Welcome to Stars, Galaxies, and the Universe Summer 2004

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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! (Whats
  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).

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Example 1 Xi Bootes (see it tonight)
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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!

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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

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Arcturus (bright star overhead) as an immigrant
from another galaxy
The Milky Way (and other galaxies) catch and
devour small galaxies
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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.
• Lets 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!)

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The Sloan Digital Sky Survey- on its way to
measuring 1 million galaxies

• Frothy nature of galactic matter
• DARK MATTER

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A better look
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This summer, well learn about all of this, but
first.Details from the Syllabus