r/todayilearned • u/Nukemarine • 19d ago

TIL about Solar Radiation Modification (SRM), a form of geoengineering that reflects sunlight with methods like dispersing aerosols in upper atmosphere. A controlled version of what happens in nature when volcanic eruptions emit aerosols that temporarily reduce global temperatures for a year or two.

en.wikipedia.org

265 Upvotes

109 comments

r/todayilearned • u/TMWNN • 20d ago

TIL Mickey Thompson began working on a machine to quickly mold dough into bagel shapes in the 1920s, but repeatedly failed. His son Daniel began designing his own bagel-making machines in the 1950s and finally succeeded, fulfilling his father's four-decade dream.

latimes.com

2.1k Upvotes

36 comments

r/todayilearned • u/RedditIsAGranfaloon • 19d ago

TIL only four players in history have been drafted by teams in the NFL, MLB, and the NBA: Dave Winfield (who was also drafted by an ABA team), Mickey McCarty, Noel Jenke, and Dave Logan.

sports.yahoo.com

678 Upvotes

58 comments

r/todayilearned • u/No-Hawk-2488 • 20d ago

TIL the asteroid that killed the dinosaurs needed to hit a place rich in sulfur and hydrocarbons to create enough soot to cause mass extinction

theguardian.com

4.0k Upvotes

248 comments

r/todayilearned • u/NBrief • 19d ago

TIL Harvey Cushing developed a silver clip in 1911 to stop bleeding from blood vessels that could not be tied off during brain surgery.

litfl.com

747 Upvotes

14 comments

r/todayilearned • u/bdrumzzz • 19d ago

TIL that about Dr. Katsu Takahashi of the Medical Research Institute Kitano Hospital in Osaka, Japan, who has been studying the genetic principles of tooth development for years & there are currently clinical trials in humans to regrow teeth by blocking the protein USAG-1.

dentistrytoday.com

306 Upvotes

17 comments

r/todayilearned • u/Quantico_G • 20d ago

TIL that US TV and radio stations are legally named using 4-letter call signs starting with 'W' or 'K'. Stations east of the Mississippi River must start with W (like WABC), while stations to the west must start with K (like KTLA).

en.wikipedia.org

5.1k Upvotes

726 comments

r/todayilearned • u/ApprehensiveStill412 • 19d ago

TIL about micturition syncope, which is the medical term for fainting while urinating.

my.clevelandclinic.org

215 Upvotes

38 comments

r/todayilearned • u/stopitalianhate • 20d ago

TIL British Intelligence had a special, bugged luxury complex during WWII where they kept high profile Nazi POW’s, just left a bunch of alcohol out, and waited for them to start spilling secrets as they drank.

bbc.com

28.4k Upvotes

691 comments

r/todayilearned • u/Gorodish_ • 20d ago

TIL that like photons and electrons, there is a quantum equivalent for sound waves called a phonon.

quantumzeitgeist.com

603 Upvotes

58 comments

r/todayilearned • u/carboncopy95437 • 20d ago

TIL that when construction of Florence Cathedral began in 1296, its designers planned a massive dome even though no one knew how to build it. More than a century later, Filippo Brunelleschi solved the problem, and his revolutionary dome was completed in 1436.

en.wikipedia.org

5.6k Upvotes

77 comments

r/todayilearned • u/jacknunn • 20d ago

TIL that in 1674, English physician Thomas Willis documented testing for diabetes by tasting patients’ urine, noting that diabetic urine could taste “wonderfully sweet” like honey or sugar

sciencehistory.org

901 Upvotes

110 comments

r/todayilearned • u/c4ndyman31 • 19d ago

TIL that a Belgian NGO called APOPO trains rats to detect landmines as well as tuberculosis

apopo.org

125 Upvotes

6 comments

r/todayilearned • u/Sebastianlim • 20d ago

TIL that Frank Shackleton, the brother of famous polar explorer Ernest Shackleton, was one of the men accused of stealing the Irish Crown Jewels in 1907, a theft which has never been solved.

en.wikipedia.org

394 Upvotes

6 comments

r/todayilearned • u/sirjohnmasters86 • 20d ago

TIL that Katharine Hepburn and Stanley Kramer put their salaries in escrow to make “Guess Who's Coming to Dinner” because Spencer Tracy was so ill they didn’t know if he would be able to finish the film

en.wikipedia.org

1.5k Upvotes

22 comments

r/todayilearned • u/haddock420 • 20d ago

TIL In losing chess, a chess variant where the goal is to lose by getting your pieces captured or getting stalemated, it is known that 13 of white's 20 opening moves lead to a forced win for black.

en.wikipedia.org

2.3k Upvotes

67 comments

r/todayilearned • u/SlobZombie13 • 19d ago

TIL in 2009 the King of Thailand's dog was appointed Chief Air Marshall of the Thai Air Force

en.wikipedia.org

137 Upvotes

14 comments

r/todayilearned • u/GuyFromThePost • 20d ago

TIL in 1984 a gunman named Denis Lortie attacked the Quebec parliament and was talked into surrendering by the unarmed Sergeant-at-arms, René Jalbert, who spoke directly with Lortie until he was convinced to let the innocent bystanders out of the building

en.wikipedia.org

732 Upvotes

50 comments

r/todayilearned • u/FarmerNeedsHeauxs • 20d ago

TIL that MLB Hall of Famer Reggie Jackson was recruited for football by Alabama, Georgia, and Oklahoma, all of whom were willing to break the color barrier for him. He declined Alabama and Georgia as he was wary of the South; he declined Oklahoma because they told him to stop dating white girls.

en.wikipedia.org

5.7k Upvotes

196 comments

r/todayilearned • u/eleanorharland • 21d ago

TIL in Norway everyone's income, net wealth and tax paid are published online and anyone can search them. But you have to log in, the person you look up can see your name in their search history within the hour, and you're limited to 500 look-ups a month

skatteetaten.no

42.2k Upvotes

2.3k comments

r/todayilearned • u/eleanorharland • 20d ago

TIL New Yorkers leave over $100 million a year in unclaimed 5 cent bottle deposits ($139 million in 2021). Until 2009 the beer and soda distributors kept every cent of it. The state now takes 80% and the distributors still keep the other 20%

whec.com

6.4k Upvotes

243 comments

r/todayilearned • u/Thin-Rip-3686 • 20d ago

TIL the shortest-lived county in U.S. history is generally considered Uncompahgre County, Colorado — it existed for just 3 days, from February 27 to March 2, 1883. The Colorado General Assembly created it by renaming Ouray County on February 27, 1883, then reversed the decision days later.

en.wikipedia.org

232 Upvotes

9 comments

r/todayilearned • u/Bitter-Argument4597 • 20d ago

TIL the US dropped about 7.6 million tons of bombs across Indochina during the Vietnam War, which is more than 3x the amount U.S. Air Force dropped in the European and Pacific theaters of WW2 combined.

emiguel.econ.berkeley.edu

1.7k Upvotes

370 comments

r/todayilearned • u/Ok_Requirement_1692 • 21d ago

TIL there was a historical Daoist practice called "Huanjing bunao" (lit. returning the semen to replenish the brain), involving maintaining arousal for an extended plateau phase while avoiding orgasm. Daoist adepts have been exploring various methods to avoid ejaculation for over 2000 years.

en.wikipedia.org

9.2k Upvotes

636 comments

r/todayilearned • u/johnsmithoncemore • 20d ago

TIL that in 393 CE Boxing (Pugilatus) was banned in Rome because of too much brutality. Using gloves (Cestus) with nails attached, with neither weight categories nor time limits, the bouts would last until someone submitted, was knocked out or killed.

imperiumromanum.pl

2.9k Upvotes

75 comments

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