Book 6 Sources

1 What is the Great Attractor?

Space.com – Will the Great Attractor Destroy Us? Wikipedia – Great Attractor Wikipedia – Shapley Supercluster Wikipedia – Laniakea Supercluster Universe Today – What is the Great Attractor? Medium – The Powerful and Mysterious Great Attractor Wikipedia – Norma Cluster Wikipedia – Zone of Avoidance Forbes – Measuring the Speed of Our Galaxy ESA – Cosmic Microwave Background Astronomy.com – Why Will the Milky Way and Andromeda Collide?

2 How can giraffes have such long necks?

Creation.com – Giraffe Neck Design Giraffe Conservation – Why Do Giraffes Have Long Necks? New York Times – Giraffe Neck Evolution Wired – Why Do Giraffes Have Long Necks? Wikipedia – Giraffe SV-POW – Giraffe and Human Metacarpals Compared

3 When did people start using nails?

Designing Buildings – History of Nails Monroe Engineering – Nailed It: The History of Nails InspectAPedia – Dating Nails and Hardware Wikipedia – Nail (Fastener) Outdoor Revival – Pegged Wood Construction Wikipedia – Animal Glue NPS – Watch Those Thumbs Britannica Kids – Bronze Age History.com – Iron Age

4 What is the immortal hydra?

YSJournal – The Immortal Hydra PNAS – Hydra Regeneration Study Smithsonian – How Hydras Regrow Heads DW – Anti-Aging Secret of Hydras LiveScience – Hydra Regeneration Map Karger – FOXO3 Longevity Gene

5 Where did the Democratic and Republican parties come from?

LiveScience – Origins of U.S. Political Parties WhiteHouse.gov – George Washington Wikipedia – Continental Congress American Corner – Political Unity History.state.gov – Declaration of Independence Wikipedia – President of the Continental Congress Britannica – Washington’s Political Party Digital History – Political Parties Lesson Britannica – Democratic-Republican Party Wikipedia – Federalist Party Wikipedia – Democratic-Republican Party Dictionary.com – Democrats vs. Republicans Library of Congress – Formation of Political Parties

6 When did people start using soap?

New York Times – Soap and Handwashing Farmers’ Almanac – The History of Soap Medium – How Soap Works Wikipedia – Hydroxide Wikipedia – Alkali Metal Wikipedia – Lye Raven’s Roots – Making Lye Britannica – How Soap Works Time – Origins of Soap Wikipedia – Soap Cleaning Institute – History of Soaps and Detergents

7 What is the difference between a castle, a fort, and a palace?

World Atlas – Castles, Palaces, and Forts Wikipedia – Fortification English Heritage – Castles Through Time Twinkl – Castle Facts Wikipedia – Castle Family Handyman – Castle vs. Palace Wikipedia – Palace Wikipedia – Palatine Hill

8 What is botulism?

NHS – Botulism Overview Wikipedia – Clostridium botulinum USDA – Clostridium botulinum Wikipedia – Botulinum Toxin WHO – Botulism Fact Sheet Frontiers – Clostridium Botulinum Research Wikipedia – Botulism NCBI – Botulism Research Article

9 Do the gulags still exist?

Gulag Online – History of the Gulag Wikipedia – Gulag Wikipedia – Katorga Eurozine – The Gulag is Still Alive Reuters – Navalny and Modern Gulags History.com – Gulag History Library of Congress – Russian Discovery of Siberia Carnegie Moscow – Ending Feudalism in Russia Wikipedia – Federal Security Service

10 Why do some trees make rubber?

PNAS – Rubber Biosynthesis in Plants The Daily Garden – What is Latex? Treehugger – Where Does Latex Come From? USDA – Latex in Plants Frontiers for Kids – Rubber from Plants AOCS Lipid Library – Rubber Biosynthesis Wikipedia – Natural Rubber Wikipedia – Latex RIKEN – Plant Latex Research Science News Explores – What are Polymers?

11 What is the difference between socialism and communism?

Byju’s – Communism, Capitalism, and Socialism Investopedia – Communism vs. Socialism History.com – Differences Between Socialism and Communism Wikipedia – Communism Wikipedia – Socialism Investopedia – Socialism Definition Investopedia – What is a Socialist Economy? AIER – What’s Wrong with Communism?

12 How does cacao become chocolate?

Holland & Barrett – Introduction to Cacao Powder Science of Cooking – How is Chocolate Made? Chocolat Naive – Chocolate Making Perfect Daily Grind – Cacao Fermentation Banyan Tree Chocolate – Fun Facts Chocolate Class – Cocoa Production and Trade Hotel Chocolat – Cocoa Beans and Tree Guide ICE – How Cacao Becomes Chocolate NCBI – Cocoa and Chocolate Research

13 What are the Dead Sea Scrolls?

Oxford University Press – Significance of the Dead Sea Scrolls History.com – 6 Things About the Dead Sea Scrolls Smithsonian – Who Wrote the Dead Sea Scrolls? Wikipedia – Dead Sea Scrolls Israel Museum – Dead Sea Scrolls Fast Company – Preservation of Ancient Scrolls Ars Technica – Salt Coating Preserves Scrolls

14 What is the difference between a moth and a butterfly?

Meadowia – Caterpillars and Cocoons Birds & Blooms – Moth vs. Butterfly Butterfly Conservation – Life Cycle English Online – Butterflies and Moths Mom.com – Butterfly Antennae Smithsonian – Moths Smithsonian – Butterflies Library of Congress – Butterfly vs. Moth Australian Museum – Differences Between Butterflies and Moths

15 How do spiders make webs?

WoodyPet – Can Spiders Run Out of Silk? HowStuffWorks – How Spiders Make Webs The Spider Blog – How Spiders Make Webs Natural History Museum – Spider Webs Smithsonian – How Do Spiders Make Webs? Assured Environments – Choosing Web Locations Hamilton Caster – Strength of Spider Silk Wikipedia – Spider Silk Wikipedia – Spider Web

16 Why is carbon-based life common?

Wondrium Daily – Is Silicon-Based Life Possible? FutureLearn – Carbon as the Basis of Life LibreTexts – Carbon: The Chemical Basis for Life Wikipedia – Abundance of Chemical Elements InfoPlease – Organic Chemistry Quora – Why Can’t Silicon Replace Carbon? LibreTexts – Violations of the Octet Rule

17 When did people start wearing wedding rings?

Rustic & Main – History of Wedding Rings Clean Origin – History of Wedding Rings GIA – Origin of Wedding Rings Wikipedia – Wedding Ring Cape Town Diamond Museum – History of Wedding Rings BBC – History of the Wedding Ring Wedding Frontier – Men and Wedding Rings Bloedstone – Men’s Wedding and Engagement Rings

18 What makes things sticky?

ScienceDirect – Polyvinyl Acetate Saws on Skates – What is PVA Glue? Wikipedia – Wood Glue Cold Spring Harbor – Adhesion in Medicine ScienceABC – Why Sugar is Sticky Wikipedia – Masking Tape ACS – Celebrating Chemistry: Adhesives Byju’s – Van der Waals Forces The Naked Scientists – What Makes Things Sticky? Permabond – How Do Adhesives Work? Scientific American – Physics of Stickiness IPG Blog – Masking Tape Basics MATCO – What Makes Tape Stick? Science Notes – Why Sugar is Sticky

19 How does an iron remove wrinkles from clothes?

Starlet Cleaning – History of Ironing UF News – Lice DNA and Early Clothing BBC Bitesize – How Ironing Works The Spec – Science of Wrinkled Clothes All Ironed Out – How Steam Removes Creases American Scientist – Chemistry of Ironing Wikipedia – Ironing Education.com – Wrinkle Removal Experiment Ecuafina – Removing Wrinkles from Wool Sewport – Polyester Fabric Proper Cloth – Formaldehyde in Clothing

20 How quickly do bones biodegrade?

NPR – Determining the Age of Bones Smithsonian – Inside Look at Skeletons ScienceABC – Why Don’t Bones Decay Quickly? Business Insider – Body Decomposition Timeline PubMed – Bone Biodegradation Study Wikipedia – Bone Wikipedia – Bone Marrow Better Health – Bones International Osteoporosis Foundation – Bone Biology LiveScience – How Long Bodies Take to Decompose

21 Why are deserts cold at night?

EarthSky – How Did Desert Sand Form? LabXchange – Heat and Energy in Deserts LiveScience – Why Deserts Get Cold at Night LiveScience – Why Are Deserts Dry? Temperature Master – Does Sand Hold Heat? Earth Eclipse – Does Sand Absorb Water?

22 How does a 3D printer work?

LinkedIn – Factors Affecting 3D Printing Speed Hubs – What is FDM 3D Printing? Market Business News – Potential of 3D Printing ThomasNet – Digital Light Processing (DLP) Hubs – What is SLA 3D Printing? Wikipedia – Stereolithography 3D Systems – Selective Laser Sintering Wikipedia – Selective Laser Sintering CDW – How Does a 3D Printer Work? Independent – What is 3D Printing? BuiltIn – 3D Printing Overview

23 When did cave paintings first appear?

History.com – Prehistoric Cave Paintings Wikipedia – Cave Painting Smithsonian – Oldest Cave Paintings IEP – Higher Order Theories of Consciousness Wikipedia – Prehistoric Art Springer – Origins of Prehistoric Art Frontiers – Neuroscience of Cave Art

24 How much wind does a wind turbine need?

PBS – Wind Speeds for Turbines Renewables First – Windpower Learning Centre Alternative Energy Tutorials – Wind Speed Wikipedia – Wind Turbine National Grid – How Wind Turbines Work Electric Generators Direct – How Generators Work Takoma Battery – Wind Turbine Batteries Composites World – Wind Turbine Blades Good Energy – Wind Turbine Basics EIA – Wind Energy FAQ WiseVoter – Renewable Energy by Country

25 Why is 0 longitude in London?

Royal Museums Greenwich – What is the Prime Meridian? National Geographic – Prime Meridian Wikipedia – Longitude Wikipedia – Prime Meridian (Greenwich) Caliper – What is Longitude? World Atlas – Countries on the Prime Meridian QMUL – Meridian Line as Shared Reference VCU – History of Longitude Get Direction – Latitude and Longitude Tool Maps of World – Latitude and Longitude Map Marine Insight – What is a Sextant? Jagran Josh – Spot the Difference Puzzle Scientific American – Google Maps and Tectonic Plates Royal Museums Greenwich – Prime Meridian

26 Why do stick insects look like plants?

Royal Society – Stick Insects and Camouflage JSTOR Daily – The Incredible Edible Phasmid Egg Wikipedia – Phasmatodea (Stick Insects) The Conversation – Stick Insects Mimic Plants Keeping Insects – Stick Insect Species EurekAlert – Stick Insects and Seed Dispersal

27 Why does blood show up under UV light?

LiveScience – What is Ultraviolet Light? Science World – Black Light Basics Physics Forums – Finding Blood with UV Light Wikipedia – Luminol Northwestern – What Makes EM Radiation Florida Atlantic University – Radiation from the Sun Wonderopolis – Why Things Glow Under Black Light Advanced NDT – UV Light in Forensics Horiba – Detecting Body Fluids with Light Glo Germ – Blood Detection PDF Chemistry World – Blood Detection

28 What will happen at the end of the universe?

NASA – Age of the Universe Wikipedia – Age of the Universe Open Access Government – Universe Age Research Wikipedia – Big Crunch New Atlas – Possible Ends of the Universe Astronomy.com – Big Crunch vs. Big Freeze Space.com – Universe Ending Theories Big Think – Universe Expansion Debate Wikipedia – Big Rip NASA – What is Dark Energy? Big Think – How the Big Rip Could End the Universe American Scientist – Tearing Apart the Universe

29 Why is the Grand Canyon so deep?

Reddit AskScience – Colorado River and the Canyon Wikipedia – Grand Canyon Wikipedia – Colorado Plateau Knowable Magazine – Understanding the Grand Canyon NPS – Grand Canyon Geology Earth Science StackExchange – Grand Canyon and the Ocean Grand Canyon History – Colorado River Wikipedia – Colorado River

30 How was the meter (metre) defined?

National Geographic – How the Meter Was Defined Wikipedia – Metre History.com – Who Invented the Metric System Metric Metal – History of the Metric System Atlas Obscura – Standard Metre in Paris Herong Yang – Meter Based on Pendulum Brainly – How Was the Meter Defined? The Guardian – Redefining the Metre

31 Are Inner and Outer Mongolia separate countries?

Koryo Group – A Tale of Two Mongolias Young Pioneer Tours – Inner vs. Outer Mongolia Wikipedia – Mongolia Wikipedia – Mongol Empire Amicus Mongolia – Inner vs. Outer Mongolia

32 How do facial expressions work?

Amboy Ortho – Muscles Used in Smiling eLife – Facial Expression Mechanisms University of Mustansiriyah – Facial Muscles Lecture Cleveland Clinic – Facial Muscles Wikipedia – Facial Muscles TeachMeAnatomy – Muscles of Facial Expression Kenhub – Facial Muscles Ohio State University – Brain and Facial Expression Recognition Wikipedia – Amygdala NCBI – Brain and Emotion Processing Frontiers – Neuroscience of Facial Expressions Frontiers – Psychology of Facial Expressions

33 Why is Broadway so long?

The Travel – History of Broadway Anthropology in Practice – Wickquasgeck Trail Smithsonian – Native New Yorkers and Broadway Broadway Linear Park – History of Broadway Explanders – Longest Streets in the World Thirteen – Unknown Story of Broadway Wikipedia – Lenape People Wikipedia – Manhattan Wikipedia – Wappinger Wikipedia – Wecquaesgeek Wikipedia – Broadway (Manhattan)

34 Why were the Terracotta Warriors buried?

Smithsonian – Newly Excavated Terracotta Warriors Wikipedia – Terracotta Army Wikipedia – Qin Shi Huang Wikipedia – Mausoleum of the First Qin Emperor National Geographic – Emperor Qin Discover Magazine – Underground Army of Terracotta Warriors China Highlights – Why Were They Built? History.com – Qin Dynasty China Highlights – Terracotta Army Overview Wikipedia – Mausoleum of the First Qin Emperor Taiwan Panorama – Terracotta Army Article

35 Is Earth an open or closed system?

SWSC Journal – Earth as an Open/Closed System University of Vermont – Earth Closed System PDF Lambda Geeks – Is Earth a Closed System? Chiang Mai University – Earth as a Planet OERu – Earth Open and Closed Systems NASA My NASA Data – Systems Thinking ESA – Earth’s Leaking Atmosphere Phys.org – Sun and Earth’s Energy Balance NASA – Earth’s Energy Balance PDF Astronomy.com – Is Earth Gaining or Losing Mass? Science Focus – Is the Weight of the Earth Changing? LiveScience – Earth’s Magnetic Field

36 Are ants and termites the same thing?

Wikipedia – Termite The Spruce – Difference Between Ants and Termites Mongabay India – Secrets of Termite Mounds Rentokil – Ant Nest or Termite Tube? Australian Museum – Ants vs Termites Wikipedia – Ant Pest Samurai – Ant Size Comparison HowStuffWorks – Termites vs Ants Thornybush – Ants vs Termites

37 Why do ducks float?

Science World – Floaters and Sinkers HowStuffWorks – Why Ducks Float Mom.com – Why Ducks Float Explain That Stuff – How Ships Float I Learned This Today – Why Ships Float Harrison Math Classroom – Buoyancy Wiley – Ducks and Buoyancy Ducks.org – Masters of Air and Water

38 When did archaeology start?

Environmental Science – What is Archaeology? Wikipedia – History of Archaeology HowStuffWorks – Archaeology Overview ThoughtCo – The First Archaeologists World History Encyclopedia – Tomb Robbing in Ancient Egypt Etymonline – Origin of the Word Archaeology

39 What causes a stroke?

CDC – About Stroke Mayo Clinic – Stroke Symptoms and Causes NHS – Causes of Stroke NIH – Stroke Causes University of Rochester – Brain’s Energy Supply University of Washington – Blood Vessels and Stroke PNAS – Stroke Research Livestrong – Glucose and Brain Energy TeachMeAnatomy – Arterial Supply of the Brain Wikipedia – Circle of Willis Medical News Today – Circle of Willis Medical News Today – Stroke Definition Hopkins Medicine – Atherosclerosis NIH – Stroke Treatment

40 How does Ransomware work?

Wikipedia – Ransomware Check Point – What is Ransomware? Unitrends – Ransomware Education Digital Guardian – History of Ransomware Attacks DataProt – Ransomware Statistics NSFocus – Paradise Ransomware Source Code HelpRansomware – Decryption Keys PreVeil – Public and Private Key Encryption TechTarget – Public Key Definition Quora – Cracking 256-Bit Encryption Schneier – Quantum Computing and Encryption

41 Why is sea level where it is?

World of Molecules – Solids, Liquids, and Gases VisionLearning – Properties of Liquids Physics StackExchange – Surfaces of Liquids and Gravity National Geographic – Sea Level Wikipedia – Sea Level NASA – Understanding Sea Level Reddit AskScience – Water in Plasma State NASA Climate – Sea Level 101

42 What are food additives?

Science Museum – Food Chemical History Wikipedia – Food Additive WHO – Food Additives Fact Sheet Better Health – Food Additives Valley Food Storage – History of Food Storage Healthy Children – Food Additives and Kids IFIS – Food Additives: Science vs Perception Food-Info – E234 Nisin

43 What is the difference between slugs and snails?

Molluscs.at – Gastropod Morphology Red Butte Garden – Slugs vs Snails A-Z Animals – Slug vs Snail Differences Diffen – Slug vs Snail Epic Gardening – Snail vs Slug Oregon State – Slug Identification Etymonline – Snail Etymonline – Slug Discover Wildlife – How Slugs and Snails Move Discover Wildlife – What is Snail Slime? Hypertextbook – Snail Facts A-Z Animals – Snail Eyes HowStuffWorks – Do Snails Get Shells?

44 Where is the Land of Punt?

SAGE Journals – Land of Punt World History Encyclopedia – Punt That History Nerd – Mythical Land of Punt Think Africa – Land of Punt African History Extra – Demystifying the Land of Punt Wikipedia – Ancient Egypt PBS Nova – Egypt and the Land of Punt Tour Egypt – Punt Wikipedia – Land of Punt Wikipedia – Gash Group

45 Why do we sing Auld Lang Syne at New Years?

Glasgow World – Auld Lang Syne History and Meaning Wikipedia – Auld Lang Syne Proofed – Hogmanay and Auld Lang Syne Time – Auld Lang Syne at New Year’s Eve Economic Times – Why is Auld Lang Syne Sung? The Argus – Singing Auld Lang Syne Sandpoint Reader – Origins of Auld Lang Syne The Morgan Library – Auld Lang Syne (8) The Morgan Library – Auld Lang Syne (1) Michigan Radio – Another Round of Auld Lang Syne Independent – Robert Burns’ Lyrics The Morgan Library – Auld Lang Syne (10) The Morgan Library – Auld Lang Syne (4) Visit Scotland – Hogmanay and Auld Lang Syne Mid-Continent Library – Wee Bit of Scotland Wikipedia – Industrial Revolution in Scotland

46 Why do people pass out from pain?

Better Health – Orthostatic Hypotension NINDS – Orthostatic Hypotension Mayo Clinic – Symptoms and Causes Houston Methodist – Why We Get Dizzy Standing Up Columbia – Fainting and Pain Tolerance Better Health – Fainting Oxford – Vasovagal Syncope Study Wikipedia – Syncope (Medicine) Etymonline – Syncope Byju’s – Blood Pumped per Heartbeat HealthPartners – What Happens When You Faint Cleveland Clinic – Fainting Mayo Clinic – Vasovagal Syncope The Conversation – Fight, Flight or Faint PhysioPedia – Vagus Nerve Cleveland Clinic – Vagus Nerve

47 How many Egyptian dynasties were there?

Wikipedia – Manetho Wikipedia – List of Roman Dynasties Wikipedia – Roman Pharaoh Study.com – Upper and Lower Egypt Wikipedia – Dynasties of Ancient Egypt Discovering Egypt – Kings and Queens Discovering Egypt – Old Kingdom Dynasties Discovering Egypt – Middle Kingdom Dynasties Discovering Egypt – New Kingdom Dynasties Discovering Egypt – Late Period Dynasties Wikipedia – Egyptian Language Bibliotheca Alexandrina – Learn Hieroglyphs

48 When did silent movies end?

Wikipedia – Sound Film Video Librarian – How Talkies Changed Acting Wikipedia – Silent Film Kodak Digitizing – When Silent Films Ended Wikipedia – The Jazz Singer NY Times – Silent to Sound Films Not Coming – Silence After Sound Wikipedia – The Poor Millionaire Art & Object – Oldest Photograph

49 Are ants smart?

Heart SPM – Farmer Ants Herding Aphids Time – Ant Intelligence University of Bristol – Ant Problem-Solving Mind Matters – Leafcutter Ants as Farmers Meadowia – Do Ants Have Brains? Smore Science – Do Ants Have Brains? ScienceDirect – Ant Intelligence Review Scientific American – Rethinking Ant Intelligence KiwiCare – How Smart Are Ants? Science in Poland – Ant Brains

50 Why did some dinosaurs have such long necks?

Washington Post – Why Dinosaurs Had Long Necks LiveScience – How Dinosaurs Grew Long Necks NCBI – Dinosaur Neck Vertebrae Study CNN – Sauropods’ Long Necks Wikipedia – Eusauropoda Wikipedia – Sauropoda Wikipedia – Barosaurus Wikipedia – Diplodocus New Atlas – Dinosaur with 50-ft Neck LiveScience – Diplodocus University of Washington – Bone Evidence of Dino-Bird Link DK Find Out – Inside Diplodocus Everything Dinosaur – Giant Trees of the Dino Age

51 What are moles, freckles, and birthmarks?

Etymonline – Origin of the word “mole” Houston Methodist – When to worry about a mole Cleveland Clinic – Moles overview MSD Manuals – Overview of skin pigment Healthline – Benefits of melanin Wikipedia – Melanocyte Mayo Clinic – Moles: symptoms & causes WebMD – Moles, freckles, and skin tags Cleveland Clinic – Freckles explained KidsHealth – Birthmarks (parent guide) Riley Children’s – Pigmented birthmarks URMC – Vascular birthmarks Wikipedia – Port-wine stain KidsHealth – Port-wine stains

52 Why did the USSR collapse?

TheCollector – Fall of the Soviet Union U.S. State Dept – Collapse of the Soviet Union Britannica – Why the Soviet Union collapsed Brookings – Gorbachev’s role Wikipedia – Dissolution of the USSR Wikipedia – Mikhail Gorbachev Wikipedia – Soviet Union overview National Interest – Could the USSR have survived? Wikipedia – USSR foreign trade IAEA – Chernobyl FAQs Ohio State Origins – Chernobyl context NATO Association – Revisiting Chernobyl FEE – Why Perestroika failed The Conversation – Glasnost’s legacy

53 What is the Fermi paradox?

LiveScience – The Fermi paradox explained Wikipedia – Fermi paradox Wikipedia – Enrico Fermi SETI – Understanding the paradox Royal Society – Statistical takes on the paradox Scientific American – It’s not really a paradox The Conversation – How many stars are there?

54 Who invented the slide rule?

Oughtred Society – History of the slide rule University of Utah – Slide rule primer Wikipedia – Calculator (background) MAA – Napier introduces logarithms Smithsonian – Slide rules collection Etymonline – Origin of “cursor” Math Is Fun – Logarithms explained Plus Maths – Dynamic logarithms National Museums Scotland – Napier’s Bones SciHi – John Napier & logarithms Wikipedia – William Oughtred Wikipedia – John Napier Wikipedia – Slide rule New Mexico Tech – Slide rule handout (PDF)

55 How does insulation in the home work?

Power to Switch – Where the heat goes U.S. DOE – Insulation basics Eco Home Essentials – How insulation works Wikipedia – Second law of thermodynamics Building Materials – Insulation explained Everguard – How insulation works Kingspan – U‑values, R‑values & lambda EcoStar – Insulation R‑value guide

56 Why do tattoos stay in the skin forever?

Dr. Doppelt – What happens under your skin when you get a tattoo British Society for Immunology – Macrophages explained ZME Science – Why tattoos are permanent YouTube – Science of tattoos Business Insider – Why tattoos stay in your skin NBC News – Why tattoos last forever Journal of Experimental Medicine – Macrophage dynamics and tattoos Cleveland Clinic – How skin works Wikipedia – Tattoo machine LabRoots – Tattoo removal strategies Osmosis – Macrophages overview PubMed – Research on tattoo pigments Dermatology Atlanta – Tattoo removal challenges

57 How does ceramic armor work?

AR500 Armor – What happens when a bullet hits ceramic armor Apex Armor Solutions – Do ceramic plates expire? GlobalSpec – Uses of ceramics NASA – Space shuttle ceramic tiles (PDF) Hot Clay – How ceramics are fired University of Washington – Intro to ceramics Wikipedia – Ceramic Ceramic Aspiration – Durability of ceramics Wikipedia – Ceramic armor Spartan Armor Systems – How ceramic body armor works YouTube – Testing ceramic armor AZoM – Ceramic armor technology AZoM – Advances in ceramic armor

58 What animals and insects are pollinators?

Australian Museum – What is pollination? USDA – Who are the pollinators? Buzz About Bees – Wind pollination Seeds.ca – Wind pollination practices Pollinator Partnership – About pollinators Toppr – Pollination process Lumen Learning – Self vs. cross-pollination US Fish & Wildlife Service – Pollination heroes Audubon – Birds, bees & global food supply USDA – Bats as pollinators USDA – Beetles as pollinators Penn State Extension – Flies as pollinators National Park Service – Chocolate midge pollinator

59 Why was the Manhattan Project called the Manhattan Project?

Nuclear Secrecy – Origins of the Manhattan Project name Wikipedia – Klaus Fuchs (atomic spy) US Army Corps of Engineers – Manhattan Engineer District OSTI – Manhattan Project history (1945–46) Wikipedia – Einstein–Szilard letter US Dept of Energy – Background on the Manhattan Project OSTI – Key events in the Manhattan Project OSTI – Discovery of nuclear fission USHistory.org – Manhattan Project summary

60 What is the Streisand Effect?

Wikipedia – Streisand Effect California Coastal Records Project – The original photo controversy California Coastline – The photo Barbra Streisand tried to suppress BBC – The Streisand Effect in action TechDirt – 20 years since the Streisand lawsuit Reporters Committee – Court throws out Streisand’s lawsuit TopTenz – 10 examples of the Streisand Effect

61 Why are bees transported across countries by truck?

NPR – Bees trucked across the U.S. for California’s almond harvest FreightWaves – Life of a honeybee trucker USDA – Economic report on honeybee pollination (PDF) Wikipedia – Almond cultivation in California Entomology Today – Transportation stress on honey bees Museum of the Earth – The role of bees in pollination USGS – Native bee species in the U.S. Gardening Know How – How almond trees are pollinated ICP – California almond pollination factsheet (PDF) The Guardian – When is a nut not a nut? USA Today – Where almonds come from The Guardian – Bee deaths linked to almond pollination

62 Why are some beaches rocky and some sandy?

Reddit AskScience – Why some beaches have sand and others pebbles Woods Hole Oceanographic Institution – How beach sand is created Quora – Why some European beaches have pebbles Beaches of Australia – Rocky vs sandy beaches National Geographic – What is a beach? How It Works – Why some beaches are sandy and others rocky NASA Earth Observatory – Sandy beaches worldwide Views of the World – Mapping the world’s sandy beaches Wonderopolis – Where does beach sand come from? NOAA – Facts about beach sand

63 Why can fish swim so fast?

MIT Technology Review – How fish swim so fast Jaljeev – Fish that cannot swim A-Z Animals – The fastest fish in the ocean Wonderopolis – Who is the fastest swimmer? Maritime Page – Comparing fish speed with submarines JSTOR Daily – What makes fish swim fast

64 How do steroids work?

Wikipedia – Catabolism (breaking down molecules) Healthline – Catabolism vs anabolism MyMed – Science behind anabolic steroids Wikipedia – Steroid Outlook India – Types of steroids MedlinePlus – Steroids explained Versus Arthritis – Steroids as medicine Cleveland Clinic – Anabolic steroids Medical News Today – Exercise vs steroids

65 Why do some countries drive on the left?

Google Books – Historical reasons for left-hand driving Skeptics StackExchange – Did Napoleon influence right-side driving? Reader’s Digest – Why countries drive on different sides UK Car Discount – Why UK drivers keep left Wikipedia – Left- and right-hand traffic History.com – Why some countries drive on the left World Standards – Countries that drive on the left LinkedIn – Why Japan drives on the left Jerry.com – Why countries drive left

66 What causes a heat wave?

Science News – Extreme summer heat waves and the jet stream New York Times – What causes a heat wave? Wikipedia – Heat wave ClimateCheck – What is a heat dome? SciJinks (NOAA) – The jet stream explained Wikipedia – Jet stream Physics StackExchange – Why gases heat up when compressed

67 How thick is tank armor?

HowStuffWorks – M1 Abrams tank and its armor Armored Warfare – Common myths about tanks OS Gamers – Which tank has the thickest armor? Britannica – Tank armor Wikipedia – Challenger 2 tank Wikipedia – Main battle tank Wikipedia – Chobham armor Wikipedia – Vehicle armor APlusPhysics – The physics of tank armor Popular Mechanics – Tank armor explained YouTube – How tank armor works Tank Historia – Why tanks use angled armor

68 Why are electromagnets stronger than permanent magnets?

MagnetSource – Permanent magnets vs electromagnets Maurer Magnetic – Magnetic strength and units Sciencing – How strong are standard magnets? Apex Magnets – Understanding N ratings for magnets K&J Magnetics – Magnet grades Wikipedia – Neodymium magnet Sciencing – Electromagnets vs temporary magnets Stanford Magnets – How to make magnets stronger Magnum Magnetics – Measuring magnet strength Queen Elizabeth Prize – The world’s strongest permanent magnet Adams Magnetic – Neodymium magnets explained IEEE Spectrum – Record-breaking magnetic field New Atlas – Strongest steady magnetic field

69 Are symbiotic relationships always beneficial to both parties?

National Geographic – Symbiosis explained Etymonline – Origin of the word “symbiosis” Wikipedia – Symbiosis ThoughtCo – Commensalism defined and examples A-Z Animals – What sea anemones eat Australian Museum – Why anemonefish don’t get stung AskNature – Mucus coat protects fish from stings BYJU’s – Examples of commensalism NECSI – Parasitic relationships

70 Why do British people say football and Americans say soccer?

Deseret News – Why Americans call football “soccer” Smithsonian – When did we start calling it soccer? Britannica – Why some call football “soccer” Football History – Origins of football Business Insider – Why Americans say soccer Wikipedia – Medieval football Spartacus Educational – Public schools and football World Rugby – History of rugby and football Pro Football Hall of Fame – Timeline of professional football

71 Why aren’t there flying boats anymore?

Mentour Pilot – Where did the flying boats go? Simple Flying – Why flying boats lost popularity Aviation StackExchange – Why were flying boats phased out? Century of Flight – History of flying boats Wikipedia – Flying boat Quora – Difference between flying boats and seaplanes

72 What are rare earth metals?

Science History Institute – History and future of rare earth elements American Geosciences – Why rare earth elements are important Lynas Rare Earths – What are rare earths? Geology.com – Rare earth elements explained Union of Concerned Scientists – EV batteries and rare earths Escatec – Rare earths in electronics manufacturing Versae – The most important metals in electronics CNET – The metals inside your iPhone Lynas Rare Earths – Mining rare earths Ptable – Rare earths on the periodic table

73 What is a nerve?

Scholarpedia – Nervous system overview Cleveland Clinic – What are nerves? Wikipedia – Nerve Wikipedia – Neuron Wikipedia – Axon Wikipedia – Dendrite PBS – Jellyfish without brains Queensland Brain Institute – Axons as cables Khan Academy – Neuron structure and function

74 Why does a boomerang come back?

Street Science – Why boomerangs come back Wikipedia – Precession and torque Futurism – Science of boomerangs Australian Museum – Why a boomerang flies Throwsticks – History and science of boomerangs Wikipedia – Boomerang

75 How does a helicopter with two rotors work?

Wikipedia – Tandem rotor aircraft Wikipedia – Boeing CH-47 Chinook RAF Museum – The Boeing Chinook FairLifts – Top heavy-lift helicopters Wikipedia – Mil Mi-26 FAA – Helicopter Flying Handbook Aviation StackExchange – Helicopter rotor failures Reddit AskEngineers – Chinook rotor mechanics

76 Do all liquids expand when they freeze?

Science Facts – Why water expands when it freezes IAPWS – FAQ on freezing water BCCampus – Water expansion upon freezing Physics StackExchange – Atoms and heat energy Chemistry StackExchange – Does water expand more than other substances? USGS – Polar bonds and water cohesion

77 Why is mercury poisonous?

University of Washington – Why mercury is poisonous ATSDR – Mercury toxzine WHO – Mercury and health Cleveland Clinic – Mercury poisoning Wikipedia – Mercury poisoning Wikipedia – Mercury (element) CDC – Mercury fact sheet Vermont DEC – Mercury information Thermo Fisher – Heavy metals infographic

78 Is a starfish a fish?

Wikipedia – Echinoderm Wikipedia – Radial symmetry Etymonline – Starfish word origin Coastal Review – That which we call a starfish Wikipedia – Starfish Beachcombing Magazine – The starfish is not a fish American Oceans – Are starfish fish? Shape of Life – Radically radial sea star Animals Worlds – Characteristics of fish American Oceans – Starfish facts Bubbly Diver – How starfish breathe

79 Why does iron rust?

ThoughtCo – How rust works Byju’s – Rusting of iron and prevention Monroe Engineering – Why iron rusts ZRC Worldwide – What causes rust I Learned This Today – Why is Mars red? Sciencing – Salt water and rust HowStuffWorks – Why does metal rust? Corrosion Doctors – Rust chemistry Wondrium Daily – Oxidation and reduction reactions Chemistry StackExchange – Why rust needs water

80 Why do many Americans drink coffee and many British people drink tea?

9 Dragons Tea – History of tea in America Golden Moon Tea – Why Americans drink coffee not tea Teabloom – Why coffee is more popular in America Wikipedia – Tea in the United Kingdom Folger – Coffee, chocolate, and tea in England Historic Cornwall – History of coffee in Britain History.com – The Tea Act

81 Why do we sneeze?

Library of Congress – Why pepper makes you sneeze Healthline – Why do we sneeze? Wikipedia – Sneeze Wikipedia – Photic sneeze reflex Wikipedia – Snuff (tobacco) Garden State Treatment Center – Why people snort drugs

82 Why are bridges designed to move?

BuilderSpace – How bridges expand and contract Popular Mechanics – How and why bridges move PhysLink – Bridges and thermal expansion Solar Schools – Thermal energy explained Daily Bruin – Heat and thermal expansion Designing Buildings – Thermal expansion Network Rail – Buckled rail and summer heat Wikipedia – Bridge

83 What is the pH scale?

Wikipedia – pH Wikipedia – Universal indicator USGS – pH scale diagram Dean Academy – Acids and alkalis Britannica – pH Pediaa – Difference between acid and alkaline The Oklahoman – Acids and bases in everyday life Dundee Science Centre – Acids and alkalis Northwestern QRG – What is an ion? News Medical – What makes something acidic or alkaline Toppr – Why acids don’t show acidity without water Wikipedia – Alkali Chemistry StackExchange – Why acids are corrosive

84 Why do we have capital letters?

Babbel – History of capital letters University of Adelaide – History of papyrus Wikipedia – Capitalization in English My Modern Met – Uppercase and lowercase letters

85 When was the first department store?

Country Life – Who opened the first department store? Wikipedia – Department store BBC – History of the department store Etymonline – Word origin of magazine Wikipedia – Shopping mall

86 Why do bees abandon a hive?

Science.org – How pesticides harm bees Orkin – Honey bee colonies DenGarden – Why bees leave a hive Wikipedia – Colony collapse disorder A-Z Animals – Bee predators BeeAware – Varroa mites EPA – Colony collapse disorder

87 Is a force field possible?

Northrop Grumman – Force fields as defense Dune Wiki – Fictional shields Wikipedia – Force field technology New Scientist – Force fields to shield astronauts Space.com – Star Trek technology explained MIT PSFC – What is plasma Medium – Creating force fields

88 What is a jungle?

Get Proofed – English words from Sanskrit Etymonline – Word origin of jungle Burbank Kids – Differences between forests and jungles What’s the Diff – Rainforest vs jungle National Geographic – Rainforests Mongabay – Rainforest floor Wikipedia – Jungle The Daily Eco – Jungle ecosystems

89 What is the difference between a frog and a toad?

Treehugger – Difference between frogs and toads Wildlife Preservation Canada – Frog vs toad Woodland Trust – Frog or toad? Reconnect with Nature – Frog vs toad Wikipedia – Frog Wikipedia – Toad Wikipedia – True toad Etymonline – Tadpole Etymonline – Frog Wiktionary – Middle English word tode Brown University – Frog research National Wildlife Federation – Toads Conserve Wildlife NJ – American toad myths

90 How are memories stored?

Frontiers in Psychology – How memories are stored Harvard Gazette – How neurons form memories Queensland Brain Institute – What is a neuron Washington.edu – Action potentials explained NINDS – Life and death of a neuron Smithsonian – How brains make memories USC Dornsife – How memories are formed QBI – Where memories are stored QBI – How memories are formed

91 Do other planets have tectonic plates?

Astronomy.com – Why Earth has active plate tectonics Wikipedia – Earth’s inner core Astronomy.com – Venus and tectonic activity NASA – Magellan mission to Venus EarthSky – Plate tectonics and alien life Wikipedia – Mars EarthSky – Mars volcanic activity Space.com – Olympus Mons on Mars NC State University – Mercury volcanic activity Wikipedia – Mercury (planet) Earth Magazine – When plate tectonics began on Earth

92 How much height does a parachute need?

Skydive Paraclete XP – Base jumping and altitude UK Skydiving – Minimum parachute opening height The Guardian – Minimum parachute height Enjoy Freefall – Parachute altitudes and records Skydive California – When parachutes are deployed Wisconsin Skydiving Center – How parachutes work Technical Textile – Parachute fabric overview Explain That Stuff – How parachutes work Enjoy Freefall – How fast parachutes open BaseJumping.co.uk – Base jumping in unusual locations Mpora – Base jumping records

93 Is there any historical evidence for Jesus?

Big Think – Was Jesus real? History.com – Historical evidence for Jesus The Guardian – Evidence that Jesus lived and died Wikipedia – Historicity of Jesus Wikipedia – Pauline epistles Wikipedia – Gospel of Mark Columbia College – New Testament context BeThinking – Reliability of Mark’s Gospel

94 Why do shells form in different shapes?

Wikipedia – Mollusc shells Scientific American – How seashells are created Biology Dictionary – Seashells Scientific American – How seashells take shape Ask Dr. Universe – How seashells are formed Australian Academy of Science – Sea shells Laura Perdew – Why seashells have different colors

95 How does an octopus’s suction cup work?

OctoNation – Facts about octopus suckers Dictionary.com – Octopuses or octopi? Wired – How octopuses taste through touch Scuba.com – How octopus tentacles work American Oceans – Octopus suction cup facts BBC Science Focus – How octopuses move without bones Discovery – Octopus arms Scientific American – Tiny hairs help suckers stick Oxford Academic – Suction mechanics of octopus suckers

96 How have sea levels changed over time?

PBS – How the ocean formed and changed Wikipedia – Past sea levels Smithsonian Ocean – Sea level rise through time Wikipedia – History of Earth University of Chicago – Land rising above sea 2.4 billion years ago Phys.org – Ancient sea levels and planet Earth New Scientist – History of ice on Earth Astronomy.com – Snowball Earth periods ASM – The Great Oxidation Event Science – Research on ancient sea levels

97 Who was the first king?

National Geographic – King Sargon of Akkad Getty – Mesopotamian kingship HowStuffWorks – The first king Wikipedia – Sumerian King List Wikipedia – Genesis flood narrative Wikipedia – Enmebaragesi Wikipedia – Alulim Wikipedia – History of Mesopotamia World Atlas – The world’s first king History.com – Earliest civilizations and rulers

98 Why does time go forward not backward?

Popular Mechanics – Could time flow in reverse? BBC Future – Why time goes forwards Reddit ELI5 – Physics of time direction EduInput – Examples of entropy Socratic – Entropy in daily life Chemistry Talk – What is entropy? Physics Stack Exchange – Low entropy at the Big Bang Forbes – Entropy of the universe at the Big Bang Medium – Alternative theory of entropy at the Big Bang

99 What is CRISPR?

YourGenome – What is CRISPR-Cas9? Broad Institute – Q&A on CRISPR Cleveland Clinic – DNA, genes, and chromosomes Genome.gov – DNA fact sheet Wikipedia – CRISPR Genes & Health – Genes made easy YourGenome – What is a gene? MedlinePlus – Non-coding DNA NIGMS – Genetics by the numbers

100 When did sailing ships die out?

National Geographic – Aboriginal Australians and seafaring Wikipedia – Sailing ships LEARNZ – A brief history of sailing Wikipedia – Age of Sail Wikipedia – Steamboat National Park Service – End of the Age of Sail The Dear Surprise – End of the Age of Sail Life of Sailing – Sailing history Wikipedia – Rudder

101 What are stalagmites and stalactites?

Live Science – Stalagmites and stalactites explained National Park Service – Speleothems NOAA – Stalactites in the ocean Wikipedia – Stalactite Wikipedia – Stalagmite National Park Service – Cave formations University of Houston – Carbonates and cave features Mammoth Cave – Stalactites and stalagmites Wikipedia – Helictite

102 Why does Australia have so many dangerous animals?

Reddit AskScience – Why Australia has so many deadly animals Britannica – How deadly are Australia’s animals? National Geographic – Crocodilian ranges Australian Geographic – Australia’s most dangerous animals Expedition Australia – Box jellyfish facts Barrier Reef Australia – Jellyfish dangers Wikipedia – Natural history of Australia NSW Environment – Snake facts Wikipedia – Spiders of Australia Australian Museum – Spider facts

103 What is a speakeasy?

USA Today – What is a speakeasy? History.com – Prohibition era Library of Congress – 18th Amendment Wikipedia – Speakeasy Wikipedia – Second Great Awakening Albert.io – The Second Great Awakening

104 What is a sprain?

Cleveland Clinic – Ligaments explained Better Health – Sprains and strains Visible Body – Joints and ligaments Cleveland Clinic – Joints overview NCBI – Sprains review Mayo Clinic – Sprains causes and symptoms Penn Medicine – Sprains treatment MedlinePlus – Sprain diagram

105 How do night vision goggles work?

Vision Source – Animal eyesight comparison Carnegie Museum – Why cat eyes glow Bushnell – How night vision works RIT – Physics of night vision Wristband – Glow-in-the-dark science BoatSafe – Why night vision is green Best Binoculars Reviews – Digital night vision Photometrics – How an image is made

106 How long do virus and bacteria live for?

Khan Academy – What is life? Merriam-Webster – Virus vs. bacteria differences PubMed – Virus and bacteria survival research University of Queensland – Difference between bacteria and viruses Rockefeller University – What are viruses made of? FSU – Anatomy of a bacteria cell News Medical – How viral replication works Microbiology Society – About bacteria McGill OSS – How long can viruses live outside the body? NC State – How long can viruses survive? Science Focus – Lifespan of bacteria Science Daily – Bacteria longevity research

107 Would President Lincoln have survived if he had been shot today?

Wikipedia – John Wilkes Booth Wikipedia – Assassination of Abraham Lincoln The Atlantic – Would Lincoln have survived today? National Park Service – Aftermath of the assassination Spyscape – Secrets of the presidential limo

108 Why was Mesopotamia the cradle of civilization?

World History Encyclopedia – Mesopotamian inventions National Geographic – History of cities Wikipedia – Mesopotamia History.com – Neolithic Revolution History.com – How Mesopotamia became the cradle Khan Academy – Cradle of civilization The Conversation – Climate change and early empires

109 Why do some plants bloom at night?

USDA – Moths as pollinators L’Observateur – Why some plants flower at night Byju’s – Pollination details Weather Network – Night-blooming flowers Morgan Pawprint – Flowers that bloom at night ABC Gardening – Night flowers Ask A Biologist – Moon flowers Wisconsin Pollinators – Color preferences A-Z Animals – Moth sleep behavior Wikipedia – Crassulacean acid metabolism FNP – Plants that release oxygen at night UCL – Plants and nighttime CO2

110 Why are emulsifiers used in processed food?

PCC Group – Emulsifiers in the food industry Food Insight – What are emulsifiers? WebMD – What are emulsifiers? EUFIC – Common emulsifiers Wonderopolis – Why oil and water don’t mix Chemistry Talk – Polar vs. non-polar bonds Khan Academy – Water as a solvent Healthy Food – Emulsifiers: friend or foe? Cablevey – Processed foods and emulsifiers Zoe – What are emulsifiers? Food Navigator – Emulsifiers and gut bacteria

111 What is an algorithm?

Beaver – Everyday life examples of algorithms TechTarget – Definition of algorithm Programiz – Introduction to algorithms Wikipedia – Algorithm GeeksforGeeks – Nature-inspired optimization algorithms MindMatters – Ants and algorithms Etymonline – Origin of the word algorithm Tableau – Algorithms and data insights

112 Could telekinesis be possible?

Reddit AskScience – Is telekinesis possible? University of Washington – Psychology and telekinesis Discover Magazine – Telekinesis and quantum field theory Wikipedia – Telekinesis Physics Forums – Telekinesis discussion Bond University – Brain energy use Study.com – Electromagnetic waves and energy MIT Technology Review – Neuralink and telepathy

113 Why does ice have so little friction?

Testbook – Friction basics Study.com – Types of friction Vox – Why ice is slippery Phys.org – Slipperiness of ice

114 Where did freemasons come from?

Wikipedia – Freemasonry Wikipedia – Guilds Scottish Rite – History of modern Freemasonry Jefferson County Lodge – Masons vs. Freemasons BBC – Freemasons in Scotland Brewminate – History of guilds Great English Churches – Stonemasons’ world

115 What is a codex?

History of Information – The codex Britannica – Codex manuscript Dartmouth – Scrolls and codices Wikipedia – Parchment Wikipedia – Papyrus Wikipedia – Codex Smithsonian – History of books Google Arts & Culture – History of books New World Encyclopedia – Codex British Library – Writing materials and technologies

116 What is the smallest mammal?

Science Focus – Top 10 smallest mammals Wikipedia – Batodonoides vanhouteni Wikipedia – Etruscan shrew Worldbuilding StackExchange – Advantages of small size Wikipedia – Etruscan civilization Ferrebeekeeper – Metabolism and small animals Pediaa – Warm-blooded animals Save My Exams – Surface area to volume ratio ABP Live – Mammals shrinking brains in winter

117 How fast could an electric car go?

Car and Driver – Why EVs are quick HowStuffWorks – Gas vs electric cars Autocar – Fastest electric cars TopSpeed – EVs and speed metrics GreenCars – Future of EV batteries Litsuit – 412 km/h top speed Wallbox – EVs vs gas cars Energy.gov – Combustion engine basics CNN – In-wheel motors in EVs Kia – Torque in cars Politifact – EV weight vs gas cars AFDC – EV batteries

118 Why does the Leaning Tower of Pisa lean?

Geoengineer – Why Pisa leans Wikipedia – Leaning Tower of Pisa History.com – Pisa tower LeaningTowerPisa.com – Facts Groundworks – Skyscraper foundations

119 Is a whale shark a whale or a shark?

NatGeo Kids – Whale sharks WWF – Whale shark facts Wikipedia – Whale shark Save Our Seas – Shark or mammal? Britannica – What is a mammal? Aquarium of the Pacific – How whales nurse Merriam-Webster – Definition of fish PADI – Diving with whale sharks

120 Where and when did language originate?

BMC Biology – Origin of language study Wikipedia – Origin of language Linguistic Society – FAQ on language beginnings NPR – Why humans can talk National Geographic – Human migration out of Africa NYTimes – Genetic evidence for language

121 Does being cold or wet increase your chance of catching a cold?

Cornerstone Naturopathic – Burnout and immune system Mount Sinai – Sleep and immune system Cleveland Clinic – Stress and immunity Vicks – How your body fights colds Critical Care – Cold stress and illness UCLA Health – Nose temperature and immune response Medical News Today – Vesicles CNN – Why winter colds spread Medical News Today – Colds and cold weather Mayo Clinic – Cold and flu infections Horizon Health News – Winter virus spread American Lung Association – Facts about the common cold NIH – Catching a cold when it’s warm Parkview – Can you catch a cold from the cold?

122 Did Shakespeare write the plays attributed to him?

Shakespeare Authorship – How do we know? Wikipedia – Shakespeare authorship question History.com – Shakespeare authorship debate Wikipedia – William Shakespeare British Library – Shakespeare’s life

123 Why do giant redwood trees grow so big?

California Curated – Why redwoods grow so big EDC – The Redwood Story Wikipedia – Giant sequoia CNN – Hyperion tree Famous Redwoods – Hyperion Treehugger – How hardwood trees grow NPS – Fire and redwoods Northern Woodlands – Why trees grow tall

124 Why does it rain in a rainforest?

NASA Earth Observatory – Rainforests Wikipedia – Temperate rainforest Wikipedia – Temperate climate Mongabay Kids – Why it rains in rainforests CID – Plant transpiration National Geographic – Rainforest ecosystems Wikipedia – Tropical rainforest National Geographic – Photosynthesis

125 Did Christopher Columbus really think he had landed in India?

Reddit AskHistorians – Columbus and India Skeptics StackExchange – Columbus belief Smithsonian – Columbus’s confusion Wikipedia – Christopher Columbus Perceptive Travel – Columbus discoveries Wikipedia – Amerigo Vespucci