1. Observing the Universe From the Lens to Multi-wavelength Astronomy

2. Outline History Modern Observatories The Electromagnetic Spectrum Multi-wavelength Astronomy Radio Astronomy Sub-mm, IR Astronomy X-ray Astronomy Gamma-ray Astronomy

3. In the beginning... ~500 bc

4. Planetary Motion http://www.syz.co m/DU/mac/animat ions/planetarymoti on.html

5. Post-Renaissance Developments

6. Dutch Lens Maker Invented the Telescope in 1608 Hans Lippershey (1570-1619)

7. Galileo Galilei (1564-1642) Italian Mathematician who laid the foundations of modern science and established the Copernican Model of Solar System

9. Sir Isaac Newton (1642-1727) British Mathematician who (amongst many great achievements) invented the reflecting telescope and discovered the spectral nature of light

10. The Spectral Nature of Light

11. The Development of Astrophysics and Modern Astronomy (or build a bigger telescope)

12. Sir William Herschel (1738-1822) 18” Reflector Catalogued the sky by eye

13. Earl of Rosse (1800-1867) and the his 72” Leviathan

14. Sir William Huggins (1842-1910) The first astrophysicist Observed the spectra of Herschel's nebulae

15. Photographic Developments

16. Modern Astronomy In the 20 th Century all new observatories were built on mountain tops to evade light pollution and improve the seeing.

17. z z0z0 n n+dn n0n0 z+dz Atmospheric Refraction and Adaptive Optics

18. Hubble Space Telescope 2m reflector

19. The Electromagnetic Spectrum

20. Blackbody Radiation As the temperature of an object increases its brightness will increase as T 4 and its peak wavelength will decrease as T -1. Therefore, hot things emit shorter wavelength radiation, e.g. X-rays. Whereas cooler things emit longer wavelength radiation e.g. IR.

21. Karl Guthe Jansky (1905-1950) Grote Reber (1911-2002) Radio Astronomy q ∝ l / D

22. Radio Interferometry

23. Radio Astronomy Observations Radio galaxies, and Quasars

25. Radar Astronomy or Active Radio Astronomy transmit radio waves to nearby planets and asteroids to determine distances and shapes just like aircraft radar

28. X-ray Astronomy XMM Satellite

29. X-ray Astronomy – Observations

30. Gamma-ray Astronomy – INTEGRAL Satellite

31. x I Coded Mask Point-sources Detector 1 2 Shadowgram of ps 1 Shadowgram of ps 2 Gamma-ray Astronomy – Coded Mask Imaging Cannot focus gamma-rays by reflection, so use coded masks. A pattern of opaque and transparent elements produces a shadowgram. Decode image by moving pattern over shadowgram with image processing software.

32. Required to observed the highest energy gamma-rays Gamma-ray Astronomy – Cerenkov Detectors