15 Photos That Remind Us How Big the Universe Is
...and how small we are.
Photo: Ryan Deboodt, Oxalis.com.vn
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An explorer stands in the dark magnitude that is the Son Doong Cave in Phong Nha-Ke Bang National Park in Vietnam. The cave is so massive it's home to a jungle, has its own localized weather system and can fly a 747 though its largest cavern.