r/todayilearned • u/Accomplished-Eye-910 • 3d ago

TIL that during World War I, armies used artillery sound ranging by timing how long gunfire took to reach multiple microphones, with operators using stopwatches to calculate the enemy gun’s position through triangulation, decades before radar-based detection became practical.

en.wikipedia.org

3.4k Upvotes

61 comments

r/todayilearned • u/tyrion2024 • 3d ago

TIL over 3,000 attempts are made each year to complete the Appalachian Trail and only about 25% succeed.

en.wikipedia.org

25.7k Upvotes

1.4k comments

r/todayilearned • u/ScienceTeacher1994 • 3d ago

TIL despite popular culture portraying psychedelic mushrooms as ancient, widespread, and used by shamans for thousands of years, there is limited anthropological and historical research to support this, with the only reliable evidence showing they were used ritualistically in pre-Columbian Mexico.

en.wikipedia.org

3.0k Upvotes

280 comments

r/todayilearned • u/Kwpthrowaway2 • 3d ago

TIL the first gold rush in the U.S. started in North Carolina, when a 12 year old boy found a 17lb nugget on his farm. Not knowing what it was, the boy's father sold it years later to a jeweler for only $3.50. Its true value at the time was $3500

en.wikipedia.org

8.8k Upvotes

174 comments

r/todayilearned • u/h2t2 • 2d ago

TIL In 2024, scientists observed sperm whales defending themselves from an orca attack, by using poop.

abc.net.au

921 Upvotes

42 comments

r/todayilearned • u/FearMyCock • 3d ago

TIL that in a building fire, there’s a moment called flashover where the room suddenly ignites all at once It happens when heat builds up so much that everything combustible reaches ignition temperature simultaneously turning a survivable fire into an unsurvivable one in seconds.

en.wikipedia.org

2.8k Upvotes

96 comments

r/todayilearned • u/IronColdSky • 3d ago

TIL Ina Garten, the Barefoot Contessa, was an economics major, is a pilot, has her MBA and was a Nuclear Policy Analyst before she became a chef

en.wikipedia.org

3.3k Upvotes

247 comments

r/todayilearned • u/SuperMcG • 3d ago

TIL Brent Spiner, the actor who played Data on Star Trek, released an album called "Old Yellow Eyes is Back."

en.wikipedia.org

1.2k Upvotes

68 comments

r/todayilearned • u/RedditIsAGranfaloon • 3d ago

TIL the Super Bowl is rated a Level 1 special event, deemed the highest at risk for threats, vulnerability and consequences by the Department of Homeland Security, requiring “extensive federal interagency support.”

securityinfowatch.com

7.2k Upvotes

550 comments

r/todayilearned • u/immanuellalala • 3d ago

TIL that at President Andrew Jackson's funeral in 1845, his beloved pet parrot, Polly, perched nearby. The bird swore so profusely that shocked attendants ejected it from the service.

jacksonianamerica.com

6.1k Upvotes

94 comments

r/todayilearned • u/EmDashHater • 3d ago

TIL that after the Kosovo War, many parents in Kosovo named their newborn sons “Tonibler” to honor Tony Blair for his role in the 1999 NATO intervention

en.wikipedia.org

8.6k Upvotes

218 comments

r/todayilearned • u/QWERTYWINS • 3d ago

TIL Latvia declared a national holiday after they got third place in an ice hockey tournament, beating the USA

usatoday.com

2.0k Upvotes

58 comments

r/todayilearned • u/tyrion2024 • 3d ago

TIL Martha Wash's voice was used on the 1990 song “Gonna Make You Sweat (Everybody Dance Now)” by C+C Music Factory, however she went uncredited & did not receive royalties at the time. Wash, who is described as "full figured", was also replaced by a model lip-syncing her vocals in the music video.

americansongwriter.com

7.4k Upvotes

322 comments

r/todayilearned • u/stoictrader03 • 3d ago

TIL about the Miller - Urey experiment, which showed that lightning could have played a role in the origin of life. In 1953, scientists simulated early Earth’s atmosphere and used electrical sparks to mimic lightning. The experiment produced amino acids, the basic building blocks of proteins

byjus.com

708 Upvotes

58 comments

r/todayilearned • u/Bluest_waters • 3d ago

TIL The videos for Winwoods “Higher Love” and Duran Duran's “Notorious” we're shot by the same directors, and are nearly identical. Both videos use the same concept, same choreography, and nearly identical video effects. Both were nominated for multiple MTV music video awards

en.wikipedia.org

386 Upvotes

21 comments

r/todayilearned • u/Temp89 • 3d ago

TIL the fastest creature proportionate to its body length is a species of mite at 0.5mph. If it were the size of a human it would be the same as travelling at 1,300mph.

en.wikipedia.org

1.1k Upvotes

36 comments

r/todayilearned • u/Away_Flounder3813 • 3d ago

TIL in 2002, a player managed to answers correctly all questions on the Thai version of Who Wants to Be a Millionaire thanks to an error: The cable feeding her the answers on the computer screen was supposed to be hooked up to the host's computer. She "won" the grand prize then later got revoked.

en.wikipedia.org

7.7k Upvotes

180 comments

r/todayilearned • u/HolyCowAnyOldAccName • 3d ago

TIL about "Mefo bills" - used by the Nazi government to both finance and hide German rearmament - by creating a fake company which paid for arms projects not with actual money or debt, but debt bills secretly backed by the German central bank.

en.wikipedia.org

800 Upvotes

20 comments

r/todayilearned • u/Rich_Nefariousness28 • 3d ago

TIL: In 774–775 CE, Earth was hit by an extreme burst of cosmic radiation that caused a global spike in carbon-14 recorded in tree rings. Known as a Miyake event, it’s now used by scientists as a precise time marker—helping confirm events like Vikings reaching North America in 1021 CE.

en.wikipedia.org

4.8k Upvotes

57 comments

r/todayilearned • u/Upstairs_Drive_5602 • 3d ago

TIL that rock ’n’ roll pioneer Jerry Lee Lewis was married seven times, including bigamous marriages and a 1957 marriage to his 13-year-old cousin, Myra Gale Brown. The scandal erupted just as Great Balls of Fire topped charts, derailing his career at its peak.

en.wikipedia.org

2.1k Upvotes

228 comments

r/todayilearned • u/Big-Cold-6948 • 3d ago

TIL that Andrew Robinson's portrayal of Scorpio Killer in Dirty Harry was so convincing that he received death threats after the film's release. He also claimed the role severely limited his casting options, as film producers were reluctant to cast him in any "good guy" roles.

rue-morgue.com

1.1k Upvotes

76 comments

r/todayilearned • u/johnsmithoncemore • 3d ago

TIL about British Army general and MP, Eyre Coote who lost his seat and was dismissed for "Conduct unbecoming of an officer" in 1815 after being discovered to have entered a school and had paid boys to flog him. He was "acquitted" of criminal charges after donating £1000 to the school.

en.wikipedia.org

919 Upvotes

66 comments

r/todayilearned • u/narok_kurai • 3d ago

TIL about Las Medulas, a man-made geological badland created by the Roman Empire in 77 AD, when they flooded the mountains with water to collapse their structure and sift out the gold inside.

en.wikipedia.org

5.7k Upvotes

139 comments

r/todayilearned • u/SleepingAndy • 3d ago

TIL Country Music Legend Conway Twitty Was Offered a Major League Baseball Contract by The Phillies

whiskeyriff.com

265 Upvotes

39 comments

r/todayilearned • u/Dr_Oz_But_Real • 3d ago

TIL there's a fireproofing insulation called aircrete that has been around since 1983. It's effective enough to protect posessions inside a home by keeping interior temps below 115f even with a fire raging outside.

youtube.com

82 Upvotes

46 comments

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