1. “Our galaxy, the Milky Way, is one of 50 or 100 billion other galaxies in the universe. And with every step, every window that modern astrophysics has opened to our mind, the person who wants to feel like they're the center of everything ends up shrinking.” - Neil deGrasse Tyson

2. 1. The Sun will ultimately become a? a.White dwarf b. brown dwarf c.Neutron Stard. Black hole 2. Low mass stars use what element to start fusion? a. Carbonb. Iron c. Hydrogend. Helium 3. Stars can only build up to what element? a. Ironb. Silicon c. Bariumd. Carbon 4. Pulsars are? a. Neutron stars facing usb. White dwarfs c. Black holesd. Neutron stars not facing us 5. The next stage of the sun is a? a. White dwarf b. Red giant c. Planetary Nebulad. Red Supergiant

3. Interstellar Gas Cloud. Nebular Cloud. Nebula. They all kind of mean the same thing. Nebular cloud begins to _______, and an ________ disk forms, with _______. When temp reaches about _______º K, star becomes a ______ __________. Star runs out of fuel. Sun becomes ___ ______, large stars become red __________ ____________. Sun forms planetary nebula and _____ ________. Large stars nova, and form ______ ________. Huge stars nova, and form ________ __________. Our sun, ______ ____ Large star, to _____ ____ Huge star to ______ _____

4. Interstellar Gas Cloud. Nebular Cloud. Nebula. They all kind of mean the same thing. Nebular cloud begins to collapse, and an accretion disk forms, with protostar. When temp reaches about 10,000,000º C, star becomes main sequence Star runs out of fuel. Sun becomes red giant, large stars become red super giants. Sun forms planetary nebula and white dwarf. Large stars nova, and form neutron star. Huge stars nova, and form black hole. Our sun, white dwarf Large star, to neutron star Huge star to black hole

5. GALAXIES AND COSMOLOGY DAY 6

6. Astronomers knew of these objects in space called nebulae but they found weird spiral shaped nebulae that confused astronomers. How did they get their shape and what were they made out of? In the 1920’s, Edwin Hubble was looking at these spiral nebulae to see what they consisted of and if they were inside our Milky Way. He could resolve stars inside the spiral nebulae and used variable stars to find distance. It was found that they were outside our galaxy and were itself a galaxy. HISTORY

7. With the discovery of other galaxies, the search was on to find more of them. Hubble discovered a few kinds and classified them. HUBBLE TUNING FORK

8. MODERN TUNING FORK

9. Spiral galaxies are classified by having a spiral like feature and central bulge. They also contain lots of gas and dust with young blue stars with high metallicity (called population 1 stars). There are two kinds of spirals, Barred and non-barred. This feature is found in the central bulge and has a bar shape. Then we continue classifying by looking at the size of central bulge and tightness of the spiral arms. SPIRAL GALAXIES

12. OUR OWN GALAXY – THE MILKY WAY Contains about 400 billion stars 100,000 light years in diameter and 10,000 light years in thickness The sun takes 240 million years for one orbit ( we are in a spiral arm )

14. LETS LOOK AT OUR MILKY WAY http://www.eso.org/public/images/eso1242a/zoomable/ http://www.chromoscope.net/

15. SO galaxies are galaxies that have a disk-like feature but have no spiral arms. They contain very few hot, bright stars and very little gas and dust. SO GALAXIES

16. EXAMPLE

17. Irregular galaxies have no predictable structure (no symmetry). They contain young and old stars. This is just a mix bag of random galaxies that can’t be categorized. IRREGULAR GALAXIES

18. EXAMPLES

19. Elliptical galaxies are galaxies with no visible gas, dust, or young stars. Star formation is not observed and consists mostly of old stars Look like spheres or football shape They are usually the largest or smallest galaxies found. They are classified further by how elliptical they look. Astronomers use the elliptical index to classify this differentiation between them. The range is from E0-E7. ELLIPTICAL GALAXIES

20. EXAMPLES

21. ARE COLLISIONS BETWEEN GALAXIES COMMON? How many suns put edge-to- edge would it take to reach the nearest star (α Cen)? How many Milky Ways put edge-to-edge would it take to reach the nearest large galaxy (Andromeda)?

22. GALAXY COLLISIONS Spirals have been involve in few collisions Ellipticals have been involved in many collisions

25. COLLISION WITH OUR SISTER GALAXY – ANDROMEDA https://www.youtube.com/watch?v=fMNlt2FnHDg

26. COSMOLOGY – THE STUDY OF THE ORIGIN AND DEVELOPMENT OF THE UNIVERSE

27. LOOKING INTO THE PAST

28. THE EXPANDING UNIVERSE In 1929, Edwin Hubble, found that the universe was expanding by looking at the Doppler Effect of galaxies. All of them appeared to be moving away from one another like pieces of material moving away from an explosion The farther away the galaxy the faster it was moving away – This was called Hubble’s Law This was using the Red Shift of the galaxies to find this speed!

29. V r = H 0 D (where H 0 is about 70 km/s-Mpc) HUBBLE’S LAW

30. REWINDING TIME BACK Using Hubble’s Law we can rewind the explosion to find the age or time of the explosion. This turns out to be around 13.7 billion years! This “point” that the universe came into exist was called the Big Bang Arguments continued if the Big Bang was a valid theory until the 1950s. In the 1950’s when two astronomers, Penzias and Wilson, found the Cosmic Microwave Background (CMB)

31. The Cosmic Microwave Background came from the Recombination stage of the universe

32. CMB It was theorized that the CMB would be around 3 Kelvin at this point and time. This is what Penzias and Wilson found. We can potentially look even deeper into the past using neutrinos!

33. WHO WANTS TO SEE A BABY PICTURE OF ME?

35. Planck Spacecraft 2013 Image

36. THE MYSTERY'S OF THE UNIVERSE & THE FATE OF IT ALL

37. WHEN LOOKING AT GALAXIES AND GALAXY CLUSTERS When looking at stars in galaxies and galaxies in clusters, it appears that everything is moving faster than it should. The stars should be moving slowly on the outsides of galaxies, but they do not! Galaxies are moving to fast to stay in clusters, but they do! There is a mysterious matter that we can not see that holds these things together! Astronomers call this Dark Matter.

38. WHEN LOOKING AT SUPERNOVAS When two research groups started to look at supernovas in the 1990s, they found that they were dimmer than predicted. This meant they were farther than they were supposed to be based on other measurements. This showed that the universe was expanding and speeding up still rather than slowing down. There is a mysterious force that is speeding up the universe. This is called Dark Energy.

39. EVERYTHING IN THE UNIVERSE How much do you think this makes up the universe? Trillions of stars 100+ billion galaxies Uncountable asteroids, comets, and meteoroids You and I Only 4.5 % of the universe!

41. THE FATE OF OUR UNIVERSE It turns out that our universe is just under the requirement for it to collapse. Dark energy outweighs matter. This means we are a flat universe that is constantly accelerating faster and faster!

42. Cosmos Episode 6 “39:00 until the end”