Human Journey

The Kilogram’s New Diet Plan


Environmental contamination, and not the holiday season, has caused the International Prototype Kilogram to put on some extra pounds over the decades. Scientists are now looking for a safe and reliable method of cleaning the cylinder so that its mass remains stable and equal to that of several dozen copies around the world.

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Researchers, conservationists, and others share stories, insights and ideas about Our Changing Planet, Wildlife & Wild Spaces, and The Human Journey. More than 50,000 comments have been added to 10,000 posts. Explore the list alongside to dive deeper into some of the most popular categories of the National Geographic Society’s conversation platform Voices.

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