage of robotic probes over manned missions. (1 mark)
7. State what transits of Venus were used to measure. (1 mark)