Curated OER
Galaxies and the Universe
If Earth was formed 4600 million years ago, and the sun revolves about the center of the Milky Way once every 250 million years, how many revolutions have occurred? Students answer this question and ten more, all providing students with...
Curated OER
How Many Stars in the Milky Way?
Students perform an experiment in which they will use a statistical method called `sampling' to count to a billion (and beyond). Students practice sampling by estimating the number of characters on a page from the classified section of a...