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Join us on a fascinating exploration of stars, galaxies, and the universe. Learn about binary stars, alien stars like Arcturus, dark matter, and the texture of the universe. Discover the Milky Way and other galaxies and delve into the latest research findings. Get ready for an incredible summer course!
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Welcome to Stars, Galaxies, and the UniverseSummer 2004 • Initial pleasantries, who I am, who you are • This should be the most interesting course you take in college • Example 1(very basic): the star Xi Bootes in the night sky • Example 2: Arcturus as an alien star! (What’s that mean?) • Example 3: the texture of the universe and the presence of the dark matter (state of the art, up-to-the minute research results).
Some of the facts about Xi Bootes • A binary star • Components G5V and K4V stars • Apparent magnitudes 4.8 and 7.0 • Separation of pair = 6.4 arcseconds • A good lab project!
All the above meaningless gibberish now, but By the end of the semester, you will recognize that this tells you: The types of stars (the brighter one is like the Sun) The distance to the system The fact that it verifies the “mass luminosity relation” The distance between the two stars
Arcturus (bright star overhead) as an immigrant from another galaxy The Milky Way (and other galaxies) catch and devour small galaxies
The form (or texture) of the universe as a whole (?!) • We will learn that the Milky Way is a system (galaxy) of about 200 billion stars • Galaxies are sprinkled through space at a density of about one every megaparsec or so. • Let’s see how they are distributed on extremely large scales. • In the last few years, new data has been arriving to illuminate this (and not only from the HST!)
The Sloan Digital Sky Survey- on its way to measuring 1 million galaxies “Frothy” nature of galactic matter “DARK MATTER”
This summer, we’ll learn about all of this, but first….Details from the Syllabus