You're asking about stealth, but lets describe it easy.

Think about radar cross section like this: I put on a blind fold and I throw a ball forward. If it hits anything, it bounces back, so I know there is at least something there. If I throw it and it doesn't come back, I can assume there is nothing there. thats how radar works, but with radio waves, not a ball.

The radar cross section, is basically like if there was a moving target when I throw the ball. Except instead of one ball, I throw like a hundred. With a hundred balls, I can hit it easily if its big, but lets say its super tiny, like the size of a bee, its gonna be way hard to hit, so I may never even know its there.

Ok, but even those hundred balls, eventually I will know its there, say 1 in every 1000 balls hits it but its gonna be really hard to figure out where its going and whats happening when only 1/1000 balls hit it.

There was a NOVA episode just a few weeks ago that demonstrated exactly how people could do this with very simple tools! (Like, stick in the ground simple.)

The records they were sharing and recreating were from the last 1,000 years, but it's not appreciably different from what Eratosthenes did, and what we assume older calendar-making societies did. And they demonstrated so beautifully exactly how it works, A+++ go watch the show and then plant your own stick in the ground to measure sun things!

Radar bounces a signal off flying things and then reads the blip caused by it. Normal planes show up as large blips, they reflect a lot. Stealth aircraft use materials and angles to reduce what goes back to the radar making it look smaller. Like the f22 apparently looks like a small bird so most radar technitions won't notice that since there are many small things.

Huh?

To be clear the following does not contradict u/Caucasiafro's explanation but compliments it.

From here:

> In the mouth itself, though, food scientists continue to discover new receptors and new pathways for gustatory impressions to reach our brain. Here are some taste sensations vying for a place at the table as a sixth basic taste.

> 1. Calcium

> 2. Kokumi

> 3. Piquance

> 4. Coolness

> 5. Metallicity

> 6. Fat

> 7. Carbon Dioxide

Note that article goes into detail about the arguments for and against clasifying those items as distinct senses of taste.

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Looking at a photo of the sun is different than looking at something bright haha

A year of 365 days plus a leap day every four years is actually the Julian calendar. The Gregorian calendar adds an extra rule: there is no leap day on years divisible by 100 unless it's also divisible by 400.

They knew what was relevant to them. More personal experience kind of knowledge than book larnin’. When your livelihood depends on finding edible plants and tracking animals to hunt you het pretty good at recognizing patterns in the weather and seasons. I might be able to say that there are just under 365.25 days in a solar year. A hunter gatherer will know that when the rains stop you have only a few days to move camp to where the herd likes to come through. But harvest as many of the funny blue berries as you can before you leave because they’ll be gone before you come back.

A great example of this is how food doesn't taste the same when you have a cold.

> Just by watching the moon you can come up with 13 months of 28 day cycles, and that's 364 days.

Um... The lunar cycle is 29.3 days long.

They knew that a cycle of 365 days had passed. And this period of time was extremely consistent and repeatable. And they called that cycle a “year”. But they didn’t necessarily need to know what was causing the cycle.

They didn’t necessarily care about the rotation of the earth. They cared about how long until they should plant their crops again.

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Disclaimer, I don't know the exact answer to this, but a while back I did come across this fascinating BBC doc on the "origins" of modern breakfast, lunch, and dinner traditions, from a British perspective. Should apply at least partially to NA. Worth a watch: https://youtu.be/tQk7NjiMAY8

You, my friend, need to learn about Edward Bernays. The godfather of modern propaganda advertising.

Essentially - bacon producer hired him to boost flagging bacon sales. He got a bunch of doctors to say "eating bacon/eggs/bigger breakfast was GOOD". Publish study, write about it in newspaper. Voila. Doctor sez eat big breakfast with bacon and eggs -> people do it. (this was back when people trusted doctors).

All good info here so far. Also notable, unless you're easy on the throttle, turbocharged engines tend to wear quicker.

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And the ancients just assumed this meant that the earth had made a full rotation (or in their eyes, the sun had)? I mean why did they settle on that assumption? I am sure one could have made a dozen others.

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Gold ions could well be reduced and precipitate out in the liver or kidneys, building up. They could also exist as organic gold molecules in the body.

It looks like this isn't a super well-studied bit of chemistry.

You can just look at where on the horizon the sun rises/sets every day. On the first day of summer, the sun rises the furthest north in the northern hemisphere. So you just count the days until it rises that far in the north again.

Also, you can measure the highest point of the sun in the sky each day. If you have the same length stick or rock on the ground. On the first day of summer, at high noon, the shadow will be its shortest length of the whole year. So you can just count the days until the shadow is that short again.

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Algal bloom?

That's because our sense of taste is really closely tied to our sense of smell as well.

To the point that a lot of people, unless they have been specifically trained, might not even realize that the "taste" of something is largely from an aromatic compound they are actually smelling.

That said, if you somehow perfectly got the actual flavor compounds right, and got the aromatics just right you could almost make something that at least "tastes" like the real thing.

Except then there are also things like temperature and texture/mouth feel that affect it too. So a gummy that tastes exactly like a big mac isn't going to trick anyone. Because a big mac isn't just "Big Mac flavor" it's about how two all-beef patties, special sauce, lettuce, cheese, pickles and onions on a sesame seed bun feel in your mouth.