PPT-The Milky Way

The Greek philosopher Democritus 450370 BC proposed that the bright band on the night sky known as the Milky Way might consist of distant stars Aristotle 384322 BC however believed the Milky Way to be caused by the ignition of the fiery exhalation of some stars which were large numerous and close together and that the ignition takes place in the upper part of the atmosphere in the region of the world which is continuous with the heavenly motions The . (Resolved by Galileo). Milky Way:. Galactic Structure and Dynamics. Milky Way has spiral structure. . Galactic Bulge surrounds the Center. . Powerful radio source Sagittarius A at Center. C. ontains Super-Massive Black Hole . The Milky Way Galaxy. When you look into the hazy band of light across the sky, you are actually looking at our galaxy from the inside. While an awesome sight, you can only truly begin to see it if you get away from city lights on a moonless night. . Recap. Canvas homework: due on Wednesday. Lab this week: Galaxy Morphology. Campus Observatory. Milky Way galaxy. Stars: . brightnesses. , masses, sizes, compositions, evolution. Interstellar matter: gas, dust. Galaxy. part 2. Unit: . Galaxies. Star systems like our Milky Way. Contain a few thousand to tens of billions of stars.. Large variety of shapes and sizes. Galaxy Diversity. The Hubble Deep Field:. William Herschel’s map of the Milky Way based on star counts. In the early 1800’s William Herschel, the man who discovered the planet Uranus, tried to understand the shape of the Milky Way by counting stars. He counted how many stars there were in each of dozens of different directions and then plotted the count versus direction. . 23.1 Our Parent Galaxy. 23.2 Measuring the Milky Way. Early “Computers”. 23.3 Galactic Structure. 23.4 The Formation of the Milky Way. 23.5 Galactic Spiral Arms. Density Waves. 23.6 The Mass of the Milky Way Galaxy. The Milky Way: Our Home Galaxy. What are the different. components of the Milky Way?. How do we see those components?. What does a map of each component look like from our point of view?. Stars in the Milky Way. Aug. 24 -- 10am class. Turn in HW 1 in the front of the room. If you didn’t get HW 1 on Monday, turn it in on Friday.. If you didn’t get the telescope lab on Monday, pick it up from Johanna.. . Loners. Interactions were once . believed to be unimportant . and rare.. Galaxies were thought to . be . isolated loners. , well . separated from one . another . a. nd scarcely interacting.. Au Contraire!. Spiral Structure. . The Astronomical Context. By the 1920’s, we knew that the once-mysterious spiral nebulae were flattened galaxies. . Our Milky . Way is . also. flattened. . Two obvious . questions arose:. bye:. Angelina Battle. The legend of The Milky Way. This is what old people told me when I was a child. Long ago, when the world was new, there were not many stars in the sky. In those days people depended on corn for their food. They would grind it and keep it in bins behind their homes. Bread made from cornmeal, often kept them from starving during the long winter months. . Chapter . 13, . Sections . 1. -5,7 (12 . pages). Homework for Next Time: . www.galaxyzoo.org. Question. Which of these is a picture of the Milky Way?. A. B. D. C. The Milky Way. Angular Size. Andromeda: MW’s Sister Galaxy. David Spergel. What has changed?. Context:. Standard cosmological model. No galaxy is an island… (John Dunne vs. Immanuel Kant). Tools:. Statistical galactic astronomy. 100s of stars -> 100,000s -> 1e9 (GAIA +LSST). László Dobos, Tamás Budavári, Carrie Filion,. Rosie. Wyse, Alex Szalay. Dept. . of . Physics. & . Astronomy. , The . Johns. Hopkins University. Subaru . Prime. . Focus. . Spectrograph. Manua.