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It's a far-out gift for the cat-lover in your life: The Planet Cat Pendant. The sterling silver jewelry touched space on April 29, 2023, when it hitched a ride onboard an Earth to Sky Calculus cosmic ray research balloon. At the apex of the flight it floated 113,780 feet above the snow-capped Sierra Nevada Mountains of central California.


During the 2.75  hour flight, the pendant experienced temperatures as low as -63 C and air pressure less than 0.2% of sea level. Cosmic ray levels soared to 100x Earth-normal! After onboard sensors gathered enough radiation data, the payload parachuted back to Earth, landing on the west slope of the Inyo Mountains near Bishop, California.


The students of Earth to Sky Calculus are selling space pendants to support their cosmic ray ballooning program. Each one comes with a greeting card showing the pendant in flight and telling the story of its journey to the stratosphere and back again.

Planet Cat Pendant

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