How many science facts are there?

100, each with a named source and a link to it. Physics, chemistry and biology, explained plainly.

Where do these facts come from?

Mostly primary sources: NASA, the ESA, museums, universities and peer-reviewed papers. A fact is only published here once a source can be linked, and the wording is written fresh rather than copied.

Can I read them in one sitting?

The page lists the newest first and the search box narrows by word. Every fact links onward to a quiz, game or calculator on the same subject, so it works as a browse or as a jumping-off point.

Mondo Knows Facts

100 Science Facts, Each One Checked and Sourced

Physics, chemistry and biology, explained plainly.

100 facts on this shelf, each with a named source and a link onward to something to play or use on the same theme.

100 facts in Science

ScienceLight travels at nearly three hundred million metres per secondIn a vacuum light travels at an exact speed of 299,792,458 metres per secondNIST ScienceSound travels about four times faster in water than in airDenser molecular packing in liquid water transmits mechanical acoustic waves rapidlyNOAA ScienceAbsolute zero is the theoretical lower limit of temperatureAt minus 273 degrees Celsius all classical thermal motion of atoms stops completelyNIST ScienceLightning bolts are hotter than the surface of the SunA single electrical strike can heat surrounding air to thirty thousand degrees CelsiusNOAA ScienceSuperconductors carry electricity with zero energy lossCooled below a critical temperature certain materials conduct electric current perfectlyUS Department of Energy ScienceLight particles possess energy but no rest massPhotons travel at the speed of light because they carry momentum without rest massNIST ScienceClocks run slower in stronger gravitational fieldsGeneral relativity proves that gravity curves spacetime and slows down the passage of timeNIST ScienceOptical fibres trap light using total internal reflectionLight signals bounce inside glass cores without escaping through the outer boundaryEncyclopaedia Britannica ScienceFaster moving fluid creates lower static pressureBernoulli's principle explains how pressure drops when fluid or air velocity increasesNASA Science ScienceQuantum particles exist in multiple states simultaneouslySubatomic systems remain in a superposition of probability states until measuredNobel Prize ScienceEarth magnetic poles flip every few hundred thousand yearsGeomagnetic reversals swap the North and South magnetic poles over geologic timescalesUSGS ScienceWater exists as solid liquid and gas at its triple pointAt zero point zero one degrees Celsius and specific pressure water coexists in three statesNIST ScienceMatter and light display both wave and particle attributesElectrons and photons behave as localised particles or spreading waves based on test setupNobel Prize ScienceBuoyant force equals the weight of displaced fluidArchimedes principle governs why steel ships float despite their heavy total massEncyclopaedia Britannica ScienceEnergy cannot be created or destroyed only transformedThe total energy in an isolated system remains completely constant over timeUS Department of Energy ScienceParticles moving faster than light in water glow bright blueCherenkov radiation acts as an optical sonic boom for high speed charged particlesUS Department of Energy ScienceMatter and antimatter annihilate into pure gamma raysCollisions between particles and antiparticles convert one hundred percent of mass to energyUS Department of Energy ScienceMoving wave sources shift frequency relative to observersThe Doppler effect compresses approaching sound waves and stretches departing onesNOAA ScienceLight bends when transitioning between different transparent materialsRefraction alters the direction of light waves due to changes in propagation speedEncyclopaedia Britannica ScienceSurface tension allows water striders to walk on liquidCohesive hydrogen bonds draw surface water molecules into an elastic skin-like filmUSGS ScienceDiamond and graphite are made of identical carbon atomsVastly different crystal bonding arrangements give carbon contrasting physical traitsUSGS ScienceHelium remains liquid at absolute zero under normal pressureWeak interatomic forces and high quantum zero-point motion prevent helium from freezingNIST ScienceGallium metal melts in the warmth of a human handA low melting point of thirty degrees Celsius liquifies solid gallium metalUS Department of Energy ScienceThe periodic table organizes elements by proton countAtomic number dictates repeating chemical patterns across periods and groupsNobel Prize

All 100 Science facts

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Turn these facts into a quiz: Science trivia questions, with an explanation after every answer.

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Questions people ask

How many science facts are there?: 100, each with a named source and a link to it. Physics, chemistry and biology, explained plainly.
Where do these facts come from?: Mostly primary sources: NASA, the ESA, museums, universities and peer-reviewed papers. A fact is only published here once a source can be linked, and the wording is written fresh rather than copied.
Can I read them in one sitting?: The page lists the newest first and the search box narrows by word. Every fact links onward to a quiz, game or calculator on the same subject, so it works as a browse or as a jumping-off point.