Jets produce mostly low‑frequency sound. Low‑frequency sound spreads widely and is hard for human ears to locate due to the timing of the wavelengths entering your eardrums. This is also why bass always feels like it’s everywhere at concerts.

You don't need a 'firmament' for this echo to occur; it's just the result of insanely fast, and loud, movement paired with low frequency sound waves.

This is an optical illusion caused by the sheer brightness of the Sun and the transparency of the clouds. If the clouds infront of the sun are just transparent enough, the immense brightness of the Sun can cause us to not see the clouds infront of the Sun.
Here's someone's experiment demonstrating this phenomenon in detail. Below is an image of the experiment:

Early geocentrist astronomers used heavily complicated maps to make up for their error in thinking the Sun goes around the Earth. Normal, real maps are way easier to use in finding out the path of planets.

This is how we are able to predict solar eclipses hundreds of years into the future with precision down to the second. We use the REAL world model, a ROUND Earth.

The Romans knew, the Greeks knew, even Jesus probably knew. You're the odd one out if you think it's flat.

Stellar parallax is a well-documented phenomenon, but it's so minor because the stars are so far that we can't detect any change with the naked eye. Claiming that there's no parallax in stars is a fool's mistake, a completely false statement. The Greeks used this same argument against heliocentrism because they didn't know just how far away the stars really are.

The closest star to use is Proxima Centauri, which is about 4.24 light-years away. We can't even see the parallax on this with our human eyes: a mere 3.85 arcseconds/year which translate to 0.001069444 degrees/year or 0.00000292797 degrees every DAY.

See a video of Proxima Centauri's parallax over 10 years with highly specialized equipment.

If I'm in the Southern Hemisphere, why can't I see Northern Hemisphere constellations? The Polaris of the South is the Southern Cross. You CANNOT see the North Star from the South, which makes 0 sense on a Flat Earth.

If I'm looking South on a Flat Earth, it means I'm looking outwards towards the 'ice wall.' How is it possible that someone on the other side of the Flat Earth sees the same constellations as me looking in an opposite direction? Clearly impossible, and a massive disproof of Flat Earth.

To put it simply, you can see farther when you're taller because your eyes can see farther beyond the curve. Second, if something is beyond the horizon, you can still see it! Its height just has to be taller than the horizon. Basically, things don't drop into nothingness instantly, you can still see part of them if they're beyond the horizon, and your height allows you to see farther.

If you are comfortable with math (which most conspirators probably aren't), I'll walk you through the calculations behind how far you can see.

The graph of a partial circle is y = √(r^2-x^2), we can replace the r with E and that gives us part of the Earth. You can graph this into Desmos to confirm that this is indeed a hemisphere with a radius of E.

Now imagine you are standing right on the top of the Earth, standing 6 feet tall, looking straight down at the horizon. We need to find the equation for the line whose y-intercept is equal to E+H and is tangent to the Earth, meaning it touches the Earth's curve. This will be our line of sight looking straight at the horizon.

This just means our line starts at E+H, the top of the Earth plus 6 feet and is looking downwards at some slope A that we need to find.

We want one solution, so recall the quadratic formula: x = (-b ± √(b^2 - 4ac)) / (2a)

The b^2 - 4ac has to be 0 so the -b plus or minuses a zero, leaving us with a single solution for x.

Plugging this into Desmos with A replaced with x gets us a value of ±0.00075767. I'll use the positive value since I already made A negative in the y = F - Ax equation.

Now I couldn't get Desmos to give me an exact number, maybe because of the scale, but x = 3 is about where the curves intersect, which means a 6-foot-tall person can see 3 miles.

However, that is only up to the horizon; imagine if you're looking at an object that's 10 feet tall. If it's standing right on the horizon, you can see it in its entirety, and only when it goes beyond it will the bottom of it start to disappear from your line of sight.

Ok let's calculate this for an object of size 10 ft. The top of the object lies on the curve y = √((E+O)^2-x^2), increasing the normal radius of the Earth by 10 feet.

We can use the previous calculations for our line of sight to find out where the intersections are between our line of sight and the top of the object, telling us when it disappears.

Plugging this into Desmos outputs two x-values, the larger one (when it goes out of our line of sight) is 6.87204 miles.

Using the 8 inches per mile argument for this, we'd get a drop of 31.4832892 feet, and you can see why someone might say 'oh well 31.5 feet? We shouldn't be able to see objects 10 ft tall over the horizon!' But it fails to understand that you also have height and can see pretty far, seeing objects in their entirety all the way up until the horizon until they start disappearing bottom first where we can still see the top of them. And don't forget the bit of viewing distance we get with atmospheric refraction.

Anyways, there it is, mathematically showing you that you can indeed see objects of size 10 ft 6 miles away on a round earth. Hard numbers, not soft ones with vibes.

The photos of Earth are taken with a variety of cameras which all take in light differently, and it will change how the final picture is. Simply look at old photos even ON Earth; their colors are far weirder than what we have today. You cannot claim the photos are fake because of a color difference in 1997 to 2016, that would be idiotic.

Second, these photos aren't taken with one single camera far out in space; these are COMPOSITE images, meaning they took a bajillion images with satellites CLOSE to Earth, and stitched them up together after-the-fact, which is why the continent proportions aren't 100% accurate in these images.

Space video deniers like to say that the videos are actually made underwater or in a studio. But that logic makes absolutely zero sense. Even a child can understand that you'd see bubbles and other signs of water in a studio environment. How are they even breathing if it was underwater? So stupid. I don't know how many conspirators believe this because it's so ridiculous, but there probably are because obviously they don't think too deep.

Some people like to say that it's filmed with a green screen inside of whatever the hell studio can mimick 0G, maybe a plane? But tell me how there's never been artifacts in the videos caused by the green screen? Surely there would be some kind of visual evidence if that were the case. Sure modern editing is powerful, but would it really leave zero trace after THOUSANDS of videos? Even so, let's say they are REALLY good at editing. Moon landing deniers love to say 'well there's no stars in the Apollo video, therefore NASA sucks at editing.' You can't have both be true.

Nostradamus was a French astrologer and physician who lived in the 16th century. He is best known for his prophecies, which were written in obscure language and often interpreted in various ways.

Many people believe that Nostradamus predicted the events of the 20th century, including the rise of Hitler and the atomic bombings of Hiroshima and Nagasaki. However, there is no evidence to support these claims.

Here's some of the quotes I found about his 'prediction' that I will individually challenge:

Let me make it clear that Nostradamus was born in 1503 and died in 1566. Steel wasn't invented until the 18th century, 200 years after his death, so it's impossible that he could have even USED the word 'steel.' Clearly, this quote is fabricated (which it is but I'm sure conspirators would never believe that).

Furthermore, the quote does not mention the Twin Towers specifically, nor does it mention the date of the attack. It is clear that this quote is fabricated.

You need to understand how psychics work before I can delve into this quote: psychics use very vague language to make their predictions. They use very broad terms and often use metaphors or symbols to convey their meaning. This leads to many people thinking they really do predict the future because they got a better christmas bonus or something and the psychic said 'you will have a great holiday this year' 25 months ago. This quote is a perfect example of this.

Do you really think NY, one of the worst places I can imagine, is the "city of God"? And what the hell is the "fortress"? Who is the "great leader"? I've never heard of a great leader fall after 9/11 nor did I hear anything about a fortress. And say what you may about "oh this is the start of World War 3" buddy World War 3 hasn't happened for ages. You can keep saying we are in WW3 but just because there's some conflict going on (which ALWAYS happens) doesn't mean it's a WORLD war.

And third, this quote claims it was penned in 1654, but Nostradamus was already dead 88 years ago. This is so blatantly a fake quote.

How many new cities are there? There's New Mexico, New Orleans, New York, New Jersey, New Hampshire, etc. This could apply to any one of those. Second, planes aren't flames from the "core," they're in the sky.

Governments can barely hold any secrets. Government secrets are so easily leaked, especially in a free country like the USA.

People were scared of government surveillance after 9/11 BECAUSE a government agent named Snowden leaked government files detailing the NSA's surveillance methods.

Ellsberg leaked Pentagon papers detailing how the government was misconstruing the Vietnam War as a series of American victories.

President Nixon destroyed evidence, silenced witnesses, and obstructed investigations, but even that didn't stop the world from finding out that he'd been behind the Watergate break-ins.

It is so hard for the government to hide any secrets, do you really think something as big as the shape of the world or the moon landing could be faked and kept secret? Even when history demolishes your bullshit beliefs?

This one of the most ridiculous claim I've ever heard. As a software engineer, I can tell you plainly that we don't even have the compute power to simulate a single fly brain. How the hell would we have a nanochip with the power of seven billion human minds? Do you have any idea just how powerful the human brain is?

Also, the LHC smashes particles together at high speeds to see what happens. It doesn't open portals to hell. This is just pure fantasy. Like please think with your brain: if the scientists could talk to the devil, they'd be publishing about it EVERYWHERE. Do not underestimate just how clout-chasing researchers can be.

Some of you might say 'but Ybg, you dumb ignorant idiot, CERN scientists, who are supposedly separate from religion, were seen practicing a mock human sacrifice infront of the Shiva statue!' First of all, many scientists are religious. Religion is an unprovable explanation for things that are beyond science. Science deals in the realm of provable things. There is nothing about religion that would stop someone from being a damn good scientist. Second, that mock ritual was literally a prank done by outsiders, not CERN researchers.

Some of you might say 'oh but why do they even have a Shiva statue?' Well, the Shiva statue is a symbol of destruction and rebirth, which is relevant to the scientific process of smashing particles together. It's not about practicing human sacrifice or any kind of religious ritual. You can have Shiva statues without even believing in Shiva, symbols are just cool.