Albert Einstein never wore jewelry, but even he might make an exception for this!
 
This singular piece of relativistic neckwear flew to the edge of space on May 17, 2019, aboard an Earth to Sky Calculus cosmic ray balloon. At the apex of the flight, it was 117,454 feet above the Sierra Nevada mountains of central California. Each Black Hole Pendant comes with a greeting card showing the item in flight and telling the story of its journey to the edge of space and back.
 
The pendant flew alongside an array of X-ray/gamma-ray sensors. The students launch these sensors approximately once a week to monitor increasing levels of deep space radiation penetrating Earth's atmosphere. The students got great data, and the pendant experienced a wild ride with temperatures as low as -62 C, air pressures less than 1% of sea level, and cosmic rays 200 times stronger than on the planet below.