When you gaze up at the night sky, all the stars you see are part of our own Milky Way galaxy. The Milky Way holds 100 to 400 billion stars! Learn about how galaxies form, the perplexing mysteries of black holes, and how galaxies can differ from one another with science expert Velma and the rest of the Scooby-Doo gang.
ThriftBooks sells millions of used books at the lowest everyday prices. We personally assess every book's quality and offer rare, out-of-print treasures. We deliver the joy of reading in recyclable packaging with free standard shipping on US orders over $15. ThriftBooks.com. Read more. Spend less.