1. Modern Telescopes and Ancient Skies New Views of the Universe An IU Lifelong Learning Class Tuesdays, May 10, 17, 24

3. Size and Scale Surveying the Universe from the Earth to the farthest reaches of the visible Universe

4. Galileo Galilei's "The Phases of the Moon" Image courtesy of Biblioteca Nazionale Florence, Italy Our closest neighbor

5. Visualizing the Earth from Space What do you see? –Earth –Moon –Sun –Stars Copyright 1980 by DC Comics Inc.

6. Welcome to Outer Space!

7. Earth Radius: 6400 km Distance from Sun: 150,000,000 km 1 AU, 8 light minutes Moon Radius: ¼ Earth’s radius Distance from Earth: 384,000 km

8. Solar System Sizes of planets NOT to scale Distance to Pluto: about 40 AU (about 320 light minutes)

9. The Nearest Stars The closest star to our Sun is Proxima Centauri, about 4 light years distant.

10. Most of the stars we see in the sky are within 250 light years

11. Our Sector of the Galaxy The Sun lies along one of our Galaxy’s spiral arms, known as the Orion Arm

12. View of the Milky Way Galaxy Our Milky Way galaxy contains two hundred billion stars. The Sun is about 26,000 light years from the center.

13. Our Milky Way Galaxy is part of a small cluster of galaxies.

14. Virgo Supercluster Our Local Group of galaxies is part of a larger supercluster of galaxy groups.

15. Galaxies and clusters of galaxies collect into vast streams, sheets and walls of galaxies.

16. The Visible Universe On the largest scales, the universe seems to be more or less uniform

17. With thanks to Bill Watterson, 1990

18. What will we cover????? How telescopes work Modern telescopes Sky viewing Space telescopes Kirkwood Obs Visiting the Gemini Observatory Future telescopes

19. Beginnings… This sketch of a telescope was included in a letter written by Giovanpattista della Porta in August 1609

20. Thomas Harriet’s Drawings of the Moon and Sun

21. Telescopes and how they work from lenses… to mirrors

22. Technology moves forward…

23. The 3.5-meter WIYN telescope Kitt Peak, Arizona

24. New Telescope Technology  “Fast” mirror  Lightweight mirror  Mirror shape controlled  Mechanically simpler mount  Temperature control

25. Casting the WIYN Mirror

26. Polishing the WIYN Mirror

27. The WIYN New Technology “Dome”  Compact telescope chamber  Open for ventilation  Insulated to keep cool  Heated spaces kept separate

28. Breaking the “cost curve” New technology provides better performance at lower cost WIYN

29. in 6-8 meter telescopes WIYN TECHNOLOGY

30.  text The importance of image quality typical ground- based image Hubble image WIYN image The Ring Nebula

31. Connecting the First Nanoseconds to the Origin of Life

32. How is the Universe put together?  The Wilkinson Microwave Anisotropy Probe tells us about the state of the Universe 400,000 years after the Big Bang. How did the Universe evolve from this…

33. …to this?

34. The cosmic web of intergalactic gas and galaxies in a young universe Intergalactic gas Clumps concentrated by dark matter lead to galaxies Observing the assembly of galaxies Galaxy building blocks observed with Hubble Simulation

35. WMAP also provides evidence of the first stars  Tiny fluctuations in polarization  About 200 million years after the Big Bang

36. We can almost see the first stars Simulation What we might see with a 30-meter telescope (Barton et al., 2004) 4 million LY hydrogen emission from hot stars Green=hot gasyellow=stars

37. The composition of stars and gas: everything else 90% hydrogen atoms 10% helium atoms Less than 1% everything else What is the Universe made of?

38. But ordinary matter is only part of the story… 96% of the Universe is something else

39. Galaxy interactions require more mass than we can see Antennae Galaxy (HST) Computer simulation The real thing

40. Dark Matter  The universe contains additional matter we cannot see  Dark matter interacts with normal matter through gravity  Dark matter does NOT interact with light the way the normal matter does  The Universe contains 5 or 6 times MORE dark matter than normal matter  All galaxies are embedded in clouds of dark matter  We do not know what it is!

41. “Redshift” of Galaxies  The spectra of galaxies are shifted to the red: galaxies are moving away from us.  The farther away a galaxy is, the faster it recedes from us!

42. Hubble’s Law

43. The speeds of very distant galaxies tell us the Universe is expanding faster today than in the past The brightness of stellar explosions tells us how far away galaxies are

44. The universe is expanding faster today than it did in early times This expansion cannot be caused by ordinary or dark matter, which slows expansion. The acceleration suggests a new repulsive force (anti-gravity) acting on very large scales The Universe is speeding up!

45.  Dark energy accounts for 73% of the content of the universe  Dark matter accounts for 23%  The content we’re familiar with is only 4% The New Force Is Called “Dark Energy”

46.  We don’t know What is Dark Energy? Identifying what dark energy is requires bigger telescopes and new techniques

47. Connecting the First Nanoseconds to the Origin of Life

48. Kirkwood Observatory Viewing  Tuesday evenings, weather permitting

49. Night Sky Viewing Scheduled nights –Tuesday, May 17 –Tuesday, May 24 Roof of Swain West

50. Next Week Telescopes in Space, including the Hubble Space Telescope New Views of the Universe – Planets around other Suns Kirkwood Obs and Rooftop, weather permitting

51. Is there life elsewhere? Artist’s conception of 55 Cancri’s planetary system More than 150 planets found around other stars Most are vastly different from our Solar System

52.  detecting planets directly is hard  planets are small and dim  planets are near much brighter stars  detecting planets directly requires large telescopes (30-meters) and/or special instruments Detecting Planets

53. Imaging planets around other stars “Brown Dwarf” orbiting a star at the same distance as Saturn from our Sun Gemini/Keck AO detection by Michael Liu (IfA), 2002

54. With a 30-meter telescope we can obtain the spectra of planets around other stars to search for the signatures of life Simulation by Sudarsky et al. 2003 Simulation of the spectra of 55 Cancri’s planets