Sec. 4 Star Systems & Galaxies YouTube video-Bill Nye Galaxies song
Discover Activity-Why Does the Milky Way Look Hazy?
Using a pencil, carefully poke at least 20 holes close together in a sheet of white paper.
Tape the paper to a chalkboard or dark-colored wall.
Go to the other side of the room and look at the paper. From the far side of the room, what do the dots look like? Can you see individual dots?
Think It Over
Making Models How is looking at the paper from the far side of the room like trying to see many very distant stars that are close together? How does your model compare to the photograph of the Milky Way below?
Densely packed w/ stars Made of few thousand stars Older stars about same age & distance from Earth Have bright supergiants & much gas & dust Round Loose, disorganized appearance Globular clusters Open clusters