Submitted by Anonymous on Mon, 12/14/2009 - 14:03

Dear Mr. O'Hara,
We've been studying magnetism in fifth grade. We want to know what will happen if you bring a compass to the South Pole. We think the needle will rotate 360 degrees multiple times because when you are at the South Pole you can go any direction and still be going north.

Sincerely,
Mrs. LeBlanc's Fifth Grade Class
East Valley Elementary School
Fernley, Nevada

Casey OHara

Hello to Mrs. LeBlanc's class!  This is a great question, because magnets are so much fun.
Two things that you might want to know: first off, there are actually two south poles - the "geographic" south pole, which is the axis of the earth - if you stood on this for a whole day, you'd spin in place like the middle of a merry-go-round.  There is also the "magnetic" south pole, which is where the magnetic field lines of the Earth's magnetic field point inward, and the back end of a compass needle points towards this one.  (there is also a geographic north pole, where Santa lives of course, and a magnetic north pole, where compasses point).
Just to make things extra confusing, the geographic south pole and magnetic south pole are not in the same place!  (same with geographic north and magnetic north!)  I bet you can look online to find a map of exactly where the magnetic north and south poles are, and I bet you'd be surprised at how far they are away from each other!  Also on many high-quality maps, look at the little compass that shows you which direction is north (point towards the geographic north pole).  There might also be a second arrow, not quite pointing in the same direction - that is pointing at the magnetic north pole, which is not quite in the same place.
But what this means for your question is that if I had a compass here at the geographic south pole, the back part of the needle would point in the direction of the magnetic south pole, and the front part of the needle will point towards the magnetic north pole. Even if I spin around, the needle will always stay pointed in the same direction.
Another cool thing is that at the magnetic north and south poles, the magnetic field lines actually point up and down, rather than along the surface.  So really, if you stood on the magnetic  south pole, your compass would try to point upwards! (or downwards, if you stood on the magnetic north pole).  They make special compasses that can point in the up/down angle of the magnetic fields, as well as parallel to the earth's surface.
Have fun, and enjoy studying magnets!
--Mr. O'Hara

Guest

Dear Mr. O'Hara,
Thank you for the interesting facts about the geographic and magnetic poles! We were surprised to learn that a compass would actually try to point up at the magnetic south pole!
Mrs. LeBlanc's class

Lilly Bosworth

Hello Mr. O'Hara!!!
I am a part of Mrs. LeBlanc's class. I was wondering; so you're telling me there's two North Poles and South Poles?!! Crazy!!! What if you had a cheap compass that isn't very good. Would it change your results? If so, why? Oh, and how do you access a computer where you are? Wouldn't it freeze?
Thank you Mr. O'Hara!!!
-Lilly Bosworth
Mrs. LeBlanc's fifth grade class
Fernley, Nevada 89408
East Valley Elementary School

Kirsten

Dear Mr.O'Hara,
I'm part of Mrs.LeBlanc's class and I was wondering,what do you have to have to go to the North Pole or the South Pole?Thanks for the information on magnets!
From
Kirsten
Mrs.LeBlanc's 5th grade class
Fernley,Nevada 89408
East Valley Elementery School

Casey OHara

Hi Lilly,
great questions!  Yes, there are two north poles and two south poles.  The earth rotates around the geographic poles (just like on your globe) and the magnetic poles are where the compass points.  Did you get a chance to find out where the magnetic poles are?  Maybe you can get a globe, and put stickers on it where the magnetic north and magnetic south poles are, just to see the difference!
A cheap compass might act differently, just because it could stick from friction.  Any time you are doing an experiment in science, you'd like to use the best equipment you can, because bad equipment can give you bad results!  For the IceCube project, each of those light sensors we use costs about $5000 (and we're using thousands of those, so just those by themselves cost many millions of dollars) because we want to get the best data we can.  I guess in 5th grade, your teacher doesn't have millions of dollars to spend.  But you can still make a pretty good compass with cheap materials.  Try this: take a sewing needle or pin, and a strong magnet, and rub the magnet on the needle, always sliding the magnet towards the point.  Do that a bunch of times (maybe 20, or even a hundred, more is better), and then take small pieces of cork.  Stick the cork on both ends (don't stab yourself - I did that, not much fun!), and float it in a little tray of water (a glass or ceramic bowl - NOT metal! or ask your teacher for a petri dish, those work well!). Floating it on water allows the ends to move around easily.  As long as the pin stays in the middle of the dish, you should see it turn so one end points north and the other end points south!  That's a compass right there.
And as for computers - they would definitely have a hard time working outside!  The cold causes lots of problems with batteries, including cameras, walkie talkies, and car or snowmobile batteries.  The chemical reactions inside the batteries slow down with low temperature so they don't last very long.  But I use my computer inside, so it stays nice and warm without any problems.
--Mr. O'Hara

Casey OHara

Hi Kirsten,
I'm not sure exactly what your question is asking, maybe you can clarify.  Do you mean what equipment do we have to have for the cold? Or something else?
The equipment we need to survive in the cold is lots of thick clothing!  For the South Pole, we fly to New Zealand first, and go the the Clothing Distribution Center (CDC) where they supply us with: thick warm boots called "bunny boots", nice thick warm socks and gloves, extra sets of long underwear,  some overalls like you wear for skiiing, and a big red parka stuffed with goose down.  They also give us some head protection to keep our heads nice and warm, and ski goggles to protect our eyes from the sun and the wind. Once we have all our clothing, we get back on a plane which takes us to McMurdo Station in Antarctica, and finally another plane that takes us the rest of the way to the South Pole.
When we are working outside and it's way below zero, if we are wearing all the right clothing, we don't even get cold.  The only problem I had was that my fingers would get cold sometimes, so I used some of those hand warmers you can find at ski shops, and stuck those in my pockets - so when my fingers got cold I could warm them up quickly!
I am not sure for the North Pole, but I bet they use similar clothing.  Some of the other expeditions this year went far north, so maybe you can ask them a question on their journals! I hope this answers your question, thanks for reading my journals!
--Mr. O'Hara

kirsten

I ment what do you have to have to qualify to go to the North Pole or the South Pole?

Casey OHara

Oh, that's a good question!  I can't vouch for the North Pole, but I met all kinds of people at the South Pole with all kinds of qualifications.  There were all the scientists doing research of course, most of them were in graduate school studying some aspect of science.  But there were also technicians who make all the equipment work, carpenters, painters, electricians, and such.  There are also people trained to work in the kitchen, run the communications, and to fly the planes, drive the snow machines, and keep everything clean and tidy. 
And there were plenty of people who just are willing to work hard and applied for a job at the South Pole, and were lucky to be hired to help out in all kinds of ways!  I think most of the "GAs" - I think it stands for General Assistant - had a college degree but not necessarily anything related to the South Pole.
One qualification we all have to go through is called "physical qualification" or PQ - which means a thorough doctor's and dentist's exam to make sure we are in good health.  They don't want us to get really sick or injured while we are down there!  And for the people who are staying for the whole winter (nine months, with no breaks - no planes coming in or going out, even in an emergency!) they make sure they are mentally prepared for the challenge too.
 

kirsten

Thanks! Merry Christmas!

Lilly Bosworth

Thanks as well!!! To Kirsten: Hi!!!

Anonymous

hi Mr OHara,
Thankyou for the imformation that you sent out . I am or NZ and in school I am researching the question"What happens to a compass wen it is at the south pole?"
Your information has come in very handy for me. Thankyou.

Anonymous

Dear Mr. O'Hara,We've been studying magnetism in the 4th grade gateway. I just wanted to know what
direction will a magnet point if you were standing on the north pole, south pole, or the
Equater. Thank you Mr. O'Hara.
Sincerely,
Sydney Mrs. Norton's 4th Grade Class
Mather Hieghts Elementary School
Rancho Cordova, California

Anonymous

Appropriate since it's the centennial of Amundsen's arrival...First, how did Amundsen know he'd reached the south pole? As you describe, the magnetic pole is far away so a magnetic compass wouldn't help. I looked up gyro compass but it doesn't seem to imply it was used to navigate to either pole (doesn't mention being used by Peary, Scott or Amundsen) and it was a fairly new gadget in 1911, by the sound of it. And Scott must have used the same method or trusted that Amundsen's flag was on the right spot.
Second, by what "time zone" (they had been in use for a couple of decades by 1911) did Amundsen run his expedition? New Zealand time? December 14 by his time, but still December 13 by the western hemisphere time zones.
Third, how did these early explorers navigate back out to the coast without getting lost? I'd expect the wind to obscure their footprints, so did they leave sticks in the ice every few miles and watch for them? Are there distinctive landmarks... or is the mountain range they crossed visible at the pole?

Tony

Very good questions left unanswered since 2011. Someone who has the answers really ought to post them for us temporally misaligned visitors (It's July 2015)

Janet Warburton

Hi Tony. Sometimes, they miss the questions and never get a chance to reply. So, I will forward this question to the teacher and see if he can reply.
Thanks for following along!
Janet

Casey O'Hara

Hi Tony, thanks for the comment - I haven't been receiving notifications on these, so I never realized people were still asking questions. I'll do my best to answer them, thanks!There are a few other friends of mine who have also done expeditions to South Pole Station, so perhaps you will find other interesting questions (and answers) on their PolarTREC pages!

Casey O'Hara

Hi Sydney, I suppose you are now in the eighth grade, sorry for the delay in responding!If you still want to know... a "regular" compass usually constrains the needle to lie flat, so it can only point along the surface of the earth. If you could find a 3-d compass, you'd get more interesting results near the poles!
The needle of a compass aligns itself along magnetic field lines (of the Earth, if there are no other nearby magnetic objects). You can envision the magnetic field lines of the Earth as lines sprouting out of the magnetic north pole, and extending around the planet, then plunging back in at the magnetic south pole. If you read the earlier question, you already know that the magnetic poles are not in the same place as the geographic pole (the axis of the Earth's rotation), but they're relatively close.
So: if you are standing at the equator, the magnetic field lines are pretty much parallel to the surface of the Earth, running pretty close to straight north and south. So the compass (3-d or regular) will have its north end pointing north, and its south end pointing south (a compass really points both directions!).
If you are standing at the magnetic north pole, the field lines are pretty much coming straight out of the surface of the earth; your regular compass would not know what to do, but your 3-d compass would have its north end pointing straight down, and its south end pointing straight up.
If you are standing at the geographic north pole, the field lines (and your needle) would still be pointing mostly down, but a little off to the side.
At the south pole, you'd get the opposite effect - the needle would point straight up at the magnetic south pole. The magnetic south pole is quite a bit farther from the geographic south pole (nearly 3000 miles), so the field lines at the geographic south pole would probably tilt quite a bit more than those at the geographic north pole.
But just as two north-ends of magnets repel from each other, shouldn't the north end of your compass needle repel from the north magnetic pole of the Earth, rather than be attracted to it? Turns out, the whole "north"/"south" comes from discoveries that one end of a magnetized needle "seeks" the direction of north - so really, the "north" pole of the magnet is really a "north-seeking" pole of the magnet. (and that means the Earth's magnetic pole up near Santa Claus is really a magnetic south!)

Casey O'Hara

Sorry for the delay in answering! I don't actually know the answers to most of these questions - but I'll tell you what I can.It's been a while since I've been there, but I don't recall being able to see the mountains from the South Pole Station. Most of the East Antarctic Ice Sheet is just a featureless flat white plain. The sticks in the ice would be a great idea - and for the work that happens down there now, they use all kinds of flags in the snow to mark the plane skiway, walking routes, and locations of cables and such buried under the surface of the ice sheet.
In terms of knowing whether you're at the south pole, with 1911 technology, I think the best bet would be looking at the angle of the sun. When you are at the exact South Pole, the sun's height above the horizon doesn't change throughout the day, since you are at the exact axis of rotation (well, there would be tiny motion due to the seasons, but very small). So you could measure the angle of the sun above the horizon several times a day, and when you get the same measure each time, voila!
Using such a technique, Amundsen's team of expert navigators took repeated rounds of measurement, getting a little closer to the pole each time. While there is always uncertainty in any scientific measurement, upon his return, he submitted his data for verification and the conclusion was that he had gotten within half a mile of the actual geographic south pole. Not bad!
As for time zones, I am not sure. Since the teams did not have the capability of communicating with outsiders, time zones would probably not have been particularly important. I'm sure they had a way of tracking the time, and could therefore report their arrival according to Greenwich time or any other relevant time zone. In the present day, of course, the logistics and communication all need to be coordinated with external sources, so it's important to choose a time zone and stick with it - so to keep it simple, we used New Zealand time, because the largest US Antarctic base, McMurdo Station, coordinates communication and logistics with the US Antarctic Program base in Christchurch NZ.
Cheers!
--Casey

Casey O'Hara

Sorry for the delay in answering! I don't actually know the answers to most of these questions - but I'll tell you what I can.It's been a while since I've been there, but I don't recall being able to see the mountains from the South Pole Station. Most of the East Antarctic Ice Sheet is just a featureless flat white plain. The sticks in the ice would be a great idea - and for the work that happens down there now, they use all kinds of flags in the snow to mark the plane skiway, walking routes, and locations of cables and such buried under the surface of the ice sheet.
In terms of knowing whether you're at the south pole, with 1911 technology, I think the best bet would be looking at the angle of the sun. When you are at the exact South Pole, the sun's height above the horizon doesn't change throughout the day, since you are at the exact axis of rotation (well, there would be tiny motion due to the seasons, but very small). So you could measure the angle of the sun above the horizon several times a day, and when you get the same measure each time, voila!
Using such a technique, Amundsen's team of expert navigators took repeated rounds of measurement, getting a little closer to the pole each time. While there is always uncertainty in any scientific measurement, upon his return, he submitted his data for verification and the conclusion was that he had gotten within half a mile of the actual geographic south pole. Not bad!
As for time zones, I am not sure. Since the teams did not have the capability of communicating with outsiders, time zones would probably not have been particularly important. I'm sure they had a way of tracking the time, and could therefore report their arrival according to Greenwich time or any other relevant time zone. In the present day, of course, the logistics and communication all need to be coordinated with external sources, so it's important to choose a time zone and stick with it - so to keep it simple, we used New Zealand time, because the largest US Antarctic base, McMurdo Station, coordinates communication and logistics with the US Antarctic Program base in Christchurch NZ.
Cheers!
--Casey

lol

could you please tell me compass direction in a easy way please

Ben Parker

Casey, thanks for your contributions to science and especially your dedication to educating these students with great clarity and respect. When you're ready to come in from the cold, I think you'd make an excellent science teacher!