In the waning days of summer, sky-watchers can get an amazing view of our home galaxy, the Milky Way, in the evening skies.

When viewed away from city lights, it is visible as a faint hazy band stretching from east to west overhead. For those in brightly lit suburbs, binoculars can help spot swarms of faint stars strewn across the Summer Triangle pattern of stars high above our heads this time of the year. The Milky Way actually cuts right across the cross-shaped constellation Cygnus, the swan.

Our sun and its family of planets live inside this vast Frisbee-shaped disk that is home to about a hundred billion suns and stretches some hundred thousand light-years across. Yet, the Milky Way is only