This is a must-have Christmas ornament for space fans: Buzz's Bootprint. On Nov. 28, 2023, the students of Earth to Sky Calculus launched it to the stratosphere onboard a cosmic ray research balloon.
 
The 4-inch disk traveled 109,111 feet above the Sierra Nevada mountains of California, experiencing near-vacuum, cosmic rays, and space-like cold. It comes with a red ribbon for hanging on your Christmas tree! You'll also receive a greeting card showing the ornament in flight.
 
Apollo 11 astronaut Edwin Aldrin photographed this footprint in the lunar soil as part of an experiment to study the nature of lunar dust and the effects of pressure on the surface. The dust was found to compact easily under the weight of the astronauts leaving a shallow but clear impression of the boots, characteristic of a very fine, dry material. The footprint image has also become one of the enduring symbols of the first visit to the Moon.