They feature a mini gondola hanging from the bottom of a regular balloon which holds a small motor with a propeller, an Arduino Pro Mini, LEDs, an ultrasonic sensor and of course, a battery.

The Silver Queen Gondola travels 2.5 miles from the heart of Aspen to the 11,000-foot-high summit of Aspen Mountain. A sundeck and eatery greets visitors at the top of the mountain and makes for a ...