One unbelievable fact. Three guesses. Archive →
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2026-09-10
Polar bear fur looks white. What is it actually like up close?
2026-09-09
About how deep is Challenger Deep in the Mariana Trench, the deepest known point in the ocean?
2026-09-08
About how big is a blue whale's heart?
2026-09-07
The 1883 Krakatoa eruption produced what is often called the loudest sound in recorded history. How far away was it still heard as a boom?
2026-09-06
Lab experiments simulating Uranus and Neptune suggest what bizarre kind of weather deep inside those planets?
2026-09-05
The adult human brain is about 2% of body weight. Roughly what share of the body's resting energy does it use?
2026-09-04
About how often does the International Space Station complete one orbit of Earth?
2026-09-03
Which is hotter: a typical lightning bolt, or the visible surface of the Sun?
2026-09-02
If you had a bathtub big enough, which planet would float because its average density is less than water?
2026-09-01
About how much would a teaspoon of neutron-star material weigh on Earth?
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