curio

Where Curio's facts come from

130 of the 147 cards published on Curio link to a source, across 94 sites. 17 do not, and are listed nowhere on this page — a card with no source says so by saying nothing.

Grouped by site, most-cited first. Every card below links to its own page, and that page links to the source itself. Reference sources such as Wikipedia are labelled rather than presented as primary evidence; cards without a source are excluded from this ledger.

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en.wikipedia.org22 cardsreference, not primary

• Can you really see the Great Wall of China from space?
• Did Vikings really wear horned helmets?
• Each of your eyes has a blind spot. Why don't you notice it?
• How a melted candy bar led to the microwave oven
• How a terrible smell forced London to rebuild its sewers
• The cook who survived 60 hours at the bottom of the sea
• The park ranger struck by lightning seven times
• The soldier who kept fighting World War II until 1974
• The war that lasted about 40 minutes
• What did Nintendo sell before video games?
• What do the letters OUOSVAVV on an English stone monument mean?
• What kept a stranded sailor fed for 133 days on a raft?
• Where did the word "OK" come from?
• Who hijacked two Chicago TV broadcasts with a masked figure in 1987?
• Who was the unknown man found on an Australian beach?
• Why do we always see the same side of the Moon?
• Why do you feel your phone buzz when it didn't?
• Why do you get goosebumps when you're cold?
• Why do you suddenly see something everywhere once you notice it?
• Why does dropped toast so often land butter-side down?
• Why does eating ice cream fast make your forehead hurt?
• Why some color copying machines refuse to copy paper money

pubmed.ncbi.nlm.nih.gov8 cards

• A mirror helped some people unclench a missing hand
• How patients with severe memory loss pictured a game they'd forgotten playing
• Learning a skill can reveal mistakes you missed
• Tiny animals survived outside a spacecraft without air
• Were woolly mammoths, hairy elephant relatives, alive when Egypt built the Great Pyramid?
• Why chili peppers burn your mouth but not a bird's
• Would everyone remember your embarrassing T-shirt?
• You can like an image without remembering seeing it

pmc.ncbi.nlm.nih.gov4 cards

• A wrong guess can become part of your next memory
• How do monarch butterflies steer by the sun all day?
• How does a panther chameleon really change color?
• Why are you taller in the morning than at bedtime?

brainfacts.org2 cards

• How someone can talk during brain surgery
• Why can't you tickle yourself?

consumerfinance.gov2 cards

• Small payment plans can add up to a big bill
• Why paying $25 can reduce your card debt by only $5

journals.sagepub.com2 cards

• Can choosing a laptop make it look better in your memory?
• Why a camera can seem better when a pricier one appears

nps.gov2 cards

• This frog survives ice inside its body and a stopped heart
• Why American and British troops faced off over one dead pig

plato.stanford.edu2 cards

• If every piece of a ship is replaced, is it still the same ship?
• The simplest explanation can still be wrong

access-board.gov1 card

• Why an elevator may ignore the close button for a few seconds

antarctica.gov.au1 card

• A penguin stays warm by letting its feet stay cold

aol.com1 card

• What was Play-Doh first made for?

archive.nyu.edu1 card

• An ancient library could lose texts without a fire

ars.usda.gov1 card

• Why does a freshly cut apple turn brown?

arxiv.org1 card

• Why hot water sometimes gets a freezing head start

ask.ifas.ufl.edu1 card

• Rain under this tree can leave blisters on your skin

asm.org1 card

• Why leafcutter ants carry leaves they don't eat

au.schindler.com1 card

• Elevator mirrors can help wheelchair users back out

australian.museum1 card

• A coffin inventor added a bell—and an escape ladder

beinecke.library.yale.edu1 card

• The strange old book nobody can reliably read

blogs.loc.gov1 card

• Why are so many old barns painted red?

brown.edu1 card

• Why a belly flop hurts when water can move aside

buildingslack.com1 card

• How a failed online game turned into the work chat app Slack

canadianmysteries.ca1 card

• An Arctic crew’s note: “All well.” Later: 24 dead.

cdn.who.int1 card

• Why surgery teams say the basic checks out loud

cloudflare.com1 card

• A saved website copy can load fast but show old information

deremilitari.org1 card

• Cannons broke a city wall. Defenders filled the gap with barrels.

desy.de1 card

• Why does a mirror flip left and right, but not up and down?

dynamics.berkeley.edu1 card

• Why a shoelace can hold for ages, then suddenly come undone

en.wikisource.org1 card

• Why a wealthy Roman suggested living with less

encyclopediaofalabama.org1 card

• What bruised an Alabama woman napping on her sofa in 1954?

epa.gov1 card

• Why your banana is slightly radioactive

epi-snow.ph.ucla.edu1 card

• The clue that linked London deaths to one water pump

esf.edu1 card

• Where do autumn leaves get their yellow color?

eta-publications.lbl.gov1 card

• Why a solar farm can wait years to connect to the power network

exhibits.library.cornell.edu1 card

• What was the board game that became Monopoly first meant to teach?

experts.illinois.edu1 card

• Would you notice a stranger asking directions swapped for a different man?

experts.umn.edu1 card

• Why unfinished work can distract you from the next task

exploratorium.edu1 card

• Why a pressure cooker makes boiling water extra hot

extension.psu.edu1 card

• Why honey lasts so long—and why the lid matters

gc.soton.ac.uk1 card

• Why a new road can bring more cars

guinnessworldrecords.com1 card

• A flight attendant survived a fall inside a broken plane

gutenberg.org1 card

• A politician won over a rival by borrowing a book

gwern.net1 card

• Why an even $20 bet might feel like a bad deal

heritagecollections.parliament.uk1 card

• Britain banned the slave trade without freeing enslaved people

hgc.com.hk1 card

• Backup internet cables can fail if they share the same route

home.csulb.edu1 card

• Would the rules seem fair if you might end up poor?

home.nps.gov1 card

• TV showed Americans police attacking voting-rights marchers

hu.gatech.edu1 card

• Wombats make square poop inside a round intestine

iop.uva.nl1 card

• Why is ice so slippery?

jnd.org1 card

• If everyone presses the label, maybe it looks like a button

journals.plos.org1 card

• Thin ice pushed heavy rocks across a desert lakebed

lavi.com1 card

• Why one checkout line can be fairer than choosing your own

lexundria.com1 card

• Why ancient Rome put a tax on collected urine

mit.edu1 card

• The bat-and-ball puzzle with a tempting wrong answer

mnhs.org1 card

• What use was a glue that peeled right off?

mothership.sg1 card

• Why does a skyscraper keep a giant steel ball near its top?

naa.gov.au1 card

• Australia sent machine guns to fight crop-eating birds

nasa.gov1 card

• The explosion that flattened a forest without making a crater

ncpedia.org1 card

• Where did the English settlers who vanished from Roanoke Island go?

news.gallup.com1 card

• “Make the report better” can send two coworkers in opposite directions

news.uchicago.edu1 card

• Does the cartoon creature Pikachu have a black-tipped tail?

niddk.nih.gov1 card

• How your gut keeps food moving without instructions from you

ocean.si.edu1 card

• Shark ancestors are older than the earliest known forests

oceanexplorer.noaa.gov1 card

• How an ocean map can miss an underwater mountain

openstax.org1 card

• Why water needs soap to carry grease away

paulgraham.com1 card

• Stripe’s founders set up payment software on customers’ laptops

pratt.duke.edu1 card

• This frog hides its red blood cells while it sleeps

press.uchicago.edu1 card

• Did tulip trading really bankrupt the Netherlands?

publicdomainreview.org1 card

• How three officials survived being thrown from a high window of Prague Castle

rintintin.colorado.edu1 card

• Would a perfect life count if none of it really happened?

rmg.co.uk1 card

• The crew had vanished. The ship’s small boat was gone too.

royalsocietypublishing.org1 card

• How one cuckoo chick gets fed like a whole nest

sarabethbuckley.wordpress.com1 card

• A city tried to cure nonstop dancing with more dancing

science.nasa.gov1 card

• How a mathematician pinpointed the planet Neptune before anyone knew it existed

sciencedaily.com1 card

• How can an owl twist its head so far without cutting off blood?

sciencedirect.com1 card

• “Smashed” changed how people described a car crash

sec.gov1 card

• A profitable sale can still leave a business short of cash

sfmuseum.org1 card

• How San Franciscans treated a penniless man who declared himself emperor

sites.lsa.umich.edu1 card

• Why someone may crave a drug they no longer enjoy

sparq.stanford.edu1 card

• A longer medical test left a less painful memory

startalkmedia.com1 card

• A stranded astronaut needs food before his potatoes are ready

text-message.blogs.archives.gov1 card

• The glowing watch paint that poisoned its painters

text.npr.org1 card

• How sunken stone money stayed spendable on the Pacific island of Yap

theconversation.com1 card

• Sunlight makes the Eiffel Tower lean slightly away

toureiffel.paris1 card

• Radio helped save the Eiffel Tower from being taken down

tshaonline.org1 card

• Why the gas for your stove smells like rotten eggs

ucl.ac.uk1 card

• How ancient gears tracked the Moon and predicted eclipses

ursulakleguin.com1 card

• Would you leave a happy city built on one child’s suffering?

usgs.gov1 card

• Why a calm lake in Cameroon released a deadly cloud in 1986

van.physics.illinois.edu1 card

• Why does metal feel colder than wood in the same room?

w2.eff.org1 card

• The hidden yellow dots some color laser printers add to their pages

w4.stern.nyu.edu1 card

• Why do so many prices end in .99?

warmuseum.kyiv.ua1 card

• A bird built its nest with cable used to control war drones

www1.eere.energy.gov1 card

• Why won’t a fan cool an empty room?