1. Light & Optics: Making a Telescope Dr Lisa Jardine-Wright

2. How do astronomers make discoveries?

3. Telescopes with lenses Converging Lens Convergent rays f

4. Experiment 1 1.Move the lens until you see a bright dot next to the pin hole that is in focus. 2.Write down the distance of the lens from the pin-hole = the focal length MirrorLens (15)Pin-holeLamp About 15cm Metre Rule

5. Experiment 1 MirrorLens (15)Pin-holeLamp

6. Investigating Lenses Draw ray diagrams to investigate what happens as you move an object to the lens that its focus. And further away than the focus. lens F object F image

7. Experiment 2a Graph Paper Screen (shows image) Lens (15)Lamp Cork (object) More than the focal length of your lens Move the screen until you see a focussed image of the cork

8. Investigating Lenses Draw ray diagrams to investigate what happens as you move an object to the lens that its focus. And further away than the focus. lens F object F image

9. Experiment 2b Graph Paper Screen (shows image) Lens (15) Lamp Cork (object) Less than the focal length of your lens Move the screen can you find a focussed image of the cork

10. Experiment 2b Lens (15) Cork (object) Less than the focal length of your lens Take screen away and move the lamp to the side. Lamp Graph Paper Screen (shows image)

11. Telescope Experiment Graph Paper Screen (shows image) Lens (15) Lamp Cork (object) Lens (30) 10cm

12. Refracting Telescopes Lens 1 Lens 2 Object Image 1 Image 2 F1F1 F1F1 F2F2 F2F2

13. Refracting Telescopes Lens 1 Lens 2 Object Image 1 Image 2 F1F1 F1F1 F2F2

14. Reflecting Telescopes

16. How do we make a picture?

18. How do we make an picture? Red Green Blue

19. “Light” Visible light is just one tiny part of a much bigger range of waves called: Electromagnetic Spectrum

21. Visible Spectrum

22. Infra-red Visible

23. Light is blocked… in some wavelengths but not others. How do we “see” things?

24. Light is blocked… in some wavelengths but not others. How do we “see” things?

25. http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/

27. The Sun: Visible

28. The Sun: Radio

29. The Sun: Microwave

30. The Sun: Infrared

31. The Sun: Visible

32. The Sun: Ultraviolet

33. The Sun: X-ray

34. The Sun: Gamma Rays

35. The Light from an object can tell us …. What it looks like - Its SHAPE & COLOUR How far away it is – its DISTANCE And EVEN! What it is made of – its CHEMISTRY