Bones of the Milky Way

"We have peered far into the Universe and vastly expanded our knowledge of distant realms. But interestingly enough, we are still refining our understanding of our own place within our galaxy, the Milky Way. Research into this question follows in the footsteps of many great names in astronomy: from Herschel to Hubble, and from Kapteyn to Kant, generations of astronomers helped to establish our understanding of our place in space."

Read More: http://www.calacademy.org/explore-science/bones-of-the-milky-way