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193 entries

#001Phases & orbitThe Moon is drifting away from Earth at about 3.8 centimetres a year, roughly the rate your fingernails grow.Earth's tidal bulge sits slightly ahead of the Moon because the planet spins faster than the Moon orbits. That…Lunar Laser Ranging, NASA/ILRS

#002Earth & tidesThe tides that push the Moon away are slowing Earth down too. Days are getting longer by about 1.7 milliseconds per century.It sounds like nothing, and over a human life it is. Over deep time it isn't: sediment records suggest a day lasted…Meyers & Malinverno, PNAS (2018)

#003Phases & orbitThe Moon rises about 50 minutes later each night, which is why a waning Moon feels like it's avoiding you.In one day the Moon moves roughly 13° eastward along its orbit, and Earth needs about 50 extra minutes of spin to…U.S. Naval Observatory

#004Phases & orbitThe Moon does rotate, exactly once per orbit. That's why we only ever see one face.Tidal friction over billions of years matched the Moon's spin to its orbit, a state called tidal locking. It isn't…NASA Moon overview

#005Phases & orbitThere is no dark side of the Moon. There's a far side, and at new moon it's the one in full daylight.Every part of the Moon gets two weeks of sunlight and two weeks of night. At new moon the near side faces us in…NASA Moon overview

#006GeologyThe Moon is not white. It reflects about 12% of the light that hits it, which makes it roughly as dark as worn asphalt.It looks brilliant because it's a grey object against a black sky, lit by an unfiltered Sun. Photograph the Moon…NASA Moon facts

#007ObservingA full moon isn't twice as bright as a half moon. It's about ten times brighter.Two things pile up at full. Half the visible disc is lit at first quarter, but it's lit at a slant, so every crater…NASA Moon facts

#008ObservingThe full moon is the worst night of the month to look at the Moon.With the Sun straight overhead in lunar terms, there are no shadows, so craters and mountains flatten into a bright…NASA Moon observing

#009ObservingPoint binoculars at the line between light and dark. That's where the Moon stops being a disc and becomes a landscape.Along the terminator the Sun sits near the lunar horizon, so crater rims cast long shadows and mountain peaks catch…NASA Moon observing

#010Phases & orbitThe Sun is 400 times wider than the Moon and 400 times farther away. That coincidence is the only reason total solar eclipses exist.The two discs appear almost exactly the same size from Earth, so the Moon can cover the Sun's face and leave the…NASA eclipse resources

#011Phases & orbitTotal solar eclipses will run out. In roughly 600 million years the Moon will be too far away to cover the Sun.As the Moon recedes, its apparent size shrinks. Annular eclipses, the 'ring of fire', where the Moon is too small…NASA eclipse resources

#012Phases & orbitThe Moon passes between us and the Sun every month, and almost never causes an eclipse.Its orbit is tilted about 5° from Earth's orbital plane, so at most new moons the shadow misses above or below…NASA eclipse resources

#013Phases & orbitThe Moon takes 27.3 days to orbit Earth but 29.5 days to get back to the same phase.By the time it has completed one lap against the background stars, Earth has moved a month's worth along its own…NASA Moon facts

#014GeologyThe leading theory is that the Moon is a piece of Earth, blasted loose by a collision with a Mars-sized world.About 4.5 billion years ago a body nicknamed Theia struck the young Earth. The debris settled into orbit and…Lunar and Planetary Institute

#015GeologyThe Moon has earthquakes. Some of them ring for over an hour.Apollo seismometers recorded four kinds, including shallow quakes up to about magnitude 5.5. With no water in the…Apollo Passive Seismic Experiment, NSSDC

#016GeologyThe Moon is shrinking. It has lost about 50 metres of circumference as its interior cools, and the surface is wrinkling like old fruit.Lunar Reconnaissance Orbiter found thousands of small cliffs, thrust faults, where the crust has buckled and shoved…Lunar Reconnaissance Orbiter

#017GeologySome craters at the lunar poles are colder than the surface of Pluto. Sunlight has not touched their floors in billions of years.The Moon's axis is nearly upright, so at the poles the Sun never climbs high enough to reach into deep craters…LRO Diviner

#018GeologyThere is water on the Moon, as ice in polar craters, and as molecules scattered across the sunlit surface.Orbiters mapped hydrogen at the poles for years, and in 2009 the LCROSS impactor kicked up a plume containing…NASA Moon overview

#019GeologyLunar noon is about 120°C. Lunar night is about -170°C. The same rock does both, twice a month.There is essentially no atmosphere to move heat around or hold it in, so the surface tracks the Sun directly. A…LRO Diviner

#020MissionsMoondust smells like spent gunpowder. Apollo crews tracked it into the lander and noticed immediately.Nobody has fully explained it. The dust is freshly fractured rock that has never met oxygen or water, so the moment…Apollo crew debriefs, NASA

#021GeologyLunar dust is vicious. With no wind or water to round it off, every grain is still a tiny shard of broken glass and rock.Micrometeorite impacts melt and shatter the surface constantly, producing sharp, statically charged particles…Apollo dust studies, NASA

#022MissionsThe Apollo footprints are still there, and will be for millions of years.No wind, no rain, no plate tectonics. Only micrometeorite bombardment slowly erodes the surface, at something like…NASA history

#023MissionsTwelve people have walked on the Moon. All twelve did it inside a three and a half year window, between 1969 and 1972.Six Apollo landings, two crew each. The last was Apollo 17 in December 1972, and Eugene Cernan was the last to step…NASA Apollo record

#024MissionsApollo brought home 382 kilograms of the Moon, and scientists are still finding new things in it. Some of it was deliberately left sealed for decades.NASA held back pristine samples on the bet that future instruments would beat 1970s ones, and that bet paid off…JSC Lunar Sample Curation

#025MissionsApollo left mirrors on the Moon. Observatories still fire lasers at them, and the round trip is measured to the millimetre.Apollo 11, 14 and 15 deployed corner-cube retroreflectors, joined by two Soviet Lunokhod rovers. Fire a laser…International Laser Ranging Service

#026MissionsHumanity saw the far side of the Moon for the first time in October 1959, in grainy photographs radioed back by Luna 3.For every human being before that year, nearly half of the nearest world was simply unknown. The images were poor…NSSDC Luna 3

#027GeologyThe far side looks like a different moon. It's rugged, cratered, and almost free of the dark plains that make up the 'man in the Moon'.The crust on the far side is substantially thicker, so ancient lava had a much harder time reaching the surface…Lunar and Planetary Institute

#028GeologyThe far side holds one of the largest impact craters in the solar system: the South Pole–Aitken basin, about 2,500 km across and 8 km deep.Whatever hit there punched through most of the crust, which makes the basin floor the best place to sample the…Lunar and Planetary Institute

#029MissionsThe first soft landing on the far side happened in 2019, sixty years after the first photograph of it.China's Chang'e 4 set down in Von Kármán crater inside the South Pole–Aitken basin. Because the far side never…NSSDC mission catalogue

#030MissionsBefore 1966 nobody knew whether a spacecraft would sink into the lunar dust. Luna 9 landed and didn't, which is how we found out.Some respected scientists had argued the surface might be covered in metres of loose powder. The Soviet Luna 9…NSSDC mission catalogue

#031ObservingA 'supermoon' really is bigger, about 14% wider and 30% brighter than a full moon at its farthest. You will almost certainly not notice.The orbit is an ellipse, so the distance swings between roughly 356,500 and 406,700 km. The difference is…NASA Moon facts

#032ObservingThe Moon looks enormous on the horizon and normal overhead. It is the same size in both. The effect is entirely in your head.Photograph it in both positions with the same lens and the discs measure identically, if anything the horizon Moon…NASA Moon facts

#033ObservingOn a thin crescent you can often see the whole disc faintly glowing. That's Earth, lighting the Moon's night.When we see a slim crescent, an astronaut on the Moon would see a nearly full Earth, four times wider than our Moon…NASA Moon observing

#034ObservingThe harvest moon isn't bigger or oranger. It rises unusually early for several nights running, and that's the whole trick.Around the September equinox the Moon's path meets the horizon at a shallow angle, so the usual 50-minute delay…U.S. Naval Observatory

#035ObservingA low Moon looks orange for the same reason a low Sun does: you're looking through a lot more atmosphere.Near the horizon the light path through the air is many times longer than overhead. Air scatters blue light away…NASA Moon observing

#036Strange but trueThe Moon you're looking at is 1.3 seconds old.Light covers the average 384,400 km in about 1.28 seconds. It's the only object in the sky whose delay is short…NASA Moon facts

#037Strange but trueEvery planet in the solar system would fit in the gap between Earth and the Moon, side by side, with room left over.Add up the equatorial diameters of Mercury through Neptune and you get roughly 380,000 km against an average…NASA planetary fact sheets

#038Strange but trueOur Moon is the fifth largest in the solar system, and by far the largest compared to the planet it orbits.Ganymede, Titan, Callisto and Io are all bigger. But those orbit giants. Our Moon is more than a quarter of Earth's…NASA Moon facts

#039GeologySurface gravity is about one sixth of Earth's, which is why Apollo crews gave up walking and started hopping.Normal walking relies on falling forward onto the next foot, and at one sixth g you fall too slowly for it to feel…NASA Apollo surface operations

#040Strange but trueThe Moon has a tail. A stream of sodium atoms trails away from it for hundreds of thousands of kilometres, and around new moon Earth passes through it.Micrometeorite impacts and solar wind knock sodium off the surface, and sunlight pushes it downstream like a very…Boston University imaging science

#041GeologyThe Moon has no global magnetic field today, but its oldest rocks are magnetised, so it used to have one.Apollo samples carry a frozen-in record of a field comparable to Earth's, which means the Moon once had a churning…Apollo sample paleomagnetism, NASA

#042Strange but trueThere are pale swirls painted across the lunar surface that nobody has fully explained.Reiner Gamma is the famous one, a bright, looping shape with no relief at all; it isn't a crater or a hill. Swirls…Lunar Reconnaissance Orbiter

#043GeologyThe bright streaks fanning across the full moon come from one crater. Tycho's rays reach 1,500 km from the impact.Tycho is young, about 108 million years old, which on the Moon counts as recent, so its ejecta hasn't yet been…Lunar Reconnaissance Orbiter

#044Strange but trueThe Moon's dark patches are called seas because early astronomers thought that's what they were. The names stuck anyway.Giovanni Riccioli laid down the naming scheme in 1651: Sea of Tranquility, Ocean of Storms, Sea of Crises. They're…Lunar and Planetary Institute

#045Earth & tidesThe biggest tides of the month arrive at new and full moon, when the Sun and Moon pull in line.The Sun raises tides too, about 46% as strong as the Moon's. When all three bodies line up the effects add, giving…NOAA tides and currents

#046Earth & tidesThere are two tidal bulges, not one. The far side of Earth bulges away from the Moon.Tides come from the difference in the Moon's pull across Earth's width. The near side is pulled harder than the…NOAA tides and currents

#047Earth & tidesThe Moon steadies Earth's tilt. Without it, our axis would likely wander much more, and climate with it.A large moon damps the chaotic tilt wobbles that gravitational nudges from other planets would otherwise produce…Laskar et al., Nature (1993)

#048Earth & tidesThere is no measurable full moon effect on births, crime, or emergency rooms. It has been checked many times.A 1985 meta-analysis pooled dozens of studies and found essentially nothing. The persistent belief is a good…Rotton & Kelly, Psychological Bulletin (1985)

#049Strange but true'Lunatic' comes from the Latin word for moon. 'Month' and 'Monday' come from the Old English one, back when the Moon was the calendar.The Moon was humanity's first reliable clock, a repeating unit longer than a day and shorter than a year, visible…Oxford English Dictionary

#050Phases & orbitMoon phases repeat on the same calendar dates every 19 years, almost exactly. Easter is still calculated from that fact.235 lunar months come to within a couple of hours of 19 solar years, the Metonic cycle, named for the Athenian who…U.S. Naval Observatory

#051Phases & orbitEclipses repeat every 18 years, 11 days and 8 hours. The Babylonians had that worked out before anyone knew what caused one.The saros cycle brings the Moon back to the same phase, the same distance, and the same node all at once, so a very…NASA eclipse resources

#052ObservingDuring a total solar eclipse the Moon's shadow sweeps across the ground faster than a jet, well over 1,600 km/h even where it's slowest.The shadow's speed is the Moon's orbital motion minus the ground's rotation beneath it, so it's slowest near the…NASA eclipse resources

#053ObservingA totally eclipsed Moon turns red because it's lit by every sunrise and sunset on Earth at once.Earth's shadow isn't truly black: our atmosphere bends and filters sunlight into it, stripping out blue. Standing…NASA eclipse resources

#054ObservingLunar eclipses are no more common than solar ones. You will still see far more of them in your life.A solar eclipse paints a shadow track a couple of hundred kilometres wide; you have to be in it. A lunar eclipse is…NASA eclipse resources

#055Strange but trueMoonbows are real. A bright full moon and falling rain will make a rainbow, though your eyes usually see it as white.The physics is identical to a solar rainbow, the light is just about 400,000 times fainter, and at that level your…NASA Moon observing

#056MissionsThere are trees on Earth grown from seeds that went to the Moon and back.Apollo 14's command module pilot Stuart Roosa, a former smokejumper, carried around 500 tree seeds in his personal…NASA history

#057GeologyThe Moon has a core, and part of it is still molten. It is tiny: about a fifth of the Moon's radius, against half for Earth's.Reanalysis of Apollo seismic data in 2011 found a solid inner core and a fluid outer one, with a partly melted…Apollo seismic reanalysis, NASA

#058GeologyThe Moon is covered in a layer of pulverised rock several metres deep, made almost entirely by things hitting it.With no atmosphere to burn up incoming debris, four billion years of impacts have ground the top of the crust into…Lunar and Planetary Institute

#059Phases & orbitTime-lapse a month of moons and the Moon appears to nod, rock and pulse. We call it libration, and it's how we see 59% of the surface.The Moon's spin is steady but its orbital speed isn't, because the orbit is an ellipse, so it runs slightly ahead…NASA Scientific Visualization Studio

#060ObservingThe brightest spot on the Moon is a crater called Aristarchus. It's bright enough that people have mistaken it for activity on the surface.Aristarchus sits on a plateau of unusually reflective material and is geologically fresh, making it stand out…Lunar Reconnaissance Orbiter

#061Strange but trueThe face in the Moon is made of lava flows 3 billion years old. Different cultures see a rabbit, a woman, a toad, or a man carrying sticks.The dark maria are the same shapes for every human being on the planet, the Moon has kept the same face turned…Lunar and Planetary Institute

#062ObservingThe Moon covers about half a degree of sky. Hold a pencil eraser at arm's length and you can hide it completely.Half a degree is roughly a fifth the width of your little finger held out at arm's length. Every photograph in…U.S. Naval Observatory

#063Strange but trueThe Moon is silent. Not quiet. Silent. There's no air to carry a sound from one place to another.Apollo astronauts standing a metre apart could only hear each other by radio. What they could hear was sound…NASA Apollo surface operations

#064Phases & orbitThe Moon never loops back on itself as it travels around the Sun. Its path is nearly a circle with a slight ripple in it, always curving the same way.The Sun pulls on the Moon about twice as hard as Earth does. Draw the Moon's actual track around the Sun and you…NASA Moon overview

#065Strange but trueA blue moon isn't blue and the popular definition is a mistake, a 1946 magazine misreading that everyone liked too much to fix.The older, seasonal meaning is the third full moon in a season that has four. Sky & Telescope garbled it into 'the…Sky & Telescope, 1946 / 1999 correction

#066MissionsIn April 2026 four people flew around the far side of the Moon and came home. It was the first time humans had left low Earth orbit since 1972.Artemis II carried Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen on a ten-day loop out and back…NASA Artemis II

#067MissionsThe farthest any human has ever been from Earth is 406,771 km. The record it broke had been set by accident.Artemis II passed the mark on 6 April 2026, looping around the far side on a free-return path with the Moon near…NASA Artemis II

#068MissionsApollo 11 landed with less than a minute of fuel left by the flight rules, while Armstrong flew past a boulder field looking for somewhere flat.The guidance computer was steering them into a crater strewn with rocks, so Armstrong took semi-manual control and…Apollo 11 mission transcript, NASA

#069MissionsFor eight years the Moon had a working seismic network. It was switched off in 1977 to save about a million dollars a year.Apollo 12, 14, 15 and 16 left seismometers that ran continuously and recorded thousands of events. Funding ended…Apollo Passive Seismic Experiment, NSSDC

#070Strange but trueThe zodiac signs no longer line up with the constellations they're named after. They slipped about a whole sign over two thousand years.Earth's axis wobbles like a spinning top, one full circle every 25,772 years. That is precession. Western astrology…U.S. Naval Observatory

#071Phases & orbitNobody in an observatory calls it a half moon. "First quarter" counts the orbit, not the shape.By the time half the disc is lit, the Moon has covered 90° of its circuit, one quarter of the way from new moon to…U.S. Naval Observatory

#072Strange but trueAround 270 BC, a Greek worked out how far away the Sun is using nothing but a half moon and an angle.When the Moon is exactly half lit, the Sun, Moon and Earth form a right angle at the Moon, so measuring the…Aristarchus, On the Sizes and Distances (c…

#073ObservingFor about four hours before every first quarter, sunlight catches three crater rims at the right angle and spells a letter X on the Moon.The Lunar X sits on the terminator near the craters Blanchinus, La Caille and Purbach: the rims are already in…NASA Moon observing

#074GeologyThere is a 110-kilometre cliff on the Moon that looks drawn with a ruler. It's a black line after first quarter and a white one after last.Rupes Recta, the Straight Wall, is a fault where the crust dropped a couple of hundred metres along an almost…Lunar Reconnaissance Orbiter

#075ObservingThe first quarter moon rises around noon. Roughly half of all the Moon's time above the horizon is spent in a blue sky, and almost nobody looks up.Only the full moon keeps strictly to the night, rising at sunset and setting at sunrise. Every other phase shares…U.S. Naval Observatory

#076ObservingThe line between light and dark on a waxing moon is a sunrise. On a waning moon it's a sunset. You are watching dawn cross another world at cycling pace.The terminator sweeps the lunar equator at about 15 km/h. On the waxing half it is the morning line, uncovering…NASA Moon observing

#077ObservingSerious lunar observers look at the same crater twice a month, because at last quarter the shadows fall the other way.The Sun rises over a feature during the waxing half of the cycle and sets over it during the waning half, lighting…Lunar and Planetary Institute

#078ObservingMajor observatories schedule their whole year around the Moon. The nights near new moon are called dark time, and astronomers fight over them.Telescope committees split the calendar into bright, grey and dark time by lunar phase. Faint galaxies and distant…Observatory time-allocation practice (ESO…

#079ObservingThe most common reason a meteor shower disappoints is not cloud. It's the Moon.A gibbous moon washes out everything but the brightest few meteors. Shower dates are fixed by Earth's orbit while…American Meteor Society

#080Strange but true"Gibbous" means humpbacked. English has no everyday word for the shape, so astronomy borrowed a medical one.From the Latin gibbus, a hump. It described hunched posture in medieval medical writing long before it described…Oxford English Dictionary

#081ObservingA crescent's horns always point directly away from the Sun. It is a compass, and it is how you catch a fake moon in a painting.The lit edge faces the Sun, so the line joining the two tips is square to the Sun's direction, which tells you…NASA Moon observing

#082ObservingCrescent-spotting is a competitive sport. The youngest moon ever caught by naked eye was under sixteen hours old.As the crescent thins, mountains along the limb break it into beads and then swallow it entirely, the Danjon limit…Danjon (1932); observer records, Sky &…

#083Earth & tidesThat faint glow filling in the crescent's dark side is a measurement. Track it for years and it tells you how reflective Earth has become.Earthshine is sunlight bounced off Earth onto the Moon and back to us, so its brightness follows Earth's albedo…Danjon (1928); Big Bear Solar Observatory…

#084ObservingNear the equator the crescent lies on its back like a bowl. In Scotland it stands upright like a C. Nothing has tilted but you.The lit side always points at the Sun; what changes is the angle the Sun's path makes with your horizon. Near the…U.S. Naval Observatory

#085Phases & orbitA new moon is up all day. It rises with the Sun, crosses the sky beside it, and sets with it, invisible the entire way.New moon is not the Moon being away; it is the Moon in the daytime sky, lost in glare a few degrees from the Sun…U.S. Naval Observatory

#086ObservingMost people who notice the Moon in daylight are looking at a waning one, through a windscreen, on the way to work.After full moon the Moon rises later each night and is still well up after sunrise, so the waning gibbous and last…U.S. Naval Observatory

#087GeologyNear first quarter, the Moon seems to grow mountains. Low sunlight casts long shadows across the lunar Apennines, making the range stand out in binoculars. Apollo 15 landed at the range’s edge and explored its foothills.Montes Apenninus runs roughly 600 km along the rim of Mare Imbrium, with peaks rising more than 5 km. Near first…Lunar Reconnaissance Orbiter

#088Phases & orbitNo two lunations are the same length. They run from 29.27 days to 29.83, thirteen hours between the extremes.29.53 days is an average, not a timetable. The orbit is an ellipse and the Earth-Moon pair is itself swinging…Meeus, Astronomical Algorithms, ch. 49

#089ObservingThe fortnight after full moon is when the sky quietly comes back. Every night the Moon arrives later, and every night you can see more.From full to new, moonrise slides from sunset all the way round to sunrise, handing the early evening back to…NASA Moon observing

#090ObservingThe waning crescent is the phase almost nobody has seen, for the simple reason that it only comes out shortly before dawn.It is the mirror image of the young evening crescent everyone knows, hanging in the east before sunrise with the…NASA Moon observing

#091Strange but trueBali switches off — no lights, no traffic, no flights in or out — for twenty-four hours every year, on a day that always falls at new moon.Nyepi, the Balinese day of silence, runs 6am to 6am. Everyone stays indoors, artificial light is restricted…Balinese saka calendar; annual Ngurah Rai…

#092Strange but trueSri Lanka gives a public holiday on every full moon, which is twelve or thirteen days a year decided entirely by the Moon.Poya days mark the full moon in the Buddhist calendar and each one is a national holiday: shops close, alcohol is…Sri Lanka public holiday calendar

#093Earth & tidesA purely lunar year is about eleven days short of a solar one, so Ramadan drifts backwards through the calendar and works its way round every season in about thirty-three years.Twelve lunations come to roughly 354.37 days against the solar year's 365.24. The Islamic calendar keeps the Moon…Umm al-Qura calendar; 12 × 29.530588 days…

#094Phases & orbitThe Moon does not orbit the centre of the Earth. Both bodies swing around a shared balance point about 4,670 kilometres from Earth's middle, which is still 1,700 kilometres underground.The Earth is eighty-one times heavier, so the balance point sits eighty-one times closer to it — deep inside the…NASA Moon facts

#095Phases & orbitDepending on what you measure from, a month is 27.32 days, 29.53 days, 27.55 days, 27.21 days or 27.32 days again — and all five are in use.The sidereal month returns the Moon to the same star; the synodic month returns it to the same phase and is longer…Explanatory Supplement to the Astronomical…

#096Phases & orbitThe points where the Moon rises and sets swing north and south along the horizon over a month, and the width of that swing itself grows and shrinks over 18.6 years.The Moon's orbit is tilted about 5.1 degrees to Earth's path round the Sun, and that tilt slowly rotates, taking…Royal Museums Greenwich; English Heritage…

#097Phases & orbitEclipses cluster into seasons about 173 days apart, which is short of half a year, so they creep backwards through the calendar.An eclipse needs the Moon near one of the two points where its tilted orbit crosses Earth's. Those points drift…NASA eclipse resources

#098Phases & orbitThe saros repeats an eclipse every 18 years, but a third of a day out, so the Earth has turned and the shadow lands a third of the way round the world. Wait three saroses and it comes home.18 years 11 days and 8 hours is the saros; those extra 8 hours are why the same eclipse walks 120 degrees west each…NASA eclipse resources

#099Phases & orbitAlmost every large moon in the solar system orbits over its planet's equator. Ours does not: it stays within about five degrees of Earth's path around the Sun instead.A moon that formed from a disc around its planet inherits the planet's equator, which is what Jupiter's and…Canup & Asphaug, Nature 412, 708 (2001)

#100Phases & orbitThe Moon already keeps one face to us. Given long enough the Earth would do the same back, and a day and a month would both be about 47 of our present days.Tides are slowing the Earth and widening the Moon's orbit, and the process only stops when both rotations match the…Murray & Dermott, Solar System Dynamics (1999)

#101Phases & orbitAgainst the background stars the Moon shifts about half a degree an hour — its own apparent diameter — which is slow enough to be invisible and fast enough to watch.Thirteen degrees a day works out at roughly one Moon-width per hour. Line the edge up with a rooftop or a branch…NASA Moon facts

#102Phases & orbitSunrise to sunrise at a spot on the Moon takes 29.5 Earth days, so any base there has to sit through about 354 hours of continuous night.Because the Moon turns once per orbit, the Sun crawls across its sky at half a degree an hour. Fourteen days of…NASA Moon facts

#103Phases & orbitThe Moon's orbit is an ellipse, and the whole ellipse slowly rotates, taking eight years and ten months to come back round.The Sun's pull tugs hardest on whichever side of the orbit is nearest it, and the result is that the line joining…Clairaut, Theorie de la Lune (1752)

#104Phases & orbitAt 3.8 centimetres a year, the Moon is about two metres further away than it was when the last mirrors were set up on it in 1972.That is the whole measurement, and it is the reason the mirrors matter. Bouncing a laser off them times the round…International Laser Ranging Service

#105Phases & orbitWhen the Moon is near its far point it is too small to cover the Sun, and a total eclipse becomes a ring of fire instead.The Moon's apparent size varies by about 14% between perigee and apogee, and the Sun's by 3% over the year. For…NASA eclipse resources

#106Phases & orbitThe phase is a fact about where the Sun, Earth and Moon are, so it is identical in Tokyo and Lima at the same instant. Only the angle it hangs at changes.What differs from place to place is orientation and timing: a crescent that stands up like a bowl at the equator…Meeus, Astronomical Algorithms, ch. 48

#107Phases & orbitA new moon only eclipses the Sun if it happens within about fifteen degrees of the point where the Moon's orbit crosses Earth's — roughly a day and a bit of travel.Outside that window the Moon passes above or below the Sun and nothing happens, which is most months. The window…NASA eclipse resources

#108Phases & orbitIt covers roughly 3,680 kilometres an hour along its orbit, which works out at almost exactly the muzzle velocity of a rifle bullet — and about an eighth the speed of the space station.Orbital speed falls with distance, and at 384,400 kilometres out the Moon is dawdling compared with something…NASA Moon facts

#109Phases & orbitThe Moon rises about 50 minutes later each night on average, but the real figure runs from about 20 minutes to nearly 80, depending on the season and how far north you are.The delay depends on the angle the Moon's path makes with the horizon, which changes through the year and steepens…U.S. Naval Observatory rise and set data

#110GeologyA hole in the Sea of Tranquillity, about a hundred metres across, was shown in 2024 to open sideways into a cave — the first lunar cave anyone has proved exists.Radar from lunar orbit picked out reflections consistent with a conduit tens of metres long running off the bottom…Carrer et al., Nature Astronomy (2024)

#111GeologyThe lava plains that make the face in the Moon cover about a third of the near side and almost nothing of the far side.The near side is where the crust is thin enough for magma to have reached the surface. Whatever caused that…NASA Lunar Reconnaissance Orbiter

#112GeologyTwo spacecraft flying in formation measured the Moon's gravity precisely enough to weigh its crust, and found the far side carrying roughly twice as much of it.GRAIL flew twin probes in 2012 and tracked the distance between them to a fraction of a micrometre a second. The…Wieczorek et al., Science 339, 671 (2013)

#113GeologyThe bright parts of the Moon are made of a rock that floats. Early on the whole surface was molten, and the light crystals rose to the top and set there.Apollo 11 came back with white anorthosite fragments that had no business being in a basalt plain, and the…Wood et al., Apollo 11 Lunar Science…

#114GeologyThe Moon's centre of mass sits about two kilometres closer to us than its geometric centre, which is part of why it keeps the same face turned our way.The near-side crust is thinner and the dense mare basalts are piled on that side, so the mass is not evenly spread…NASA Lunar Reconnaissance Orbiter

#115GeologySpacecraft circling the Moon in the 1960s kept drifting off course, and the reason turned out to be buried concentrations of mass under the big round seas.They were named mascons, for mass concentrations, and they are dense material that welled up under the impact…Muller & Sjogren, Science 161, 680 (1968)

#116GeologyThe high ground on the Moon is not a mountain range but the raised rim of the largest crater in the solar system, about 10.8 kilometres above the average surface.It sits on the far side, close to the edge of the South Pole-Aitken basin, and nobody standing on it would…Lunar Orbiter Laser Altimeter, NASA LRO

#117GeologyReanalysis in 2023 found a solid ball of iron about 500 kilometres across at the Moon's centre, wrapped in a molten outer core — the same layered arrangement Earth has.The evidence is indirect: decades of laser ranging and orbital tracking, plus the old Apollo seismic records, fed…Briaud et al., Nature 617, 743 (2023)

#118GeologyA telescope flying in a converted 747 detected molecular water in Clavius crater, on ground that gets full daylight and reaches 100°C.Ice in permanently shadowed polar craters had been expected. Water surviving in the open had not. The amounts are…Honniball et al., Nature Astronomy 5, 121…

#119GeologyA few high points near the Moon's south pole are in sunlight more than 80% of the year, because the Moon barely tilts and the Sun barely dips.The Moon's axis leans only 1.5 degrees, so at the poles the Sun grinds around the horizon rather than rising and…Mazarico et al., Icarus 211, 1066 (2011)

#120GeologyScattered patches of rough, blistered ground carry so few craters that they look less than 100 million years old, which is a blink in lunar terms.The Moon was supposed to have finished erupting around a billion years ago. These irregular mare patches — about…Braden et al., Nature Geoscience 7, 787 (2014)

#121GeologySeveral hundred meteorites found on Earth are lunar — knocked off the Moon by impacts and picked up centuries or millennia later, mostly in Antarctica and the Sahara.They are identified by matching their chemistry to the Apollo and Luna samples, which is why the returned material…NASA Lunar Sample Curation

#122GeologyAbout 45% of the mass of lunar soil is oxygen, locked into rock. Getting it out takes a great deal of energy and no water at all.Every silicate mineral up there is built around oxygen atoms, so the raw material for breathing and for rocket…Lunar Sourcebook, Lunar and Planetary…

#123GeologyThere is gas around the Moon — argon, helium, sodium, potassium — but so little of it that the whole atmosphere weighs a few tens of tonnes, about as much as one loaded lorry.At the surface it is around a hundred trillion times thinner than the air at sea level, thin enough that the atoms…Stern, Reviews of Geophysics 37, 453 (1999)

#124GeologySurveyor landers photographed a faint glow along the horizon after sunset, and the leading explanation is that sunlight charges the dust until the grains push each other off the ground.With no air to hold them, charged grains a few micrometres across can hop, and near the terminator the charge…Rennilson & Criswell, The Moon 10, 121 (1974)

#125GeologySmall telescopes pointed at the Moon's night side catch flashes when meteoroids hit — several hundred have been recorded since 2005.With no atmosphere, nothing burns up; a rock the size of a grapefruit arrives at twenty kilometres a second and its…NASA Meteoroid Environment Office, lunar…

#126GeologyHadley Rille is a kilometre and a half wide and three hundred metres deep, and it meanders like a river — but nothing has ever flowed through it except lava.Sinuous rilles are collapsed lava tubes or channels cut by molten rock, and Apollo 15 landed beside this one…Apollo 15 Preliminary Science Report, NASA…

#127GeologyFresh lunar rock is pale grey. Left exposed, the solar wind and micrometeorites darken and redden it over tens of millions of years, so brightness is a rough clock.Tiny impacts melt and vaporise the surface, coating grains in iron-rich glass; the solar wind implants hydrogen…Hapke, J. Geophys. Res. 106, 10039 (2001)

#128GeologyThere is no wind, no rain and no plate tectonics up there, so a four-billion-year history of what has been flying around this part of the solar system is still lying on the surface.Earth has been hit at least as hard and has erased nearly all of it. The Moon has not: the crater record is what…Lunar and Planetary Institute

#129MissionsSomething like 200 tonnes of human-made material sits on the Moon, spread across roughly a hundred sites — landers, rovers, crashed rockets, spent stages and a lot of discarded equipment.Most of it was left on purpose. Every kilogram lifted off the surface cost fuel, so the Apollo crews jettisoned…NASA Space Science Data Coordinated Archive

#130MissionsThe Apollo crews left about ninety-six bags of urine, faeces and vomit on the surface, because mass going up was worth more than dignity.Every bag left behind was a bag's worth of rock that could come home instead. Whether anything in them is still…NASA Apollo mission reports; Apollo Lunar…

#131MissionsAlan Shepard hit two golf balls on the Moon in 1971 and said the second went "miles and miles and miles". Image analysis in 2021 found them: 24 yards and 40.He was swinging one-handed in a pressurised suit that would not let him turn his shoulders, with a club head taped…Andy Saunders / United States Golf…

#132MissionsApollo 12 landed 160 metres from Surveyor 3, which had been sitting there for two and a half years, and the crew walked over and cut pieces off it to bring home.It is the only time anyone has retrieved hardware from another world. A famous claim followed — that living…Analysis of Surveyor 3 Material, NASA SP-284…

#133MissionsLunokhod 1 stopped answering in 1971 and nobody could find its laser reflector again until 2010, when a photograph from orbit showed where the rover had parked.Its twin, Lunokhod 2, had been ranged for decades. The first rover's last position was known only to within a few…Murphy et al., Icarus 211, 1103 (2011)

#134MissionsPhotographs from lunar orbit show shadows cast by five Apollo flags. The sixth, Apollo 11's, was blown over by the ascent engine as the crew left.Buzz Aldrin saw it go and said so at the time. The five survivors have had fifty years of unfiltered ultraviolet…Lunar Reconnaissance Orbiter Camera imagery

#135MissionsApollo 15 left a small aluminium figure of a person lying down, next to a plaque listing fourteen astronauts and cosmonauts who had died.It is about eight centimetres tall, made by the Belgian artist Paul Van Hoeydonck, and the crew placed it quietly…National Air and Space Museum, Fallen…

#136MissionsCharlie Duke put a photograph of his wife and two sons on the lunar surface at the end of Apollo 16 and took a picture of it lying in the dust.The back was signed by all four of them. He has said since that he assumes it is gone — sealed in plastic, but…NASA Apollo 16 surface photography; Charles…

#137MissionsApollo 17's rover lost a fender extension and threw a rooster-tail of abrasive dust over the crew and instruments, so Houston designed a replacement out of four laminated maps and duct tape overnight.It was clamped on with two lamp clamps from the lunar module. Without it the dust would have coated the radiators…Apollo 17 Mission Report, NASA JSC-07904

#138MissionsOn arriving in Honolulu the Apollo 11 crew filled in a customs form listing their route as Cape Kennedy, the Moon, Honolulu, and their cargo as moon rock and moon dust samples.It is a real document, signed by all three astronauts and by the customs district director for Hawaii, and it was…U.S. Customs and Border Protection, Apollo 11…

#139MissionsApollo 11 left a silicon wafer the size of a coin carrying goodwill messages from the leaders of 73 countries, etched small enough to need a microscope.Each statement was reduced two hundred times over and printed by the same process used for integrated circuits. It…NASA Apollo 11 Press Kit, July 1969

#140MissionsLunokhod 2 drove about 39 kilometres across the Moon in 1973, a distance nothing on another world beat until a Mars rover passed it in 2014.It was driven from Earth by a five-person crew watching low-frame-rate television with a two-and-a-half-second…Karachevtseva et al., Planetary and Space…

#141MissionsThe Soviet Union, the United States, China, India and Japan have all put something down on the Moon in one piece. Everyone else who has tried has crashed.India managed it in 2023 at the second attempt, having lost a lander two kilometres up in 2019; Japan followed in…NASA Space Science Data Coordinated Archive

#142MissionsFire a pulse of about a hundred million billion photons at the Apollo mirrors and, on a good night, one of them comes back.The beam is a couple of kilometres wide by the time it gets there and about twenty kilometres wide by the time it…APOLLO, Apache Point Observatory Lunar…

#143MissionsAn Israeli lander that crashed in 2019 was carrying an archive disc with thousands of dehydrated tardigrades stuck to it in resin.Tardigrades survive vacuum and hard radiation when dried out, and can be revived years later — but only in water…Traspas & Burchell, Astrobiology 21, 845…

#144MissionsChina brought back lava from a plain that turned out to be two billion years old — a billion years younger than anything Apollo returned, and younger than the crater counts predicted.Dating surfaces by counting craters relies on samples with known ages to calibrate the count. Before 2020 the…Li et al., Nature 600, 54 (2021)

#145MissionsSpent Apollo stages and lunar modules were steered into the surface deliberately, so the seismometers already deployed would record an impact of exactly known mass, speed and place.You cannot calibrate a seismic network without a bang you understand, and there are no lunar earthquakes on demand…Latham et al., Passive Seismic Experiment…

#146ObservingA total lunar eclipse is rated on the Danjon scale: 0 is so dark the Moon nearly vanishes, 4 is bright coppery orange with a bluish rim.The difference is Earth's atmosphere. Every ray reaching the eclipsed Moon has been filtered through our air, so…Danjon, L'Astronomie 35 (1921); NASA eclipse…

#147ObservingWhen the Moon passes in front of a star the star does not fade, it vanishes — instantly, because there is no air up there to blur the edge.The disappearance takes a fraction of a second and is startling the first time you see it. Timing occultations was…International Occultation Timing Association

#148ObservingStand in exactly the right place — a track a few hundred metres wide — and a star will flick on and off several times as it grazes the mountains and valleys of the Moon's limb.It is the sharpest way to measure the profile of the lunar edge, which matters because the same profile decides…International Occultation Timing Association…

#149ObservingDuring a total lunar eclipse near sunrise or sunset it is sometimes possible to see the eclipsed Moon and the Sun in the sky at the same moment, which geometrically should be impossible.An eclipse means Earth is directly between them, so both cannot be above the horizon at once. Refraction cheats…Meeus, Mathematical Astronomy Morsels

#150ObservingIn the last seconds before a total solar eclipse the sunlight breaks into a row of separate points, because it is shining through valleys on the Moon's limb.The beads are named after Francis Baily, who described them in 1836. When only one is left the effect is the…Baily, Memoirs of the RAS 10 (1836); NASA…

#151ObservingThe line between lunar day and night creeps along the Moon's equator at about 15 kilometres an hour, and much slower nearer the poles.It follows from a 10,900-kilometre circumference and a 29.5-day day. At the equator you would need a bicycle to…NASA Moon facts

#152ObservingA full moon shines at magnitude -12.7, which sounds dazzling until you compare it with the Sun at -26.7. The gap is a factor of about four hundred thousand.It is why moonlight will not warm you and will not let you read comfortably, despite being bright enough to cast a…NASA Moon facts

#153ObservingThe sunlit Moon is a landscape in full sunlight, so the exposure that works for it is roughly the one you would use at noon on Earth: f/11, shutter speed one over the ISO.Nearly every failed moon photograph is overexposed, because the camera meters the black sky around it and opens…Standard astrophotography practice; NASA Moon…

#154ObservingMoonlight looks cold and silver-blue, and photographs of it come out warm. The blue is in the eye, not the light — lunar rock is slightly redder than the Sun.In dim light the cone cells that see colour give up and the rods take over, and rods are most sensitive to…Purkinje shift; CIE scotopic luminosity…

#155ObservingObservers who care about lunar shadows do not talk about phases. They use colongitude — the longitude of the sunrise line on the Moon — because that is what decides how a crater will look tonight.It runs from 0 degrees at first quarter through 90 at full and round again, advancing about half a degree an hour…Rukl, Atlas of the Moon; BAA Lunar Section

#156ObservingThe length of a shadow, the height of the Sun above the lunar horizon and a little trigonometry give the height of the peak throwing it, and that is how the first lunar mountains were measured in 1610.Galileo had trained as an artist and understood shadows; he worked out that some peaks were several kilometres…Galileo, Sidereus Nuncius (1610)

#157ObservingFor three centuries observers have reported brief glows, mists and colour changes on the Moon. Around two thousand reports exist, and almost none has ever been confirmed by a second observer.Transient lunar phenomena cluster suspiciously around a few famous craters, which is what you would expect if the…Cameron, NASA TR R-277 (1978); Crotts, Icarus…

#158Earth & tidesThe solid Earth has tides too. The rock you are standing on rises and falls by around 30 centimetres twice a day, and you cannot feel it because everything nearby rises with it.Water is only the visible part. The planet itself is elastic enough to flex, and the bulge sweeps round it as the…IERS Conventions, solid Earth tide model

#159Earth & tidesThe ground tide stretches the LHC's 27-kilometre ring by about a millimetre over the course of a day, which is enough to shift the beam energy and has to be corrected for.The crust under Geneva rises roughly 25 centimetres, and the tunnel goes with it. A circumference change of one…CERN Beams Department, LHC beam energy…

#160Earth & tidesThe Moon does not lift the water under itself on cue. Every port has its own lag — hours, sometimes most of a day — between the Moon crossing the meridian and the tide coming in.The ocean is shallow, full of continents, and has its own preferred rhythms, so the tide is less a bulge following…NOAA Tides and Currents, tidal harmonic…

#161Earth & tidesThere are about a dozen points in the world ocean where the tide simply pivots around a still centre, and the range there is close to zero.The tide rotates around these amphidromic points like the hand of a clock, high water sweeping round the rim while…NOAA Tides and Currents; UK Hydrographic…

#162Earth & tidesTides in the Bay of Fundy reach over sixteen metres, not because the Moon pulls harder there but because the bay takes about the right amount of time to slosh.Water rocking end to end in that basin has a natural period close to the 12 hours 25 minutes between high tides, so…Fisheries and Oceans Canada; Garrett, Nature…

#163Earth & tidesIn a few funnel-shaped rivers the incoming tide arrives as a single breaking wave travelling upstream — up to nine metres high on the Qiantang in China, where people have watched it for two thousand years.It happens when a large tidal range is forced into a narrowing, shallowing channel: the front of the flood catches…Chanson, Tidal Bores, Aegir, Eagre, Mascaret…

#164Earth & tidesFriction from the tides drains about 3.7 terawatts out of the Earth-Moon system, which is roughly a fifth of all the power humanity uses, dissipated as heat in shallow seas.That energy comes out of Earth's rotation, which is why the day is lengthening and the Moon is retreating. Most of…Munk & Wunsch, Deep-Sea Research 45, 1977…

#165Earth & tidesLayers of ancient tidal sediment in South Australia preserve the rhythm of the tides 620 million years ago, and counting them gives a day of 21.9 hours and a year of about 400 of them.Tides lay down thicker and thinner bands over the fortnightly spring-neap cycle, so a fossil tidal flat is a tape…Williams, Reviews of Geophysics 38, 37 (2000)

#166Earth & tidesOnce a year, a few nights after a particular full moon, hundreds of coral species along 2,000 kilometres of reef release their eggs within an hour of each other.Corals carry light-sensitive proteins called cryptochromes that respond to moonlight specifically, and the…Levy et al., Science 318, 467 (2007)…

#167Earth & tidesSamoan palolo worms swarm on set nights in the last quarter; Californian grunion come ashore to spawn in the few nights after the highest tides and wriggle back on the next wave.Both are timed to the Moon and both are predictable enough to have a festival or a fishing licence built around…California Department of Fish and Wildlife…

#168Earth & tidesAfrican dung beetles rolling a ball away from a pile keep a straight line by reading the pattern of polarised light the Moon makes across the sky.Moonlight is scattered by the atmosphere into a polarisation pattern centred on the Moon, and the beetles have…Dacke et al., Nature 424, 33 (2003); Current…

#169Earth & tidesDuring the polar night, when the Sun does not rise for months, zooplankton across the Arctic stop following a 24-hour rhythm and switch to the Moon's 24.8-hour one instead.They rise to feed in darkness and sink to hide from predators in light, and with no Sun the only light worth hiding…Last et al., Current Biology 26, 244 (2016)

#170Earth & tidesThe Sun's tidal pull on Earth is about 46% as strong as the Moon's, which is why spring and neap tides differ so much.Tidal force falls off with the cube of distance rather than the square, so the Sun's colossal mass loses out to the…NOAA Tides and Currents, tide-producing forces

#171Earth & tidesIt works both ways. Earth's pull flexes the solid body of the Moon by about ten centimetres, twice per orbit, and that flexing is measurable from here.Because the Moon's orbit is elliptical the pull is not constant, so the rock kneads slightly as it goes round…Williams & Boggs, J. Geophys. Res. Planets…

#172Earth & tidesRainfall over the tropics varies by about one per cent across the lunar month — a genuine, measured effect, and far too small for anyone to feel.The Moon raises a tide in the atmosphere as well as the ocean. Where the air is bulged upward it is very slightly…Kohyama & Wallace, Geophysical Research…

#173Earth & tidesThe tidal barrages at La Rance in France and Sihwa Lake in South Korea generate a few hundred megawatts each, taking their energy directly out of the Earth's rotation.La Rance opened in 1966 and has been running ever since; Sihwa took over as the largest in 2011. Unlike wind or…International Energy Agency, Ocean Energy…

#174Earth & tidesThe Moon has been putting the brakes on the Earth for four and a half billion years. Without it, a day would probably run to something like eight hours.The young Earth turned in about five hours and the Moon has been slowing it ever since; the Sun's tides alone would…Touma & Wisdom, Astronomical Journal 108…

#175Strange but trueClocks on the Moon run about 56 microseconds a day fast, so the White House told NASA in 2024 to define a separate standard called Coordinated Lunar Time.Weaker gravity makes time pass fractionally quicker, exactly as general relativity says. Fifty-six microseconds…US Office of Science and Technology Policy…

#176Strange but trueA rock some tens of metres across called Kamo'oalewa keeps pace with Earth around the Sun and has done for about a century, and its colours match lunar rock rather than any asteroid.It is a quasi-satellite: not in orbit around Earth, but locked into the same year, so it appears to loop around us…Sharkey et al., Communications Earth &…

#177Strange but trueEvery so often Earth's gravity grabs a passing rock a metre or two across and it goes round a few times before escaping. Two have been caught in the act.2006 RH120 stayed for about a year; 2020 CD3 for roughly three. Models say there should be one metre-sized minimoon…Fedorets et al., Astronomical Journal 160…

#178Strange but trueThe Outer Space Treaty of 1967 says no country can claim any part of the Moon. That has not stopped one company selling certificates of ownership to what it says are six million customers.The treaty binds states, and the usual argument for selling plots is that a private individual is not a state. No…Treaty on Principles Governing the Activities…

#179Strange but trueStand anywhere on the near side and the Earth stays put in the sky. It does not rise, it does not set, it hangs in the same spot and slowly changes phase.The Moon turns once per orbit, so the Earth stays fixed above whichever point faces it. It nods around a little …NASA Moon facts

#180Strange but trueFrom the Moon, Earth is about four times wider than the Moon looks from here and roughly forty times brighter, and it goes through phases opposite to ours.When we have a new moon, they have a full Earth, which is why the dark part of a young crescent glows: it is lit by…NASA Moon facts

#181Strange but trueWith no air to scatter light, the Moon has no twilight. The Sun goes below the horizon and the landscape goes out.On Earth the sky stays lit for the better part of an hour after sunset because the atmosphere above you is still…Apollo Lunar Surface Journal; NASA Moon facts

#182Strange but trueThe lunar sky is black at noon, and the stars do not twinkle, because twinkling is something our atmosphere does rather than something stars do.Blue sky is sunlight scattered by air; no air, no sky. The stars are up there in full daylight, but the ground is…Apollo Lunar Surface Journal

#183Strange but trueThe Moon's far side is permanently shielded from Earth's radio noise by 3,500 kilometres of rock, which makes it the best place in the inner solar system to listen to the early universe.Low-frequency radio astronomy is nearly impossible from Earth: our ionosphere blocks part of the band and our…NASA Lunar Surface Innovation; Chang'e 4…

#184Strange but trueThe US Army bounced radar off the Moon in January 1946 and got an echo back 2.5 seconds later, and radio amateurs have been holding conversations the same way ever since.Project Diana was the first proof that a signal could get through the ionosphere and back, which is the whole basis…US Army Signal Corps, Project Diana, 10…

#185Strange but trueIn 1958 the US Air Force commissioned a study on detonating a nuclear device on the Moon, mainly so the flash would be visible from Earth and would make a point.It was called Project A119 and the paperwork stayed classified until 2000. A young Carl Sagan was on the team…Reiffel, A Study of Lunar Research Flights…

#186Strange but trueOf the twelve people who walked on the Moon, exactly one was a scientist: Harrison Schmitt, a geologist, on the last flight.Every other moonwalker was a test pilot, trained in field geology for the job. Schmitt was added to Apollo 17 after…Apollo 17 Preliminary Science Report, NASA…

#187Strange but trueBefore the first moonwalk, Buzz Aldrin took a small communion kit out of his personal preference kit and celebrated it inside the lunar module, and said nothing about it on the air.NASA was being sued at the time over the Apollo 8 crew reading Genesis, so he was asked to keep it off the…Aldrin, Guideposts (1970); Apollo 11 onboard…

#188Strange but trueA ceramic chip the size of a thumbnail, carrying drawings by six artists including Andy Warhol and Robert Rauschenberg, was reportedly smuggled onto Apollo 12's descent stage by an engineer.The story is that official permission was requested and never came, so an engineer at Grumman attached it quietly…Myers, Interviews with the Moon Museum…

#189Strange but trueNixon gave fragments of Apollo rock to 135 countries and all fifty US states. By 2002 about 160 of them could not be found.They were mounted on plaques and handed to heads of state, and then governments fell, offices were cleared and…Gutheinz, Operation Lunar Eclipse; NASA…

#190Strange but trueNothing orbits the Moon naturally, and nothing could for very long. Anything captured gets pulled apart between Earth's gravity and the Moon's own lumpy field.The region where the Moon's gravity wins over Earth's stretches about 60,000 kilometres, which sounds roomy, but…Ely, Journal of the Astronautical Sciences…

#191Strange but trueThe Moon is 3,475 kilometres wide — about the distance from London to Cairo, or a little less than the width of the contiguous United States.It is a quarter of Earth's diameter, which is a ludicrous ratio for a planet and its moon: nothing else in the…NASA Moon facts

#192Strange but trueTurkey, Pakistan, Tunisia, Algeria, Malaysia, Singapore, Mauritania, Azerbaijan and several others fly a crescent, and Nepal flies both a moon and a sun.The crescent predates Islam by a long way — it was a symbol of Byzantium, on coins, centuries before the Ottomans…Constitution of Nepal, Schedule 1; standard…

#193Strange but trueA law signed at the end of 2020 requires any American mission licensed to land near an Apollo site to keep its distance and leave the artefacts alone.It cannot make the Moon a national park — the Outer Space Treaty forbids claiming territory — so it works through…One Small Step to Protect Human Heritage in…

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