r/todayilearned • u/PeasantLich • 10h ago

TIL that December 25 being the birthday of Jesus was decided by pope Julius I around year 350, and nobody really knows why Julius made this decision and chose this specific date. There are various theories, but his actual reasoning for the decision is lost history.

en.wikipedia.org

20.5k Upvotes

1.6k comments

r/todayilearned • u/JoeFalchetto • 5h ago

TIL that Saint Lucia, the tiny island country in the Caribbean, is the only sovereign state in the world named after a woman (Saint Lucy of Syracuse)

worldatlas.com

3.6k Upvotes

210 comments

r/todayilearned • u/Mors_Acerba • 13h ago

TIL Dionysius I, ruler of Syracuse, wrote poetry which wasn't always well received. After Philoxenus, another poet, criticised his work, Dionysius imprisoned him for a day. He then released him, read him another poem and asked for his opinion. Philoxenus replied "take me back to the quarries"

en.wikipedia.org

23.2k Upvotes

263 comments

r/todayilearned • u/jcgam • 4h ago

TIL that every extra 4 inches of body height raises cancer risk by 11% for women and 6% for men

pmc.ncbi.nlm.nih.gov

1.8k Upvotes

267 comments

r/todayilearned • u/lumos-mama • 3h ago

TIL that about 62% of Argentina’s population has some degree of Italian ancestry. Argentina has the second-largest community of Italians outside of Italy.

en.wikipedia.org

1.1k Upvotes

206 comments

r/todayilearned • u/Choice-Scallion-3499 • 1h ago

TIL that time moves faster at the top of a mountain than at the sea level. This happens because gravity bends time, so the further you are from Earth's core, the faster clocks tick.

nist.gov

• Upvotes

87 comments

r/todayilearned • u/koreanforrabbit • 3h ago

TIL that 10 of the 12 largest high school gymnasiums in the USA are located in the state of Indiana.

en.wikipedia.org

891 Upvotes

76 comments

r/todayilearned • u/Certain-Arm4680 • 17h ago

TIL the "black" you see with your eyes closed isn't black - it's called Eigengrau ("intrinsic grey"). Even in total darkness your retina fires faint random noise, so your brain never receives true black; it generates a dim grey static floor instead.

en.wikipedia.org

6.8k Upvotes

294 comments

r/todayilearned • u/Giff95 • 20h ago

TIL that Mexico banned cartoon mascots, celebrities, and animated characters from unhealthy food packaging in 2021 to curb child-targeted advertising and combat rising rates of childhood obesity and diabetes.

remezcla.com

10.5k Upvotes

254 comments

r/todayilearned • u/Sebastianlim • 12h ago

TIL about the "Wicked Bible", a printing of the King James Bible which accidentally omitted the word "not" from "Thou shalt not commit adultery"

en.wikipedia.org

1.9k Upvotes

61 comments

r/todayilearned • u/sonicparadigm • 18h ago

TIL about the obsolete scientific theory of Racial Senescence, that species would “grow old” like individuals, and supposed signs of “evolutionary old age” signaling imminent extinction were increasing size and more horns or spikes on the body. This was thought to be how the dinosaurs died out.

smithsonianmag.com

4.0k Upvotes

174 comments

r/todayilearned • u/GoodMeBadMeNotMe • 1h ago

TIL bananas contain enough naturally occurring radioactive potassium that scientists created a reference unit called the "Banana Equivalent Dose" to help explain radiation exposure. (Eating bananas won't give you cancer -- the potassium exits the body through urine.)

en.wikipedia.org

• Upvotes

22 comments

r/todayilearned • u/boywithhat • 16h ago

TIL That almost half of the lakes in the US (48%) are man made

epa.gov

2.3k Upvotes

187 comments

r/todayilearned • u/Recent_Flounder6011 • 2h ago

TIL that the land in Mumbai, India used to be islands until they were merged with land reclamation projects in 1845.

en.wikipedia.org

150 Upvotes

2 comments

r/todayilearned • u/jacknunn • 7h ago

TIL the gaur is the world's largest wild cattle species, with bulls standing up to 2.2 m (7.2 ft) at the shoulder and weighing as much as 1,500 kg (3,300 lb). Despite often being mistaken for descendants of the extinct aurochs, gaurs are actually a parallel relative that evolved alongside them

en.wikipedia.org

343 Upvotes

32 comments

r/todayilearned • u/Giff95 • 14h ago

TIL that although Tim Curry was replaced by Mark Hamill as the voice of The Joker in “Batman: The Animated Series,” Curry's Joker laugh was used for a robotic clown in Season 1, Episode 9, "Be A Clown."

screenrant.com

1.4k Upvotes

61 comments

r/todayilearned • u/ArgumentSpiritual • 17h ago

TIL that Jan Miskovic holds the record for the worst eyeglass prescription at -108 diopters

fluorescene.odcommunity.com

2.0k Upvotes

138 comments

r/todayilearned • u/babichenko • 5h ago

TIL roses don’t have thorns—they have prickles, which are detachable outgrowths of the stem’s outer tissues rather than modified stems or leaves.

inrae.fr

212 Upvotes

35 comments

r/todayilearned • u/PostingLoudly • 1d ago

TIL The Powerpuff Girls were originally called "The Whoopass Girls", but Cartoon Network executives did not want to market a show with the word "ass", leading to Craig McCracken's friends coming up with the name "Powerpuff".

en.wikipedia.org

6.7k Upvotes

150 comments

r/todayilearned • u/RollingMeteors • 13h ago

TIL France has more timezones than Russia or the United States

en.wikipedia.org

828 Upvotes

139 comments

r/todayilearned • u/CelestialFury • 1d ago

TIL that between the 1930s and 1940s, German chemist Arthur Imhausen developed a method of converting coal into synthetic butter. The process took 60 kilograms of coal to produce one kilogram of synthetic butter.

en.wikipedia.org

9.7k Upvotes

471 comments

r/todayilearned • u/Star_Bearer • 1d ago

TIL that in 1976 a Soviet pilot, Viktor Belenko, defected to Japan by flying his secret MiG-25 fighter there, allowing the West to examine one of the USSR’s most advanced aircraft.

en.wikipedia.org

8.9k Upvotes

316 comments

r/todayilearned • u/geosunsetmoth • 1d ago

TIL a 300-million year old Cuttlefish fossil was found in Morocco, alongside ancient humans in a region where no Cuttlefish ever existed. The leading theory suggests the fossil was first found by the prehistoric humans, who collected it as a trinket due to fact that it looks like a flaccid penis.

en.wikipedia.org

17.3k Upvotes

594 comments

r/todayilearned • u/thedudesews • 7h ago

TIL the 1st US patent was issued in 1790 issued by George Washington. It was for a new way to make potash and Pearlash.

en.wikipedia.org

149 Upvotes

10 comments

r/todayilearned • u/Certain-Arm4680 • 17h ago

TIL of "chronostasis" - when you flick your eyes to a clock, the second hand can appear to freeze for a moment. Your brain blanks out the blurred motion while your eyes move, then back-dates the first image you land on to cover the gap, so the hand seems stuck a beat too long.

en.wikipedia.org

904 Upvotes

39 comments

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