# [Request] People were arguing over the percentage in the original comment section. Math has never been my strong suit, so does anyone wanna crack at it for me?

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Population of earth: 7.674 Billion 1% population of earth: 76.74 million population of Australia + Hawaii: 26.776 million Papua new guinea and other micronesia/polynesia/oceanic islands adding perhaps another 15 million The issue is how much of Indonesia is included with a population of 270 million. If more than around roughly 35 million of the 270 million Indonesians are included in the dark zone, less than 99% of Earth's population are in the light and the image is wrong. ​ ^(edit: I could find out, but nasa seem to have shut down SEDAC or it's columbia.edu host is ddos'd - and I don't have the time to plot and add up Indonesian town/city populations from wikipedia manually. My inclination is that the image is wrong, and the percentage is more like 97.5%

The regions of Indonesia completely in the dark on this are: Southeast Sulawesi - 2,624,875 North Sulawesi - 2,621,923 East Nusa Tenggara - 5,325,566 North Maluku - 1,278,864 Maluku - 1,848,923 You also didn't account for East Timor which is another 1,340,513 million people. In total that's 15 040 664, well below the 35 million cutoff. However, you could make the argument that parts of South Sulawesi ought to be included too, which is very densely populated compared to the other regions. Only a little bit of it appears to be in the dark area but as a ceiling I'm going to add the full 9,073,500 just to be sure. This puts it at 24 114 164 people, which should fit fine still. I also decided to double check your "other islands" estimates and they came out to be around 17 396 378. In total that is 68 286 542, which is indeed less than 1% of the population of Earth. Sourced from google maps and wikipedia: https://en.wikipedia.org/wiki/Pacific_Ocean#Bordering_countries_and_territories https://en.wikipedia.org/wiki/Provinces_of_Indonesia

You forgot West Papua and Papua Provinces, which is another 5,5 mil people.

Good point, that makes 73 724 317 total

The ability to draw polygons and then GIS overlay population using the NASA map would solve this with the highest accuracy. We're below 99% it's just a question of how much below it, ideally want below 98.5% to debunk it so they can't say it's rounded. Given that twilight is dark enough that you would still consider it night time though, it's just debate for the sake of debate at this point Then further debate about levels of darkness only settled by going down there on the 8th of july and seeing when the light sensor turns the street lamps off š

I think you overestimate the presence of light sensors. It could just be some guy flipping a switch.

Nosferatu!!

Parasite reference?

No. Do share though.

I meant the movie. And itās a bit of a spoiler... so I probably shouldnāt mention more.

Stick to time of sunrise/sunset for simplicity.

Civil, Nautical, or Astronomical sunset? Civil sunset is when the sun is 6 degrees below the common horizon, but there is still light in the sky. Nautical sunset is when the sun is 12 degrees below the common horizon, but there is still light in sky. And Astronomical sunset is when the sun is 18 degrees below the common horizon, but there is still (very little) light in the sky. The common horizon and the actual horizon varies depending on where you are standing. If you are on a boat at sea in calm weather, the common and actual horizon are the same thing. If you are on land surrounded by hills, the common and actual horizon varies widely.

Im not doing the calcs for any of it! If you want to add population densities at different altitude to the mix, feel free. Id suggest just go with a simple spheroid model with typical mean heights of the main population centres.

I think most people would define sunset as the point in time when you can no longer see the sun over the horizon. Whether that's the correct point to use, I don't know, but I can't imagine any other definition of sunset being useful for this problem. And yes I know the definition I gave is vague and changes based on atmospheric conditions and such, but a flat degree measurement will be very wrong in many cases

>the point in time when you can no longer see the sun over the horizon. The problem with that one is that two people can be in the same "place," and one will still see the sun, while the other will not based on their difference in altitude.

The image indicates "sun light" specifically, meaning that light refracted after sunset still counts. Presumably light reflected off the moon is just a peavish technicality, but i think residual light after the sun is below horizon is fair game.

I was starting to consider that some cities would be in the shadow of mountains at certain times, some people would be working in mines, or indoors. Full geoid model, total population tracking and set standard of level of illumination or reference to standard sun position ignoring atmospheric distortion is the only way to be sure.

yes, gotta be absolutely certain

If we are talking about how 'bright' the sun is depending on twilight times, what about places with serious cloud cover? Black clouds where it's darker than twilight. Rare, but this is a lot of the world's surface area. Surely it's near impossible to figure that out unless we have a weather map for that time.

There's a case for it, the sun sets twice in some places it feels like. Once when the weather rolls in and once again later

r/theydidthemonstermath

I love each and every one of you guys. You are amazing. ā¤

Most of Indonesia's population is centred around the islands of Sumatra and Java which are on the western side and as such more in the light area than the dark. Java has 150m people and Sumatra has 50m.

That would still leave 100m on the east, only 35m needed to tip it below 99% and an additional 65m would be almost another entire percentage point which is why I put it at around 0.5% either side of 98% at an estimate It gets more complicated when you try to figure in how much light is necessary for it to be light. Those lines which are neither light nor dark on this particular map represent the different stages of twilight (civil, nautical, astronomical) and since they are technically below sunrise/sunset then they could also be considered dark. If we're including those (my original math didn't) now we're including California/western USA as well as much more of Indonesia as dark pushing it well below 95%

I spent a lot of time in China. About 25+ years ago I was in Hong Kong and China was preparing for another census. I was told that they expected 1.35bn but the rounding error was +-50m due to the roaming worker population. I live in Australia where our population is only 25m, half their rounding error. That's why most countries are viewed as irrelevant to their government

uh sentence structure, 'their government' is the PRC or 'most countries'?

PRC. I think the sentiment is that China doesn't spend much time considering the interests of groups of people smaller than the rounding error of its own population. Only a handful of other states might produce a meaningful impact on the Chinese government's plans owing to the gdp and population numbers of most countries being insignificant at China's scale.

The best way to go around doing Indonesia is probably just eyeballing which [provinces](https://en.wikipedia.org/wiki/Provinces_of_Indonesia) are in the sun.

I guess NZ doesn't exist. I mean, it's only 4.8 million people, but c'mon man.

Tbh I'm impressed NZ even made it onto the map. Most of the time the cartographer draws Australia then knocks off and goes down the pub. /r/mapswithoutnewzealand

That just isn't true at all.

I feel like you just made some of these population figures up. Papua New Guinea plus New Zealand alone gets you fairly close to the 15 million for "rest of the Pacific". Then there's *actually* the rest of the Pacific, plus the proportion of Indonesia. I suppose I was thrown by you saying Australia and Hawaii are the major players population wise when Hawaii has only one and a half million, which is a lot less than New Zealand and Papua New Guinea. According to Wikipedia there are about 41 million people in Oceania (which does not include Hawaii or the portion of Indonesia that is in this picture.

Well it depends if we're talking geography or people. I mentioned Australia and hawaii to define the area which is definitely in shadow at no point did I talk about how significant a player they were? The pacific islands are the places in between. Oceania includes Australia, so you've counted that twice (it's the continent). I mention polynesia/micronesia/PNG because they are dark and in close proximity *but* not Indonesia in this part because Indonesia is in Asia, not Oceania. Despite Indonesia being many islands and geographically similar (it's on the pacific fault line), so included separately since that's where the sun line is drawn and 26+15 **is** 41?

But basically isnt it almost the same to say 99% or 98.5% of the population? the error margin seems to be to small to be significant in a non scientific conversation right?

I mean, when we're talking about 38.3 million human lives it pays to be accurate. Really had they just claimed 95% or 97% that's still very impressive alone and nobody would have bothered to fact check likely Their claim was a threshold claim though, they said 99-100%

Yeah we don't count aust*ralians as people

You astronomical thundercunt

Fuck of r/teenagers user

What about the people in Antarctica?

[ŃŠ“Š°Š»ŠµŠ½Š¾]

Is that taking into account the fact that sun is only the brightest bit (and the darker but still light bits correspond to twilight)? I think there are some Chinese coastal cities that'd get cut off there

For sure the twilight is counted to the sunlight. Haven't calculated, but seeing as the twilight accounts not only for coastal china, but also half of usa mexico, central america, peru&chile&surroundings, the koreas and the most populous islands on earth, java and all of japan... thats gonna add up to over half a billion for sure!

https://www.timeanddate.com/worldclock/sunearth.html?month=07&day=08&year=2021&hour=11&min=15&sec=0&n=&ntxt=&earth=0 So, if you look at the map, the shaded areas are different levels of twilight. Meaning there is some sunlight, however, the model would have to mean there are no mountains. Los Angeles, and other CA coastal cities, would be in Astronomical twilight, and thanks to lots of mountains, might not actually get much sunlight. https://www.timeanddate.com/astronomy/astronomical-twilight.html It's semantics, but it wouldn't be completely accurate to say 99%. I tried to find a globe version of sunlight, but i couldn't.

I think it would make sense to count it as sunrise and sunset times across the world. Not sure if that affects it or not, but that saves us from debating on the sunlight being blocked by terrain and buildings

Astronomical twilight correspond with the angle of the Sun not the amount of light. I think saying thereās any perceivable light to the human eye at 4:15 AM on the west coast of the US is an overstatement.

agree, the sky being light without the sun overhead isn't day time, it's night. Seeing light in the sky isn't the same as being cast in light The sky is different shades overnight depending on cloud anyway so not all nights are completely black. But in the morning or late at night after the sun has set, nocturnal creatures are out, everything is silhouettes and you can barely see to walk without holding a light. That's got to be 'dark' you can't recognise people in front of you by sight, you can't do anything, if you were driving your headlights would be on etc

What? No attempt at math at all? Just commenting with "Yeah, I guess"?

r/theydidntdothemath/

Indonesia is the 4th most populous country...

The bulk of Indonesia's population is in twilight on this map and so is counted as receiving sunlight

I'm pretty sure eastern Indonesia has more population than any of those except Australia

Yes Australian love the darkeness, yes

Can confirm. Am Aussie, itās currently dark and I like it.

I always figured that in the daylight, the spiders see you coming.

Bullshit, I can see the lights on at your house.

Australia barely has a population.

[ŃŠ“Š°Š»ŠµŠ½Š¾]

You sure?

Uhhh, do you even know where New Zealand is??? I can see it clearly in that map on the bottom right.

Bro, that's clearly just South Japan

I do sometimes refer to it as East Tasmania if I want to piss off a kiwi.

If it happens on the 8th of July (after the solstice), would this also not happen at the same number of days before the solstice too? 4th of June by my count.

No because the earth inclination is the other way

Shouldnāt this also happen on the other side of the solstice? About June first or so? It should almost be symmetrical with July 8.

The summer solstice isn't even on the same day each year, which raises a bigger question to me about the caption - why would it happen at the same time to the minute each year when the solstice shifts by up to a couple days between different years.

I am ok with the time of day, since it is at that time where the sun will cover the particular land with the most people. And the amount of land may change from year to year, since the exact time of the solstice changes. Then if the solstice changes enough, it may push the day to July 7 or 9. But the same time GMT. And since we did not have the skip of leap year in 2000 like most century marks (skip, a once in 400 year event), we are adding more time to the shift of all celestial events until a correction in 2100. Still should be another around June 1. Edit... On second thought, the position of the sun is a celestial event too. So by my own words, I must agree with you. The time should change slightly year to year. And maybe even jump a day once in a while.

I know technically twilight is "receiving sunlight" but it kinda feels like cheating to me. When you see stats of average hours of sunlight for a region it doesn't count twilight. To me receiving sunlight means the sun is shining directly on an area.

I mean how objective do we want to be? How many of those people who live in the sunlit area didn't see sunlight at that specific time? People who were sleeping, people who were just indoors with no natural light, the list goes on. It must be impossible to get this absolutely correct but 6.5 percent of people in the US do night shift (I can't find figures on the world but let's use that for arguments sake) - it's hard to know how many of them would be asleep at that time depending on where they were in the world (what time it was). But if at least half of them were (and we aren't accounting for people with zero natural light while being inside - that drops the percentage to AT MOST 95.5 percent of the world's population seeing daylight. More accurately we could say roughly 90 percent.

Pretty sure for the question its people who could get some sunlight if they were awake and went outside. And by sunlight it may be after sunset but not completely dark outside yet.

Didnāt mean it to be that reductive but I like your ability to think outside the box.

Cheers

Well technically every country gets sunlight all the time because it gets reflected off the moon (I'm just being a smartass idk the math lol)

Havenāt done the math as well, but [they](https://skyandtelescope.org/astronomy-resources/astronomy-questions-answers/shouldnt-a-perfectly-reflecting-full-moon-be-just-as-bright-as-the-sun/) did