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Leonardo da Vinci (1452-1519), Italian Renaissance painter from Florence. Engraving by Cosomo Colombini (d. 1812) after a Leonardo self portrait. Ca. 1500.

10 Famous Artworks by Leonardo da Vinci

American bison (Bison bison) also known as buffalo or plains buffalo on the prairie, western U.S.

What’s the Difference Between Bison and Buffalo?

Ahura Mazda - relief of the Zoroastrian god Ahura Mazda at the ancient ruins of Persepolis in Iran. Also known as Ormazd Zoroastrianism,

Which Religion Is the Oldest?

Bog body. Head of Tollund Man. Died at about age 30-40, Dated to about 280 BCE early Iron Age. Found Bjaeldskovdal bog Denmark in 1950 near Elling Woman. Most well preserved bog body to date. Human remains mummified in natural peat bogs. mummy, embalm

9 Noteworthy Bog Bodies (And What They Tell Us)

Nativity Scene, Adoration of the Magi, Church of the Birth of the Virgin Mary, Montenegro

Why Is Christmas in December?

Black widow spider

9 of the World’s Deadliest Spiders

Mount Everest (Mt. Everest, mountains, Himalayas).

Is Mount Everest Really the Tallest Mountain in the World?

SI second

unit of time

Learn about this topic in these articles:

time

In time: SI second
The CGPM redefined the second in 1967 to equal 9,192,631,770 periods of the radiation emitted or absorbed in the hyperfine transition of the cesium-133 atom; that is, the transition selected for control of the cesium-beam clock developed at the National Physical Laboratory. The…
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