1. ASTR 1020 – April 4 . Next Observatory opportunity April 6 at 8:30pm
Third mid-term April 20
Tycho’s Supernova Remnant 1579

2. Dark Matter Rotation Curves Speed of Rotation Stability
Only 10% of matter in Milky Way is in stars, gas and other normal matter
Same as rest of universe
Don’t know what dark matter really is.

3. A Spiral Galaxy Like Milky Way

4. Interstellar Medium 10% of normal matter in gas – 90% stars
New stars form from this gas
Fundamental Part of the evolution of galaxy
Very Dynamic Place

5. Reflection Nebulae

7. HII Regions

9. Star Forming Regions
High Density leads to
high star formation

14. Dust Cloud Dust forms from C,O,Si,Fe etc. Like dust storm at sunset
Reddens stars beyond

19. Molecular Clouds Dust in Space Dark dust clouds
Very cold in the middle & shielded from UV
Molecules Form
H, C, N, O H2
H2O
NH3
CH4
Even Ethyl Alcohol!

20. Planetary Nebulae Red Supergiant Shedding Its Envelope
As we’ve discussed before.

25. Bubbles
Stellar Wind
Interstellar Gas

27. Supernova Remnants Four Phases Free Expansion 200 years
Energy Conserving 10,000years
Momentum Conserving 100,000 years
Confusion 1,000,000years

28. SN1987A First Naked Eye Supernova since 1604
Located in Magellanic Cloud at 55,000pc

29. SN1987A Now

30. Cassiopeia A
Exploded in late 17th Century – Not Seen

31. Kepler’s Supernova

32. Tycho’s Supernova

33. The Crab Nebula Supernova 1054
Visible Light
X-rays

34. SN 1006

35. Puppis A

36. Vela SNR (and Puppis)

37. Cygnus Loop

38. Entire Sky in Soft X-rays

39. Super Bubbles Shock Wave Hot Bubble New Stars Form Superbubble Grows
Takes Millions of Years to Grow

41. Galactic Fountain Hot Material Churns Upwards Rains back down
Galactic Halo
Galactic Fountain
Much like a bubble bath

42. Galaxies There are about 100 Billion Galaxies in Visible Universe
The Milky Way is very typical (100Billion stars)
But they come in all kinds of shapes and sizes

43. Local Group
M31 MW
Magellanic Clouds
M33

44. M31 The Great Nebula in Andromeda

45. M33 The Third Wheel of the Local Group

46. Our Region
15,000,000pc
Local Group
Virgo Cluster
M81,82

47. Brightest Seen Through Telescopes
Photography showed galaxies all over sky in 1890’s
Debate raged until 1920’s “whirlpools of gas or island universes?”
Mt Wilson Telescope resolved M31 like Galileo did Milky Way
Distance scale very difficult to determine

50. Hubble Sequence
(not an evolutionary sequence!)

53. Elliptical Galaxy

54. Elliptical

55. Sombrero Galaxy

70. M87 in Virgo Cluster