In Arizona, during the heat of summer we would head for the mountains. We knew dozens of fire roads and meadows where a telescope could be set up under the stars among the cool forest pines. When the weather chilled, we headed to the low desert, our favorite site was Sentinel, Arizona. A desolate volcanic field just off Interstate 8 between Gila Bend and Yuma. It was still cool at night, a beautiful place to enjoy the desert skies…