Okay so I've been hearing for a long time that the reason we get a solar eclipse is because the moon is 400 times smaller than the sun, and 400 times closer to us. Hence it eclipses the sun perfectly in certain locations at times.

Think about it for a minute. You can fit 1.3 million Earths in the sun, so that means the sun is 1.3 million times bigger than the Earth. If the moon is 400 times smaller than the sun, then wouldn't the moon be almost the size of JUPITER??? 400 times smaller is a bullshit number. There's no way that the moon is 400 times smaller than the sun. If it was, it would gravitationally destroy the Earth.

You're right about the phrasing. I've heard these two things before and it's indeed semantic nonsense when you put the two together. The sun in size is 1.3 million Earths but 400 moons? That suggests how many earths in the moon? (yes not the other way around).

Might be worth finding sources that say the two things, canvas them together and showing the lunacy between them.

Ha well I was wrong. According to Stellar, here's how it works:

You’re totally right to flag the confusion—two different kinds of “size” got mixed.

What “400×” really means

Diameters:

Sun ≈ 1,392,700 km

Moon ≈ 3,474 km

Sun/Moon diameter ratio ≈ 1,392,700 / 3,474 ≈ 402 → “~400× bigger (in diameter)”

Distances (from Earth):

Sun ≈ 149,600,000 km

Moon ≈ 384,400 km

Sun/Moon distance ratio ≈ 149,600,000 / 384,400 ≈ 389 → “~400× farther”

Because apparent size ≈ physical diameter ÷ distance, those two ~400s nearly cancel, so the Sun and Moon look about the same size in the sky—hence total/annular solar eclipses.

Where the “1.3 million Earths” fits

“You can fit ~1.3 million Earths inside the Sun” refers to volume, not diameter.

Volume scales with the cube of diameter. If something is ~400× larger in diameter, its volume is about 400³ ≈ 64 million times larger.

Actual numbers:

Sun/Earth volume ≈ 1.3 million

Sun/Moon volume ≈ ~65 million (consistent with ~400× diameter difference)

Moon vs Earth (to address the “Jupiter-sized Moon” worry)

Moon is ~27% of Earth’s diameter and ~1/81 Earth’s mass.

Jupiter is ~11.2× Earth’s diameter and ~318× Earth’s mass—completely different scale.

So the “400× smaller” claim is not saying the Moon is 1/400 the Sun’s volume or that it’s Jupiter-sized; it’s specifically about diameter relative to the Sun, paired with distance.

Quick angular-size check (why eclipses work)

Sun: 1,392,700 / 149,600,000 ≈ 0.00931 rad ≈ 0.533° (~32 arcmin)

Moon: 3,474 / 384,400 ≈ 0.00904 rad ≈ 0.518° (~31 arcmin)
Those overlapping ranges are why sometimes the Moon exactly covers the Sun (total eclipse) and sometimes leaves a ring (annular), depending on perigee/apogee.

Bottom line:
“~400× smaller and ~400× closer” is a good rule of thumb for diameters and distances, which explains eclipses. The “1.3 million Earths” is about volume, so it doesn’t contradict the 400× diameter fact.

Volume vs diameter. Good point.

Mind you it's still poor wording for anyone to say (400 * smaller). Smaller implies percentage of volume. Simple word change "400 * wider" would have given resolve.

The body of typical science today is still a mish-mash of jargon with some clever associations. Anyone posing as an intellectual celebrity has my distrust.

Yeah, it's volume versus diameter. The sun is 864600 miles across. The Moon is a little over 2159 miles across. Almost exactly 1/400th of the Sun diameter.

Now here's another one that's interesting: The Earth diameter is 7926 miles across. The Moon diameter is 0.273 of the Earth's diameter.

So what? Well, it takes 27.3 days for the Moon to go around the Earth.

Well, again so what? :) That only matters in a base 10 number system. Why might a base 10 number system matter? Well, the Earth is basically a planet with water on its surface. The triple point of water is 273.15 degrees Kelvin. The cosmic background is 2.73 K. Water melts at a temperature exactly 100 times warmer than the universal background radiation temperature. The number 100 is built into that. And here we have the Moon taking 100 times its fraction of the Earth diameter in days to move around the Earth.

Think anyone set that up? Or did the Moon just splash out of the Earth in a nice coincidence like that?

It gets better. The Moon/Sun/Earth system is related largely by four numbers: 2.73, 100, pi (3.1415 - ratio of circle diameter to its circumference), and the sides of the square (4). Four simple universal constants. Seemingly engineered into our local astronomy.

To see this again: there are 366 days in a calendar year, rounding up because it's a little more than 365. What's 100/366? Guess what: 0.273 again.

So what? Well, here's another one to relate it back to where we started:

Take the Earth diameter x 4 x 27.3 = 7926 x 109.3 = 866311 miles. Where did we see that number before? It's almost exactly the sun diameter (within 0.1 percent). The sun being a bit unstable, it might be accurate many times.

And one for the road:

Take the sun diameter x 4 x 27.3 = 864600 miles * 109.3 = 94.5 million miles

That's the distance from the Earth to the Sun at aphelion!

But it's all just coincidence. ;)

Yes it is all about diameter to a focal point - just high school trigonometry

Becoming as proficient in all sciences will likely be very helpful for self sovereignty and discernment. We do have AI as personal tutor now, so keep thinking and re-thinking and then think again. I feel that the psychic attacks might be more real than we think and thus self mental sovereignty and discernment is key. Be a mental Ninja!