Eli5 why there are more lines of Longitude then Latitude
In: 35
The historical reason is that way back in the day the math & science heavy civilizations in the Middle East decided a circle would have 360 degrees.
If you hold out your hand, palm facing you, you count with your thumb against each segment of each long finger and (if you have all four fingers in their normal arrangement) you end up counting 12. Raise a finger on the opposite hand and start another 12. By the time you count all five fingers on the opposite hand, you have 60.
For reasons that are probably more mystical than scientific, they took six 60s to be special (eg. days in a year are nearly that)…anyway, long story short there are 60 minutes in an hour, and 60 seconds to a minute.
We have 360 each of longitude and latitude, but North/South they are broken up into 90s and East/West into 180s. But of the former four quarters add to 360 and in the latter to hemis add to 360. The *label* changes but the *number* does not.
As the Earth rotates, local noon follows the Sun at the rate of fifteen degrees of arc per hour (24×15=360). The relationship from there to longitude gets more complicated, has linguistic and real-world relationships but not 1:1, and is NOT something I have an ELI5 ready for but they are related. If you have a good enough clock, a way to determine noon (eg. a shadow you can trace) and a timetable of true local noon for a bunch of locations, you can work out how many circular degrees you are offset from any of those locations with just a little math, and by little I mean some high school geometery and trigonometery.
The sun appears to move by one degree of arc (of the 360) every four minutes, or 15 degrees of arc per hour (see above). That is, if you and I are separated by one degree of longitude, you will see shadows strike local noon four minutes earlier than I do. If we are separated by 105 degrees of arc, the difference is 105 degrees / four-sixtieths (also known as 15). 105/15 = 7. My time zone is GMT -7; when I get home at midnight local time I can listen to London breakfast news live because it is 7am in London (105 degrees or 15 degrees x 7 hours) to my east. And, indeed, the 105th Meridian runs through my city and is marked by a metal line crossing the plaza through our train station, [like this](https://ducdn.denverurbanism.com/wp-content/uploads/2015/12/18145643/2015-12-29_105th-meridian-plaza-400×600.jpg) which is exactly that 105 degrees of arc (420 minutes of time) from [this similar 0 line](https://th.bing.com/th/id/R.e11758ade66a1d870d6162946802e7f3?rik=iZAFilnMDMbgTQ&riu=http%3a%2f%2flh3.ggpht.com%2f-HAsRiY6z9qE%2fVJL1PBGstoI%2fAAAAAAAA934%2fI1lLPuZdUEA%2fprime-meridian-3%2525255B6%2525255D.jpg%3fimgmax%3d800&ehk=jxq9fPEBxrG52XeVAOZ0rC8XU3SnzT7qzG1tA4kgRTU%3d&risl=&pid=ImgRaw&r=0) in the Royal Observatory in Greenwhich, England.
Anyway, I digress, point is there are direct relationships between minutes of arc and minutes of time but this is not a geometery ELI5, I just thought it was a neat tie-in to history from civilizations that occupied Earth so long ago that the mammoth were around and the pyramids were not a thing…yet we still bear homage to their ingenuity and math/science breakthroughs in our modern efforts to measure the Earth and understand the universe.
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