Stargazing is best done by star-hopping, not apps. (Image credit: Mariyariya via Getty Images) "Look, there's the Southern Cross !" I turned, expecting an outstretched arm and a finger pointing low to the horizon. Instead, she was pointing at her phone. Her friend hurried over, not to look up, but to look down — both of them staring at a glowing screen while, just beyond them, Crux was visible in the night sky. I wanted to interrupt them, to redirect their attention by a few degrees. Just lift your eyes! It's right there! You don't need to try to recognize everything in the night sky at once. Beginners often miss this and try to match the entire sky to a chart on a phone. It doesn't work because the sky is too big. To know it, you have to navigate it, starting with something obvious and moving to something less so, building a chain and, in time, a mental map. The night sky will reveal itself to you slowly if you let it, and it will be with you the rest of your life.…