this post was submitted on 18 Oct 2024
930 points (95.7% liked)

memes

10417 readers
2279 users here now

Community rules

1. Be civilNo trolling, bigotry or other insulting / annoying behaviour

2. No politicsThis is non-politics community. For political memes please go to [email protected]

3. No recent repostsCheck for reposts when posting a meme, you can only repost after 1 month

4. No botsNo bots without the express approval of the mods or the admins

5. No Spam/AdsNo advertisements or spam. This is an instance rule and the only way to live.

Sister communities

founded 1 year ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 21 points 1 month ago (2 children)

Where did you learn that? Is that a real thing people are taught?

[–] [email protected] 58 points 1 month ago (2 children)

3 miles is roughly how far you can see to the horizon (before the curvature of the earth blocks your line of sight)

https://www.omnicalculator.com/physics/distance-to-horizon

[–] [email protected] 18 points 1 month ago (1 children)

I don't want to check miles, but it's pretty on point with what I remember, which is the horizon being 5km away for a 180cm (~6ft) tall person. (3 miles is close enough to 5km)

Getting even a few meters of something under you would drastically change how far you see.

[–] [email protected] 4 points 1 month ago (1 children)

A few extra meters wouldn't be too drastic. From the top of Everest the horizon is about 300km away.

[–] [email protected] 19 points 1 month ago (1 children)

1.8 meters sees ~4.8km. Standing on top of a car, on someone else's shoulders, at say, 5 meters, would give you eight kilometers.

Granted, not too drastic yeah. But like, if you have a tree, and climb it, and it's, say, 15 meters. Now you can see ~14 kilometers.

I'd say going from ~5 to ~14 by climbing a tree (or a mast of a ship) is pretty significant, but not drastic, I'd agree to that, yeah.

I wonder how much it was an advantage at sea, really. Like the scout at the top of your mast would be able to see the enemy ship from very far, while the enemies would technically be able to see only the mast of the ship that the scout is on, making it much harder to spot. I'm sure someone's written about it in tedious length. An upvote to anyone who finds me such texts.

[–] [email protected] 2 points 1 month ago (2 children)

Well, there's a reason old ships had people high up as scouts. These days we just use radar and gps

[–] [email protected] 3 points 1 month ago

I mean yes, that's obviously the purpose. I just wonder how effective it was, and would like to read about it.

[–] [email protected] 2 points 1 month ago

did you just not read the last paragraph??

[–] [email protected] 3 points 1 month ago (1 children)

Depends how high you are. On a tower you can see much further.

[–] [email protected] 4 points 1 month ago (2 children)

Depends on whether it’s a tall tower or a tiny tower.

[–] [email protected] 2 points 1 month ago (1 children)

It depends on the family drama. You might get pulled away before you can look

[–] [email protected] 0 points 1 month ago

Before you can look where? It turns out the damn tower doesn't even have windows! You can see nothing but walls and your stupid boomer mom screaming you're a disappointment!

(Last week I had this, just not in a windowless tower. Fucking boomers)

[–] [email protected] 4 points 1 month ago (1 children)

Just googled it now, and I'm seeing the "3 miles" number thrown around a lot.

https://science.howstuffworks.com/question198.htm

[–] [email protected] 6 points 1 month ago* (last edited 1 month ago) (1 children)

That's just weird. The question is about the eye. And the primary "answer" they give is about the geometry of our planet.

Edit: At least the real answer is somewhere further down in the text:

Theoretically, in a vacuum there's no limit to how far away your eyes could see since light rays can travel an infinite distance, McCulley says.

[–] [email protected] 4 points 1 month ago

Light emitted farther than 46 billion light years away will never reach you. While traveling an infinite distance the universe expands faster, and light emitted not that far will get so red-shifted that it won't be visible anymore.