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Timewatch: StonehengeSunday, 29th March 2015 22:05 - BBC FourTwo of Britain’s leading archaeologists and world-renowned experts on Stonehenge, Professor Tim Darvill and Geoff... Read more: OU on the BBC: Timewatch - Stonehenge
Thinking Allowed: Global clothing and poverty, fur inheritance in PolandMonday, 30th March 2015 00:15 - BBC Radio 4
A History of Ideas - How do I live a good life?Monday, 30th March 2015 12:04 - BBC Radio 4
Kim Cattrall on Antony & CleopatraTuesday, 31st March 2015 04:40 - Sky Arts 1 HD
The Bottom Line - Corporate scandalAvailable until Saturday, 26th March 2016 14:15How do companies recover from negative press? Evan Davis hears from guests who have broken away from scandal on this... Read more: The Bottom Line - Corporate scandal
Turn your bank holiday into a badged holidayWhat are your plans for the long weekend? DIY? A trip to a windswept beach? Why not take your... Read more: Turn your bank holiday into a badged holiday
Take the photographic memory testCan you capture scenes just by looking at them? Find out with our photographic memory test. Launch now: Take the photographic memory test
Early years team work and leadershipThis unit explores aspects of teamwork and leadership for early years practitioners. Try: Early years team work and leadership now
Succeed with maths – Part 1[BETA] If you feel that maths is a mystery that you want to unravel then this short 8-week course... Try: Succeed with maths – Part 1 now
The sun dominates our lives by defining our day, but how much do you know and...
The sun dominates our lives by defining our day, but how much do you know and understand about it? This unit will help you to explore the workings of the brightest star in our universe looking at its structure and the main processes taking place within it. You will also examine the phenomena of sun spots.
At the end of this unit you should:
- know about the electromagnetic spectrum and how it is used to infer properties of sources of radiation;
- know about the range of sizes, distances and motions of objects in the Universe and how they can be measured;
- know about the structure of, and the main processes operating in, the Sun;
- comprehend concepts lying well outside everyday experience, including those that involve very large and very small distances, times, temperatures and energies, and those that are non-intuitive;
- develop the skill of being able to receive and respond to a variety of information sources including textual, numerical, graphical and visual material.
For astronomers, the Sun is fascinating because it is our nearest star. By studying the Sun, they can gain an insight into the workings of the other millions of stars that are visible in the night sky. Learning that the Sun is a star can be a little surprising. After all, the Sun is a brightly glowing, yellow object – so bright that it is dangerous to look at it directly, and so hot that we can feel its radiation warming the whole Earth. Stars, on the other hand, are mere silvery pinpoints of light that are visible only against the darkness of the night sky and with no discernible heating effect on Earth. How can they possibly be the same sort of object? The key to the answer lies in their distances.
In astronomical terms, the Sun is relatively close, being only about 150 million kilometres (93 million miles) from Earth. The stars that are visible at night are much further away: the nearest is about 40 million million kilometres from Earth, and most are much more distant than that. Imagine looking at a glowing light bulb first from very close up and then from a much greater distance. Close up, you would see the shape of the bulb but, from far away, it would be just a point of light.
This unit is from our archive and is an adapted extract from Introducing astronomy (S194) which is no longer taught by The Open University. If you want to study formally with us, you may wish to explore other courses we offer in.
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This is an extract from an Open University course which is no longer available to new students. If you found this interesting you could explore more free Physics and Astronomy course units or view the range of currently available OU Physics and Astronomy courses.