1. From Here to The Dawn of Time A. Herrold

2. To the edge of the solar system The orbit of Neptune is not at the edge of the solar system Past the planets is the Kuiper Belt, another large asteroid belt Next is the Oort Cloud The solar system ends at the heliopause

3. The Kuiper Belt Asteroids from Neptune to beyond Pluto Pluto is a KBO ! Tens of thousands discovered Home to short- period comets

4. The Oort Cloud The home of a trillion long-period comets From 70 light-days to 3 light-years away Material in the Cloud = 40 X the mass of Earth

5. The Heliopause: Where Sun meets Stars The solar wind blows past the Oort Cloud. Other stars exert winds, too. The heliopause is where the edge of the Sun’s influence is felt.

6. The Nearest Stars to Us

7. The Milky Way The Milky Way

8. The Galaxy in Infra-red

9. The Galaxy as we know it

10. The Orion Arm

11. The Galactic Center The Galactic Center Dust and gas hide the view of the center of our galaxy in optical wavelengths.

12. The Galactic Center, Part 1 Two views of infrared: Right: a close-up Below: a wide-angle view

13. The Galactic Center, Part 2 Left: X rays Below: Radio waves

14. Black Hole at the Galactic Center – Swirling Stars

15. Nearby Galaxies

16. Spiral Galaxies Spirals have arms, a disk, a nuclear bulge and a halo. Young stars live in the disk and arms- old stars in the bulge and halo.

17. Barred Spiral Galaxies Like spirals, except they have a star bar that runs through the nucleus Why?

18. Sideways Spirals From the side, dust lanes are often visible Old, metal-poor halo stars and globular clusters surround the galaxy Dwarf spirals also exist

19. Elliptical Galaxies Contain old stars and little dust They are often found near the center of galaxy clusters Perhaps they form as a result of mergers Dwarf ellipticals often orbit larger galaxies Astronomers often call this type “red and dead”

20. Irregular Galaxies These galaxies don’t fit into the other shapes and categories Their odd shapes may be due to interactions with other galaxies They are often small and may be the most common type

21. Galaxy Interactions Galaxies within a cluster often move towards or past one another This may result in mergers, cannibalism or perturbations Smaller “dwarf” galaxies often orbit larger ones

22. Galaxy Mergers NGC 3521 shows tidal streams of materials from one or more galaxies that merged with it

23. Andromeda Galaxy – Spitzer Space Telescope

24. The Cannibalism of Centaurus A The small blue arc is a stream of stars 2000 light-years long. It is thought to be the remnants of a small galaxy that Centaurus A has “eaten”. A3827 (below) shows the remains of 5 galaxies in its belly.

25. Et Tu, Brute? Our own Galaxy is a cannibal. In the image below, clouds of hydrogen and other elements are seen falling into or lurking around the Milky Way.

26. Galaxy Clusters- Abell 1185 and the Guitar

27. The Hubble “Tuning Fork” Hubble thought galaxy shapes may evolve as a function of their age.

28. Galaxy Types and Star Formation Instead, they may exhibit 2 different star formation behaviors, or be shaped based on their history of interactions.

29. The Local Group Our galaxy belongs to a cluster of more than 45 large and small galaxies.

30. The Great Attractor Millions of galaxies stream toward a “mass” 250 miliion light years away simply known as “The Great Attractor”.

31. Superclusters The Shapley Supercluster is currently the largest known, having a diameter of more than 400 million light years.

32. The Great Wall of Sloan Superclusters seem to organize into “walls”, forming curved structures (bubbles) that seem to wrap around empty areas (voids) in the universe.

33. Nearby Neighborhoods

34. Edwin Hubble and his Law The farthest galaxies move the fastest The slope of this line is the Hubble Constant

35. The Hubble Ultra Deep Field

36. Quasars: Quasi-Stellar Objects

37. Supernovas as “Standard Candles”

38. By measuring the maximum magnitude of Type Ia supernovae, a distance can be determined. (All Type Ia SN have a peak magnitude of -19.6)

39. Penzias and Wilson vs. the Pigeons

40. WMAP: the Wilkinson Microwave Anisotropy Probe The map produced by WMAP shows the universe as it existed only 380,000 years after the Big Bang. The colors represent tiny temperature fluctuations.

41. The Early Universe according to WMAP