1. Cosmology Equipped with his five senses, man explores the universe around him, and calls the adventure "science". -- Edwin Powell Hubble

2. Distance scales Cosmic Distance Scale

3. Hubble’s Measured Rate of Expansion v=H 0 r H 0 =72 km/(sec Mpc)

4. The Big Bang Framework CMB Redshift z = 1089 Quasar Redshift z= 6.4 Change in size of space = z+1

5. Key Observations Explained "NASA/WMAP Science Team” http://map.gsfc.nasa.gov/m_mm.html CMRB temperature and lumpiness flatness of space

6. Large Scale Structure The distribution of galaxies in a slice of the SDSS spectroscopic survey. (A. Pope, JHU http://cas.sdss.org/dr2/en/astro/structures/structures.asp)

7. Geometry of Space But how is the rate of expansion changing? Astronomers set out to measure the recessional velocities of very distant objects to find out how the expansion rate may be changing. If space is flat and the universe is dominated by matter, our rate of expansion should be slowing down. closedopenflat expansion

8. Evidence for Acceleration

9. An Accelerating Universe

10. Best Model of Mass-Energy Density 4% Visible matter 23% Dark Matter 73% Dark Energy !