<p>when was the last time you looked at the stars to figure out where you were, or used the way a tree was growing to orient yourself on a hike? do you watch the waves when you're at the beach to see which way the tides are moving and how to make your way back to shore?</p> <p>this week on the #mems podcast, i chat with a harvard physics professor about his other passion besides minute particles: finding his way in the world.&nbsp;</p>