Once a Millennium Alignment of All Three Norths
ฝัง
- เผยแพร่เมื่อ 18 ธ.ค. 2022
- Own the map! www.ebay.co.uk/itm/364113096218
Get your North by North-North tour merch here! standupmaths.teemill.com/coll...
Thanks to Bec Hill for voicing the Norths Tour. I have a podcast with Bec and we talked about me making this video in the latest episode: aproblemsquared.libsyn.com/49...
If you're anywhere near Worth Matravers in Dorset you should absolutely visit The Square and Compass. www.squareandcompasspub.co.uk/
Here is the OS Maps post about the triple alignment. www.ordnancesurvey.co.uk/news...
However, if you watch their video be warned about when the diagonal line crosses the 2° line: their line slopes to the left and moves to the right, whereas my line slopes to the right and moves to the left. This is because the OS is drawing the zero-point for magnetic-vs-grid but I'm doing magnetic-vs-true. Which is a mirror image.
You can see all of NOAA's Historical Magnetic Declination data here: www.ncei.noaa.gov/maps/histor...
Huge thanks to my Patreon supporters who funded this ridiculous trip to the south coast of the UK to film a silly video. They also bought me two pints of beer and one packet of crisps. Which were all totally key props/research and not a mis-use of Patreon support funds. Support me and maybe next time I'll get a second packet of crisps. / standupmaths
Bonus thanks to Christopher James who put a link to the OS article about this in a maths communication whatsapp group with the message "I hope someone is planning to visit and make an interesting video about this." And thanks to Colin Beveridge who answered some key questions about it in that group.
CORRECTIONS
- None yet, let me know if you spot anything!
Filming and editing by Alex Genn-Bash
Written and performed by Matt Parker
Music by Howard Carter
Design by Simon Wright and Adam Robinson
MATT PARKER: Stand-up Mathematician
Website: standupmaths.com/
US book: www.penguinrandomhouse.com/bo...
UK book: mathsgear.co.uk/collections/b... - บันเทิง
Matt demonstrates that he has the special talent to unfold a map and then fold it back up correctly.
I can confirm that is a special talent indeed 😄
That’s a Parker square.
He is a god
It's all about remembering how you unfolded it, and undoing those moves.
That's a special skill?
The way matt crosses time and space is seamless.
Dude once repeated a piece to camera that started as a monologue, became a dialogue and ended up as a three way conversation . . . all by himself, and all three versions made perfect sense. It would not surprise me if he turned out to be a Timelord
@@stocktonjoans What video is that?
Wow, such differentiable
my bad, haven't seen it in a while and just re-watched it, it wasn't a three way conversation, it was a conversation with an infinite amount of Matts, like i said . . . Timelord
Anyone else think Matt is a Timelord?
"if you'll excuse me, I have a future self to go and become" is beautiful and is now how I will end all social interactions I ever have.
My social interactions usually end with, “Well, I could spend more time chatting with you all or I could leave. See ya.”
I can think of one hundred contexts in which that line would be perfect, each one with a different tone. Really, the outro of a maths video isn't close to that line's full potential.
I was not surprised that Matt had a spherical chalkboard as I assume he has a chalkboard of every geometric shape
"Every" is a lot - as in countably infinitely many if we limit ourselves to continuous shapes, I surmise. But a rhombic dodecahedral chalkboard he should surely have!
Oh they meant “every”. He has infinite chalkboarda
@@landsgevaer you mean uncountably infinitely many, right?
@@landsgevaer I imagine he also has at least one chalkboard net that folds up into a 3D object
@@ohmygoshitscole And he stores them in the rooms of his privately owned hilbert's Hotel.
If I know Past Past Matt, he already knew there was a pub with a mathematically funny name, and therefore felt 100% confident that Future Matt would be in such a pub.
How very cynical of you!
Are architects' tools as interpreted by Freemasons really mathematical?
@@wbfaulk Yes.
@@wbfaulk is architecture not an extremely mathematical field?
But he couldn't have been 100% certain of anything, mathematically, hence the uncertainty.
I can just imagine Matt trudging about on that windswept coast thinking "how the hell does Tom Scott do this every day?!"
4:00 "If you're ever in Dorset I highly recommend coming along". You really dropped the ball on that "endorse it" pun sitting right there.
Or to be more precise, he dropped the spherical chalkboard on it.
love it
It’s in the subtitles.
The pure indignation of "The magnetic south isn't even in Antarctica. Someone should look into that" just got me.
I was looking for this comment because I was thinking the same thing and saying to myself "Do you think"? He just totally dismisses it. I wonder what he will not say because I am sure that he has looked into it. As he said "it really bothers me". When something bothers you and you don't know, would not a scientist or scholar follow up on it?
Wait until you realise that the North Magnetic Pole, considered as a physical magnet, is technically the south pole (since opposites attract in magnetism and by convention of how field lines leave the north pole of a magnet and plunge into the south pole of a magnet) lol
Hmm, who was recently in a position to look in to things in the vicinity of Antarctica...
@@davidmccormick84 not that deep bro he was making a joke
Go ahead and follow up on it since you’re such a scholar :P
10/10 he stood up whilst performing maths
Matt really needs to add in a fourth north - celestial north. Now because the north pole doesn’t exactly point at the North Star, we need to add in a fourth dimension- time. I believe celestial north will line up with true north (and the other two north’s at exactly that spot) twice a day. So he needs to not only be there, but be there at the right time of day. Follow up video please :)
And if he brought the creator of "Dinosaur Comics" with him, then Ryan North would also converge on that spot. And if he wore the right brand of jacket, then The North Face would also be there.
Celestial north isn't identified with Polaris; it's the notional point in the sky around which all the (northern) stars rotate - and, obviously, always coincides with true north.
Perhaps if he could mention Processional North? This type of North is not itself a point but a line of latitude for which the north pole gradually drifts about over the 26,000 years of procession (this cycle actually explains why the Zodiac of 2000+ years ago doesn't align in the modern day and is roughly 28 days out).
Ahh, as a correction to my earlier comment, it is called the "North Ecliptic Pole" which would depend on the time of day for the observer as they are rotated by the Earth into it, at around 23.4° latitude.
en.wikipedia.org/wiki/Ecliptic_coordinate_system
@@timseguine2 l
99p99⁹p9⁹9p⁹⁹
It feels exactly like a Tom Scott video but with Matt, and i like it!
When Tom Scott said "I can't do this forever" some time ago, I guess Matt decided he'd take up the mantle of presenting interesting things.
when I saw the thumbnail I thought it was a Tom Scott video for a second until I read the channel name 🤣
I will admit I like Matt’s presentation style more. I’d love if he takes on these kinds of videos
I would enjoy seeing maths Matt and Tom Scott's friend Matt Grey get together; they could just geek out about something for ten minutes and it would be adorably wholesome.
Took me over half the video to realise that he was talking about the different *directions* north, rather than the different *points* north. I was so confused as to how on earth true north was that far south.
Exactly, threw me as well
I’m still wondering how he consolidated the true north (axis of rotation?) and the grid north. The axis wobbles as well.
@@billr3053 The axis wobble is less than 20 centimeters a year. I don't think that's worth compensating.
it's always nice to know that matt can bend spacetime to his will
hello comrade
Total aside: at a lab supply one can purchase cork rings made for holding round bottom glass flasks. Perfect for preventing spheres from rolling around.
Or if you get piles
If you're a sketchy garage chemist, you might just use a roll of tape. The leftover cardboard bit is *nearly* as good as those fancy cork rings.
@@ucantSQ I finally bought a ring stand to do it properly now. It is so much easier to hold my RBFs and other glassware, but I have to put bricks at the bottom to hold everything there.
@@ucantSQ Duct tape really is the answer to everything.
@@vigilantcosmicpenguin8721 Duct tape is not the answer to Russian aggression.
I’ve spent my whole life learning, loving, and teaching math and physics yet today is the first time I’ve ever seen, heard of, or even conceived of a spherical chalkboard. Love ya Matt. Love ya.
you can buy chalkboard paint and turn anything into a 'chalkboard'. My professor had a giant drafting table and part of it was painted with that stuff. But a spherical chalkboard is such a clever idea.
I will say Matt, is fantastic at timing his split screen/timeline selves for conversations with himself. Definite improvement over the years with all the future, past, matt2, occasionally matt3.. Quality stuff!
I always hate it when those two fight!
It's nice that he lets the guy who runs the "Matt_Parker_2" channel come on the main show time to time
He should probably figure out that he can slightly speed up or slow down the silent part of the video to nail the timing even better.
I'm less amazed by the future Matt, who can just pop in an earbud and put a screen nearby to react to past Matt. It's also not entirely magical when Matt 2 or Matt 3 just stand around and nod or smile while Matt 1 does the heavy lifting. But when past Matt times his bits just right like this one, it's some really good filmmaking. And when multiple Matts are squabbling, but then sync up just right, the editing must be like a three-body problem.
“It’s called the square and compass”
“In Dorset?”
“I do, it’s very good indeed”
My favorite aspect of this is that Matt came to the very south of the UK to talk about three norths being in the same direction for once
It took me a bit too long to remember that North is also a direction and not just a point. I was wondering how the North Pole(s) had managed to move down to Dorset.
that was me as well. I first thought he was somewhere in scotland, and thought even that was weirdly south for north magnetic pole. Then when he revealed that map and placed himself on the southern coast I was really confised.
Life is peaceful there
(Go North) In the open air
(Go North) Where the skies are blue
(Go North) This is what we're gonna do
You're 90 degrees off. Try turning left and rewriting the lyrics
Matt does look a bit like Neil, doesn’t he.
Pet shop boys
@@bernhardjordan9200 Village People
@Andrew Crews
I second this; everybody knows that It's Grim up North
In Polish language both "north" and "midnight" translate to "północ". So if you recorded this video in Polish and waited a few hours you could talk about alignment of four "północe"
And also, on an equinox as there are two different midnights: the normal one and when the antipode has solar noon!
Полночь)
@@user-vm1hi7bo5s Stop speaking Putin!
@@Anonymous-df8it Nah. Didn't mean that. I hate Putin actually, yet i'm still speaking the same language. Languages are ok, no matter who used them. Like, have you ever told Deutsch to stop speaking Hitler?
@@user-vm1hi7bo5s Thanks for the idea!
That pub was the absolute perfect setting for this. It's like someone built that pub in 1830 and said, someday, someone's going to choose this place as the warm, cozy location to film a maths video.
I am just wandering about all the other patrons looking at the weird guy with a spherical chalkboard
Exactly what the Masons and Templars want you to believe.
It's nice to see Matt getting along and cooperating with future Matt. Some youtubers I watch don't get along as well with their future selves.
"I like rambling!". You sure do Matt. And we listen to your rambling intently. ;)
This video is so perfectly nerdy! I totally love it.
I once taught surveying to hapless forestry undergrads, and the differences between the 'norths was the bit of slushyness that just irked the hell out of anyone studying this very precise and detailed skillset.
I would argue that grid north is not a real north. It is simply a product of how those specific maps are drawn whereas true and magnetic north are defined by the earth.
Still a fun video, thanks Matt.
So just to be sure I understand this correctly: what you call "grid north" is actually dependent on the map manifacturer? If you live in another Country there is another grid north (or possibly several if the Country is so large that the maps use different "grid norths" for different parts of the Country.
Yup, choose whatever map where the green line is passing through the center line, and there will be a similar point (assuming they used the same method for the grid).
Yes, "grid north" specifically refers to the UK grid - and Ordnance Survey is so intrinsic to our national mapping that I can't imagine anyone would have developed an alternative standard. Other countries may have their own official "grid north", or may not and it could be down to individual cartographers to decide how they want to handle it.
Indeed, the United States uses a multi-grid system for these purposes (or, actually, several--it's quite complicated).
I believe Grid North makes no sense (i.e. isn't a thing) if you are using to the standard Mercator projection of the globe, or Web Mercator used in, e.g., Google Maps. I recommend the Wikipedia article on Transverse Mercator to explain the whacky local versions of Mercator projections in ordinance maps.
USGS topographic maps aren't rectangles, they are quadrangles. The northern edge is slightly smaller than the Southern edge, and the corners aren't 90°. It's probably not perfect but all grid lines align with true north.
My town's nearby square is almost a sort of compass. There are streets coming off of it, named after the cardinal directions (except south, 'cause there's water), that _kind of_ align with north, east, and west (I live on the 'west' street). It was built centuries ago, so it's not quite exact, but still pretty cool. Now you got me wondering exactly how much off they are. I do know that the square+streets are rotated somewhat counter-clockwise compared to what they should be.
Look at the City of Adelaide
It's a fairly common arrangement. Most of the time the town grid is rotated to roughly follow that local shoreline since that makes planning easier.
@@rianfelis3156 Yah, many towns have their streets aligned with a local river or other body of water. Others are aligned with roads or (especially) railroads.
And sometimes surveyors got lazy and used (then-)magnetic north instead of true north. Or they made errors that left the grid lines out-of-square.
And sometimes their compasses got deflected by iron deposits in the ground, before the area had been mapped in enough detail to correct for it. Hibbing, Minnesota, US is in the Mesabi Iron Range, and the Public Land Survey grid's section lines get particularly wonky around there. Much of Hibbing's street grid is aligned with the wonky section lines instead of true north -- as are a lot of property lines outside the built-up areas.
We don't even have a grid. Okay, at least not ouside the areas that had to be rebuild after the war.
@@michaelenquist3728 And the Denny Triangle.
I think my favourite slang expression from the UK has to be "all over the shop". Really versatile for giving the impression of things being either abundantly available or universally screwed up.
Had to watch the video to understand what was meant by the title; I thought he meant the poles were aligning in the UK somewhere. Even if the magnetic pole wandered that far, the other two poles physically can't get to the UK.
I love his quirky humor and these time bending bits are so good.
Fun fact: for some quick and dirty navigational math, you can use the cosine of your latitude as a scaling factor for how far east or west the same number of degrees will take you. for example, if you are at the equator and you walk 1 minute west, you will have walked about 1852 meters. If you are at 60 degrees north, and you walk 1 minute west, you will have walked about 926 meters (which is cos(60 degrees) * 1852).
You can also work the math backwards to figure out how many meters you need to walk to get the desired longitude. for example, if you are at 45 degrees north and you want to walk 1 minute to the east or west, you must walk about 1309 meters.
In other words, you can use the cosine of your latitude to tell you the value of an arcminute of longitude. I use arcminutes because a nautical mile is 1852 meters or 1 arc minute of longitude at the equator (roughly)
Why is it "quick and dirty"? Is it wrong or inaccurate?
@@NeatNit For one it assumes a perfect sphere
@@NeatNit Yah. I would think that the "quick and dirty" method would use an approximation of cosine that you could do without trig functions. :)
The one shorthand I use is to find south depending on the time via a watch. At noon the hour hand, the sun, and south should align. The sun moves 15° per hour and the hour hand on the watch moves 30°, so the sun should be right in the middle between the hour hand and the 12 o'clock position at south
Something uncanny about stand-up math doing walk-around cartography and sit-still physics
around*
@@Anvilshock thank you for the correction
@@feedbackzaloop thank you for correcting
"walk-around cartography" is actually a decent channel name
@@feedbackzaloop Thank you guys for thanking each other
This really should be a Matt + Tom Scott collab.
Also @4:00, "a wide range of crisps, chips if you're American", talking about fries.
I caught this too, then second-guessed my understanding. As such, your comment has inadvertently resolved my uncertainty.
A pub named square and compass with logs? Count me in!
I will point out that grid North is a UK thing, as it depends on the definition of the UK National Grid.
Other countries' mapping systems have different grids, and when their grid Norths line up with the other two is a matter for their mapping geeks
There are multiple such lines in the USA, and the line of zero magnetic declination is currently crossing one of them in northern Iowa. The intersection point is moving south at the moment.
Not to be confused with The National Grid, which is our national electricity distribution system and also the name of the organisation that maintains it.
@@jameswalker199 not indeed!
Also not to be confused with our rather less known National Grid for gas, owned by the same company 😉
In Finland the military uses 27th longitude as the central line. Civilian maps use three different zones. 24rd,. 27th and 30th IIRC - though we call it the map north and the true north is called the polar north. A singe zone works on countries like Britain and Finland that are rather narrow east to west. On wider countries it would work poorly. Though I went to te army in the 80s so it can have changed since that.
if there was a BBC logo in the top corner- I wouldn't even doubt it. Very well presented.
Can we give a shout out to the cameraman who put up with the same crappy weather but with none of the glory.
11:08 "Please, flat models?"
Ah, I see you are a man of culture as well
There's one true north, and one magnetic north, and a different grid north for each projection used.
And there are hundreds of different projections used.
So the earth is in need of a psychiatrist...
You maybe should have taken a nautical map with you. They have little markings on them about how much to correct the magnetic north to become true north. Also they have a ±x marking to add/substract every subsequent year after the map was issued to correct for drift
I had a couple of OS maps next to me while watching this video so just checked and this info is in a technical information section, including the date for the magnetic north measurement and estimated ± for annual change.
You can see on a lot of small airplanes that where the "backup" magnetic compass is, there is a small chart with some "error correction"
I've watched you and your channel for a decade, Matt. That's >60% of my life. Thank you for sticking to it in the long haul.
So you've been watching since you were 6/7?
@@Queenside_Rook It'd be 5 or 6 actually, assuming he truncated the percentage to the nearest multiple of 10 percent
@@SilverLining1 The equation to solve is 10 years > 0.6L, where L is his life.
@@backwashjoe7864 , which is why 6 is the oldest OP could've started watching the videos for the statement to be true. Ten years is exactly 60% of sixteen and two thirds years. Because we count ages in integers, ten years being greater than 60% of their life means they are, at most, 16 years old (ten years is obviously greater than 60% at younger ages as well). Subtracting the ten years gives 6 as the oldest age to start.
@@SgtSupaman oh right! Sorry, had a brain burp on that one. :)
The Square and Compass at Worth Matravers - great pub, good ales and they host some excellent local bands and musicians. What's not to like?
"Get a shiny rock, with some other properties... Let it suspend..." - Why do I feel like this is how Matt proposed to his wife?
Another interesting video. The OS grid definition of north is specific to the UK, but other maps have the same problem. In the USA, the US Geological Survey uses UTM grids, but as the country is large, there are several UTM zones. This means you have a different grid north when you cross the zone boundaries.
And the line of zero magnetic declination is crossing the middle of one of the zones at the moment!
Great video Matt, thank you! I help run the D of E at the school I work at and always struggled to explain to the kids the difference between the three Norths. This video is now going to be compulsory viewing for them.
"I have a future me to go become" sounds so deep for an off hand remark.
I love how you so seamlessly intertwined the two places in spacetime and even did interactions between them. I don't think I could pull that off!
When I first learned about the UK "Right to Roam" my mind was blown as a USA person. Let's not overlook that detail here 😁
Mind blown? Like, how blown? Like, 12-gauge?
Bill Bryson's book 'Walk in the Woods' is in the spirit of your comment here!
@@Anvilshock There are parts in the US where you might just get met with a 12 gauge if you go wondering around on private property. I don't know about the rest of the world, but in the US, people are really serious about "their property" and whether anyone can be on it. At least the US has the good sense to not allow private beaches, for the most part. I think all the good beaches are public even if there is a 40 million dollar house on it.
@@Anvilshock How blown? Fully. Fully blown. The idea that you can walk (most) anywhere in the UK including private land is an utterly foreign concept in this country (which is 100% stolen land, but I digress).
England doesn't really have Right to Roam. Most private land and farmland (that is almost all land) is restricted access except where long standing footpaths cross it.
In Scotland there are far fewer restrictions and, as long as you behave yourself and follow some basic rules, there aren't many places you can't go, and even camp overnight.
I so want to walk that line now! I knew about declination (and deviation and variance) from learning navigation in flight school, but I don't recall hearing about grid north ... or I've forgotten. I'm looking at one of my dad's old navigation charts and the longitudinal lines aren't parallel. This chart uses conic projection so great circle routes are straight lines, which might be true for aviation charts generally. Thanks for stretching my grey matter.
The grid was a big deal on land. Ordnance Survey maps were made first for the British Army, then hikers found they were great.
Fun fact: the 0 degree 0 degree coordinate point, i. e. the north pole is actually about 1.5 m away from the point where the Earth‘s rotation axis is. So there are technically two north poles.
I was wondering if he was going to mention this. But since the video was at the level of just the first 3 Norths, and the wobble of the earth and other spinning objects is taught in upper division physics, I didn't really expect to see it. Maybe your comment will encourage some student to learn about it.
What's the difference between the north pole and the earths rotation axis point? Also is that 1.5 meters or miles?
@@brandonjslea1562 OK, get a top or something like it. You can imagine that it would spin exactly around the rotation axis. But when you spin it, it will wobble for several reasons. That wobble is around the rotation axis if it wasn't wobbling but spinning true. But the top is still spinning, but not around the true rotation axis.
There are many fascinating demonstrations that make no sense until you can see the math behind it all. But I'm retired and don't have access to a physics stockroom to even make videos of it.
Let search for one on youtube.
@@brandonjslea1562 north pole is 90N latitude, rotation point moves relative to that. L/L grid isn't defined by the rotation or your house coordinates would change all the time
Only two? Sure.
The Square and Compass.
In Dorset?
Course I do, I bloody love the place!
Yeah, I think the two sentences "In Dorset" and "highly recommended" are said next to each other just to troll us folks with a highly sensitive gag reflex.
Amazing video Matt! Honestly these video are so entertaining and educational. Keep up the good work!
Sir (pending) Crispin Farquhart is still circumnavigating the 53rd parallel in search of the East pole. We wish him well and good speed ;)
“Sir (pending)” is somehow both tryhard and a power move.
Mind Blown! North 1 & 2 I knew about, but North 3, I just didn't know that detail until this video - thanks Matt, that was great, and just the kind of place and time I'd go and find just to "be there"
I've never properly understood the differences between all three. Thank you, Matt, for making that clear and simple to follow.
Matt loves to ramble.........and does so entertainingly every video!
I think this video went in the right direction. Great job.
Great explanation of this subject. I once tried to teach some people I was taking on a backpacking trip the difference between the three, and we were doing well right up to the point I threw in the magnetic N to grid N deflection, and how one must take this into account when shooting an azimuth and in using techniques such as modified resection. I shoulda just been happy with my success with the three Norths.
Matt can talk so well between the past and future, I’m convinced it isn’t an editing trick and he really can speak through time.
I was expecting the third pole to be the geomagnetic pole, hadn't even heard of grid north
I have a minor in geography and took three map making/reading/interpreting courses. I don't recall the term "grid north." I guess any map can have its own particular grid north, chosen arbitrarily, so it's not really a thing.
@@ronm3245 Matt is British, so everything is a thing. (mad men and englishmen)
There are maps that show how to adjust for the local magnetic field for small plane pilots.
Great video as always.
That map of the magentic declination is truly terrifying. Especially as a flat projetion.
"I have a future me to go and become." Deep!
The mat who walked up a hill and came down a pole.
Thank you Matt for once again solving the math problems
Thank you math for once again solving the Matt problems
@@zimi5881 oh no, it's gonna take more than math for that...
@@willsterjohnson Parker Math?
I love to see the softening edges develop on future Matt after a pint at the Square & Compass. Great job!
Fact: this video is in real time. There is no cuts or edits, he actually is transporting himself across reality just so he can teach us some sweet maths
I expect Matt's head globes to be on sale very soon
He should have spun so we could see the axis of rotation.
That would be terrifying.
The Parker Sphere
Not sure if I prefer Past Matt, Present Matt or Matt's Yet to Come
It’s always a pleasure to see a new video. Been following a long time and the quirkiness is always finished by the video awesomeness
Congrats on 1 mill subz! Well deserved.
Did you say the line leaves the UK where it enters Scotland? 😂
edit: Hm, rewinding a few times I think I understand now, that "leaving the UK" referred to going over the ocean. Listening this on the fly it sounded quite different. ;)
I wasn't surprised that Matt had a spherical blackboard. I am surprised Matt doesn't have one and had to borrow it. I am also surprised that someone who is not Matt has one!
To be fair, it's his wife's, which makes it almost the same.
Today I learned Matt's wife is a physicist & I'm emphatically okay with that.
- I had some beer and crisps at the Square and Compass in Worth Matravers.
- In Dorset?
- I certainly do, yes.
Matt Parker: I love rambling.
Viewers: we know, Matt, we watch your videos.
😄
14:30 As an American I'm like 90% sure you made most of those places up.
excuse me, can you mispronounce Frome for me?
@@NoNameAtAll2 Portsmouth.
@@NoNameAtAll2 Worcestershire
Once in a lifetime event, sadly a little bit excited for this as an outdoorsman 😂
From now on, I'm nicknaming 2022 the Year of Coincidences. First there's Two's Day Tuesday, then there's this, and now also the alignment of the planets and moon over the next few days.
That pub was so perfect, it seemed like a set...but then I remember I have been to a pub in England and they are kinda like that.
So, to clarify, while discussing the green line, he means that the _line_ doesn't point in the right direction, but that magnetic readings asking that line would point in the right direction, right?
The green line shows the places where magnetic north points to true north
Yes, that's exactly it.
In other words, if you were at the magic N×NN point and followed your compass heading north, you would start out heading true north and would then deviate from that direction and follow a curve.
Alright, thanks folks. His pronoun usage was a bit confusing to me.
One day I would like to visit the UK and do a proper ramble.
I wrote a mapping app for the phone and the conversion from GPS to mercator geometry maps and Ordinance Survey grids is astonishingly complex. And it's not even precise - there's iteration involved and you need to specify the accuracy you desire.
"Time is an illusion, lunchtime, doubly so." How he would love Matt!
Dear Matt Parker,
Recently you held the collatz collab. I did participate, however my teacher was unable to send it sadly. I gave it in,however have never seen it again. I am in year 9 and would like to inform you of my apologies for not being able to send it in.
From Sanaa
P.s I really enjoyed this video, you and many TH-camrs on numberphile have inspired me to pursue a career in maths, thank you.
The US has a grid north too and it causes a lot of strife for me. My home state is far to the east of that line, and one of it's borders is defined by a line of longitude. But on a lot of merchandise and posters and signs and whatnot, people have the orientation of the state cropped out of the US grid north. Rather than with the state specific grid north. Or you know, aligning that border North-South. Because of the size of the US, the difference is 30 degrees or so, so it's not like I'm being nit picky. This is a huge tilt of the state being off kilter.
Why didn't the map manufacturers make the maps curved slightly to compensate?
which state?
@@stevevernon1978 Solid
/j
my favourite film from Alfred Parker: North by NorthNorth!
"Once you compensate for that correction..." Could speak volumes about humanity if taken out of context.
So, would we then consider magnetic north the Parker North of the set?
what projection did you use to map the noah magnetic chart onto a sphere? because as i understand it, most common projections onto a sphere get pretty wonky around the poles.
Since it was already a projection from the sphere to a plane, he just reversed it. Like a reverse mercator, for example.
Well, generally, a 2d map is a projection of a 3d sphere onto a 2d surface. The inverse function is always a thing (if it's not one of those maps that just kinda cuts out sections - generally, sections entirely made of ocean and/or disliked countries - to make it all fit with minimal distortion). If it's one of the projections that captures all the data but distorts it, one can always, always cleanly map it back to the original surface in a distortion-free way.
"The Earth is a sloshy mess." Parking that one right next to, "Time is a weird soup."
[I'm going to preface this with the hope that I've remembered everything correctly.] Pilots around the world use magnetic north for navigation, and the charts that they use include the correction for true north. Because the magnetic north pole -- currently located somewhere in Canada's north -- is constantly moving, these charts have to be updated from time to time. Unless you're in Canada. The magnetic north pole moves around enough, and is close enough to Canadian airports, that Transport Canada would have to update their charts constantly, so instead they use true north.
So this only applies to UK people?
I get the true north and the magnetic north and how it's cool when they align. But "grid north" is basically just what a random map company in the UK picked as north? What if I have a different map?
A "random map company"? Good grief, this is (organ chord) The Ordnance Survey! We live by it here in Britain, it is an institution as beloved as the BBC or the Monarchy! The choice of the 2 degrees west line of longitude as grid north is rational and explained in the video.
In aeronautical charts (maps), they leave the pie shape in place, so every square is actually a trapezoid
The joy of discovering my home town is one of those this will pass through. Honestly, it must be the best thing to happen to the place this side of the millennium at least...
Square and compass? That’s a freemason pub bud
I noticed that too. Hmm... wonder if it was intensional 😂
Kind of recognised by the coastal geology near Winspit , confirmed by one of the busiest pubs in England in summer at Worth Matravers . Tilly Whim and that whole area at St .Aldhelms Head coastal pathway is great country to explore .
Love the reference to the intermediate value theorem.
Awesome to see your production values improving. I learned of you through numberphile. Maths are awesome too, but practical applications are always my favorite. Thanks dude