SciencePhysics
The speed of light can no longer be measured more accurately, because the metre is defined as the distance light travels in 1/299,792,458 of a second.
The number is now true by definition.
Source
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More science facts
Science facts that sound like a prank until you read the source. Tardigrades survived ten days in open space, a strong enough magnet can float a live frog, and time runs measurably faster at your head than at your feet. Short, sourced and picked for the double take.
- A magnet can make a live frog float in mid-air.
- Time runs faster at your head than at your feet.
- Strip the empty space out of every human and we would fit in a sugar cube.
- Water can boil and freeze at the same instant.
- A uranium deposit in Gabon went critical on its own about 1.7 billion years ago and ran as a natural nuclear reactor, in pulses, for a few hundred thousand years.
- Cold War nuclear tests spiked the world's carbon-14, tagging every cell built afterwards.