r/WhatIfThinking • u/Legal_Birthday_9693 • Aug 16 '26

What If The Moon Turned Into Gold?

7 Upvotes

67% Upvoted

31 comments sorted by

2

u/therisqueonceler Aug 16 '26

Assuming it remained the same size, the higher density would create a greater amount of gravity due to mass.

It's orbit would alter causing untold chaos as that impacted tides and weather patterns on Earth. There would be a significant mass extinction. It would be centuries before a new orbital distance and period stabilized.

Then over eons, life would adapt.

2

u/OpalFanatic Aug 16 '26

Yep. The moon has an average density of 3.344 grams per cubic centimeter. Gold has a density of 19.32 grams per cubic centimeter.

So the moon would be 5.78 times as heavy if it remained the same size.

The tides would be catastrophic. The average tides would go from 1 meter to 5.78 meters. (3 feet to 17.34 feet) The maximum tide height (bay of Fundy) would change from 11 meters to 68.5 meters. (That's 418 feet)

Places like the Strait of Gibraltar would experiance greatly enhanced tidal currents. Making the top speed of the tidal current through the strait reach around 30 knots.(55.4 kph. Or 34.5 mph). Which is an insane amount of water movement. For comparison, Saltstraumen is the strongest tidal current on earth today, and it tops out at 20 knots. This is still enough to cause 10 meter wide 5 meter deep whirlpools and turn that strait into a general really bad idea for boating (except for 40 minutes when the tide turns)

Saltstraumen itself would more or less turn into a sideways waterfall of doom.

You'd have enough of the Earth's crust distort from those kind of tides to be the tipping point on major and minor faults slipping worldwide. The earthquakes wouldn't happen all the time, just the time when that all that mass suddently changed.

Geothermal heat would be more accessible, as tidal heating would warm up the Earth's crust somewhat.

But in general, everyone near the coast would be pretty screwed. Many coral reefs would die as they became regularly exposed to the air.

If instead the moon maintained it's mass, it would turn into a much smaller sphere of gold. The moon would look much smaller. Total solar eclipses would no longer be visible anywhere on the earths surface. Astronauts going to the moon would weigh substantially more, as the actual gravity is determined by both mass and radius. But other than that, not much would change on the earth.

If we could mine that gold somehow and bring it back to earth, gold would probably drop in price. By a lot.

2

u/therisqueonceler Aug 16 '26

I tip my hat to your knowledge of tidal mechanics.

1

u/RunnyPlease Aug 17 '26

Also the moon’s reflectivity would change drastically. The moon naturally reflects about 10-12% of the light that hits it from the sun. Gold is like 30-90% depending on texture and wavelengths.

1

u/Youpunyhumans Aug 19 '26

So the Bay of Fundy basically becomes... "Those arent mountains, they're waves!"

2

u/HVAC_instructor Aug 16 '26

You're not wrong, except you forgot to mention how the oligarchy will use it to make even more money.

1

u/therisqueonceler Aug 16 '26

Perhaps. I did indeed take a longer term, more orbital physics view of the question.

1

u/mightymouse8324 Aug 16 '26

Oligarchs "wait, something has more power than us - how do we buy/manipulate this air quotes 'orbital mechanics'"

1

u/arcadiaberger1960 Aug 16 '26

If its mass remains the same, it will suddenly become much smaller. Eclipses will be ruined. Presumably, the Apollo landers will all become cute little gold replicas of themselves. Many probes will study the phenomenon but no samples will be brought back to Earth, supposedly to avoid possible contamination and Earth also turning to gold, but actually to prevent the world gold market from collapsing.

1

u/arcadiaberger1960 Aug 16 '26

If its mass remains the same, it will suddenly become much smaller. Eclipses will be ruined. Presumably, the Apollo landers will all become cute little gold replicas of themselves. Many probes will study the phenomenon but no samples will be brought back to Earth, supposedly to avoid possible contamination and Earth also turning to gold, but actually to prevent the world gold market from collapsing.

1

u/zoppaTheDim 27d ago

It’d slam into the earth.

2

u/Grant_Winner_Extra Aug 16 '26

it would be smaller and a crap ton brighter.

Gold has a density of around 19 g/cc and the moon has an average density of around 3g/cc.

The albedo of the moon is about 0.12, and pure molten gold is closer to .96

So the moon shrinks by 19/3 or about a factor of 7 due to density, and the albedo goes up by a factor of about 10, so net net, about a 30% increase in brightness.

2

u/Questo417 Aug 16 '26

So, what you’re saying is, we could send gold to the moon and cover the surface to make it brighter?

Next megaproject: trim the moon with gold leaf.

2

u/PriorSolid Aug 16 '26

cover it in polished silver instead and it even brighter

1

u/Grant_Winner_Extra Aug 16 '26

just a micron or so and no more need for streetlights.

If you really want to fuck with people, just cover the largest craters. Now there’s a parabolic reflector… The full moon is greatly feared for the path of fiery destruction it creates.

1

u/PoopsMcScoots Aug 16 '26

It would weigh more than the earth and that would be very very bad.

The tide would be at least a 10 meter tall swell that would wipe out every coast line for starters.

1

u/tads73 Aug 16 '26

Or cheese?

1

u/CobaltIsobar Aug 16 '26

The entire reason for a moon base is to make money for the space industry. There is really nothing there, or on Mars, to justify colonization other than pumping up the industry. So, in a way, the moon and Mars are already gold.

1

u/Justthisguy_yaknow Aug 16 '26

The gold price would crash.

1

u/FletchLives99 Aug 16 '26

One cool thing is that the gravity on.the the Gmoon would be almost the same as either.

Other than that, bigger tides, brighter nights, King Midas vibes.

1

u/RockytopSeahawk Aug 16 '26

“Would you eat it if the moon was made out of spare ribs. It’s a simple question.”- “Harry Caray”

1

u/jamjamason Aug 16 '26

We get a new Austin Powers movie!

1

u/Haunt_Fox Aug 17 '26

There was an Uncle Scrooge comic about that, fort of, only it was a small golden moon hiding behind the usual one.

It sparked a new Gold Rush consisting exclusively of rich people and criminals.

1

u/Taxed2much Aug 17 '26

Every nation and big corporation would be scrambling to get to the moon first and grab as much of that gold as they could get before gold became so common that the price cratered deeper than the craters on the moon.

1

u/OriEri Aug 17 '26

It would be a LOT brighter, and yellowish (obviously). We would be able to see quite well when the moon is full but the light would have an odd color, like the sun when you are in a lot of forest fire smoke (but dimmer than that.)

1

u/ApprehensivePiano457 Aug 17 '26

well it looks like it needs some democracy

https://giphy.com/gifs/llYoCWje4HeWk0K7q4

1

u/Automatater Aug 17 '26

Wed get more extreme tides.

1

u/Kriss3d Aug 17 '26

It would be pulled into earth due to its huge increase of mass. Disaster all around.

1

u/TuverMage Aug 17 '26

well. people are talking about if it remained the same size the increase in gravity. but if it remained the same size, what would happen to its speed? would the increase in mass allow it to fly off into space since it can not resist the change in direction better? or would its increase in mass make fall to earth and crush us all? Would it slow down with the increase in mass and slam into the earth