Science & TechFact

The sunlight on your skin is eight minutes old.

Light travels through vacuum at exactly 299,792,458 metres per second. That number isn't measured, it's fixed: since 1983 the metre has been defined by it. Sunlight needs about 8 minutes and 20 seconds to reach Earth, moonlight about 1.3 seconds. Nothing in nature moves faster.

Useful: Looking at the night sky means looking into the past: stars appear as they were years or millennia ago.

Source: en.wikipedia.org

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