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How Many Trees Are There?
S4 E78 / 4m 15s
It may be an impossible questions, but we can at least get close.
Join Joe Hanson as he explores curiosity and illuminates the science behind… well, everything.
Video description: It never gets dark anymore. Not REALLY dark, anyway. Not like it used to. Light pollution is not only making it more difficult to see the night sky, but it's also affecting our health. For the past century and a half, since the dawn of electric light, we’ve been losing our connection to the night. We need artificial light for modern society, of course.