Compass Knowledge Needed

Discussion in 'Other Skills' started by Shagaroo, Sep 18, 2018.

  1. Shagaroo

    Shagaroo Tracker

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    My son just joined the Cub Scouts and one of the first things they did was discuss compasses, navigation, etc. So I decided it was time to get a decent compass, and to learn more than the basics myself. The budget is crazy tight so I am trying to not break the bank but want more than a Wal-Mart $5 cheap-o. However, the differences make no sense to me.

    I looked at a Suunto MC-2 and there are like 4 different versions. There is the Nh Usgs Mirror Compass for $39. Then the /360/D/CM/IN/NH for $54. Another, Usgs Mirror Compass, for $57. Then a completely different Amazon page for Suunto has a MC-2, no other designations, for $42. They all look the same to me.

    Then I look at some place like Sportsman's Guide and they have a 2 pack of military style, metal, lensatic compasses for $15.

    Can someone make sense of all this for me? I just need a decent, but affordable, compass for a kid and dad to learn to navigate with.
     
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  2. Todd1hd

    Todd1hd Supporter Supporter

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    You will get 100 opinions and that is OK. All you need is either a Suunto A-10 or Silva Field series to start with. Maybe more important, spring for the book "Be an Expert with a Map and Compass" by Bjorn Kjellsrtom.
     
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  3. Gruxxx

    Gruxxx Supporter Supporter Bushclass I

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    I think for cub scouts, any basic, decently made compass will be fine. It should have bearing graduations on the dial and be adjustable for declination, and perhaps have a common scale marked along the flat base, but that's about it. There's no need for a mirror at his level, which is used to take an accurate sighting bearing on a distant object, while reading the compass in the mirror. I think you'll be fine being budget minded here.
     
  4. Primordial

    Primordial MOA #40 Supporter Bushcraft Friend

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    For CUB scouts. I would just get any cheapo that points North. A kid may lose, or break one so I think going budget will be better.
     
  5. riokid87

    riokid87 Scout

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    I've had a military lensatic compass sinse about 1988. It still points true. The tritium has worne out years ago but still charges with a blast from a flashlight. I think you can get one w/o tritium at Cabelas for around 60 bucks.
     
    Last edited: Sep 18, 2018
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  6. Metaldog

    Metaldog Scout

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  7. RavenLoon

    RavenLoon axology student Supporter

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    I think you are looking for a compass for yourself to get better at navigation and not for your cub scout, right? For cub scout I would get a simple baseplate compass with a rotating dial like the Suunto A 10. It's a good basic compass for adults too. For serious adults I would recommend your mentioned Suunto MC-2. You don't need the global unless you travel to other hemispheres. That is the type preferred in many natural resource professions. Look at similar models by Brunton. It depends on which sighting method you prefer. The military uses the Cammenga type compass which has a different sighting method. It is preferred by many who learned navigation in the military.
     
  8. Primordial

    Primordial MOA #40 Supporter Bushcraft Friend

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    Ahhhhhh....I misread your question. I some how didn't notice it was for your use and skill building! Sorry. I thought you were looking for a compass for a child to use in cub scouts.
     
  9. Kona9

    Kona9 Supporter Supporter

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    BOTH of you should get the same, inexpensive Silva or Suunto compass. He will be excited as he has the same one as you, and you can both learn how to use it together. You don’t need to spend more than $10-$15 each on them. Myself and my boys use the Suunto A-10’s mentioned above. Books on learning how to use them would be a better investment. Later on get a fancier compass if you master using the basic ones.
     
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  10. Swampdog

    Swampdog Supporter Supporter

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    Buy once, cry once... Sunnto MC-2 for Dad and a Silva Starter for the Cub Scout.

    A decent book to learn the basics is: A Falcon Guide, Basic Illustrated Map and Compass check out: www.falcon.com

     
  11. Crusher0032

    Crusher0032 Appalachian Arthfael Supporter

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    I can't recommend a Brunton TruArc3 high enough. Easy on the wallet, made in the US, weighs 1.1 oz, tool free declination adjustment. Might want to give it a look. Have one for each hiker in my family and have been really happy with them.

    https://www.amazon.com/Brunton-TruArc-3-Compass/dp/B079VQXDGH
     
  12. Pinelogcreek

    Pinelogcreek Supporter Supporter

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  13. oathkeeper762

    oathkeeper762 Bushbum & PT Wanderer Supporter Bushcraft Friend Bushclass I

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    Be Expert with Map and Compass https://www.amazon.com/dp/0470407654/ref=cm_sw_r_cp_tai_NVJOBb290XD5G


    As an old scouter and merit badge counselor who’s taught a lot of orienteering, I highly recommend you get a copy of this book and any starter compass with a decent baseplate will suffice to get you started. As you gain skills and if you and your son decide to continue with advancing your orienteering skills you can purchase a more precise compass with all the bells and whistles. Hope this helps, it’s a great book less than $10 and will really help you with your learning. YMMV
     
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  14. backwoodstrails

    backwoodstrails anatidaephobic Supporter Bushcraft Friend

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  15. Outdoor Dauber

    Outdoor Dauber Scout

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    If you're going for a simple baseplate compass, I'd recommend a SikvS or Suunto. They should be less than $15 or so. However, for a more versatile compass, I would suggest the UST mirror compass. No, it's not as smooth or durable as the MC-2, but I recently bought one for my 12 y.o. daughter to teach her about orienteering. It points the same direction as my MC-1, has adhuadjust declination, can be used as a baseplate compass on a map or used to shoot bearings in the field. They are about $10 at Field & Stream, etc.
     
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  16. JoeJ

    JoeJ Supporter Supporter

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    I whole heartily agree with the premise buy once, cry once when it comes to purchasing an important item. Myself, I like the idea of a mirrored compass that can be used as a mirror to see your "backside" if you happen to injure yourself or need to inspect some part of your body that you couldn't see otherwise or use as a signal mirror. Chances of me ever using a mirror on a compass for those purposes is extremely remote IMO, so I've never purchased a mirrored compass.

    I would highly recommend reviewing various sites for best prices - here's a site I favor:
    https://www.forestry-suppliers.com/Search.php?stext=compass

    I would recommend the Suunto M-3 NH - myself, I have and use the Suunto M-3 D, which is an earlier model of this newer M-3NH. Of course, it's hard to just have one compass, so I also possess the Suunto KB-20.:53:

    If you're not going to be using maps in conjunction with the compass - then a $3.00 key chain style compass will give good enough general directions. But if you're going to be involved in plotting courses on a map and then actually going out and attempting to find an item in your compass class - then a compass similar to the Suunto M-3 NH will be the tool to do the job.

    I would also recommend a good reference book, so when you actually attend these classes everything will make more sense. For my grandkids I got them a book called Wilderness Navigator - second edition by David Seidman. Some of those classes can be a real challenge. When I took a class many decades ago we had to plot a course to an area containing a plastic quart jug colored red - the actual course covered approximately 5 miles shooting around "obstacles" which was the easy part - once in the "area" we had to locate the jug by walking a grid and that took an hour plus to find it - coming out at a different point we could have found it in 10 minutes but ole man Murphy decided to come out and play. Enjoy the outdoors with your Cub Scout and when he goes for his Eagle Scout, I'll bet he'll still be using that compass you purchased for him.:dblthumb:
     
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  17. marbleman

    marbleman Supporter Supporter

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    Here's an easy compass/orienteering/pacing practice. Pick a spot in your yard, drop your hat (or anything). Take ten paces north, turn 90 degrees right. Ten paces east, turn 90 degrees right. Do the same for west and north. You've walked in a square, and wound up back at your hat. Being able to see the hat from afar makes it easy to cheat. Put something small in the lawn to mark the spot and make it 100 paces instead of 10.

    Then, offset it by 15 degrees (or whatever). Instead of straight north, go 15 degrees, turn 90 degrees, etc. Or make it three 120-degree turns, instead of four 90-degree turns.

    If you really are lost, then orienteering/direction finding could be more important than counting paces, but paces can give you an idea of how far you have traveled. Get some pace beads. They're cheap, fun, and help.
     
    Last edited: Sep 19, 2018
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  18. latvija

    latvija Tracker

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    The very first time I laid hands on a compass (Silva Guide), I tried this exercise. But instead of my hat, I dropped my car keys in the deep, thick grass. I figured putting some skin in the game would make it a bit more worthwhile. I screwed something up and was on my knees for the better part of an hour looking for those keys.

    The second time with the same compass and a bit of patience and humility turned out much better.
     
    Last edited: Sep 19, 2018
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  19. Yknpdlr

    Yknpdlr Tracker

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    Learning how to use a compass is a critical outdoor skill. Whatever model you choose (I prefer the Suunto M-3 type), understanding how to use it is imperative. Most useful is a flat baseplate orienteering style compass with a smoothly rotating easy to read bezel (dial). be sure it has a set of parallel orienting lines inscribed on the bottom of the rotating bezel (some Brunton models do not). The A-10 would be perfectly fine for the cub scout. Although my collection includes several, IMO a mirrored compass ( such as on the MC-2) is unnecessary and does not significantly increase accuracy unless you need it for shaving.

    Know what the declination diagram means and how to apply it during travel with map and compass together. Depending on model and cost, your compass may or may not have a declination adjustment. If not, do the adjustment in your head, with understanding of using the declination diagram as a guide. Too many people are easily confused by the dec diagram with compass. Learn it explicitly and don't forget how to use it without relying on silly word memory games. Don't confuse the cub by trying to go too advanced with declination. Simple use of the compass alone is enough at that age. However, if you understand and can do terrain association based on a good topographic map using your eyes and brain while observing and scanning the landscape , with practice you will hardly need to use a compass at all in the back country.

    For many years (>25) I have taught land navigation skills to wilderness guides, to SAR teams and to officers of law enforcement agencies for a division of Homeland Security.

    Don't go crazy with instructional books. The Kjellsrtom book is the old basic standby from years ago, although it is rather dated. I do now prefer and recommend: The Essential Wilderness Navigator: How to Find Your Way in the Great Outdoors, Second Edition by David Seidman and Paul Cleveland
     
    Last edited: Sep 20, 2018
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  20. wizard

    wizard Guide

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    I learned to use a compass and a map years before going into the Army. In the Army I used the military compass a lot but found the simple baseplate model I was accustomed to was much more versatile. I stopped using the military, heavy metal compass.
    I see no need to buy a compass with a sighting mirror, there are some uses for the sighting compass but the average user is only affected by higher cost of ownership and little return on that investment. My compass that I use today is a Suunto MC-3G, it is a global needle model, which is only useful if you travel the world. The standard Suunto MC3 is more than a precise, easy to use compass and is much less expensive.
    The book mentioned by others, "Be Expert with Map and Compass" is an excellent source of basics and is well worth owning. It is a workbook also, that has you work through various navigational exercises. I review mine every 5 years or so to stay fresh.

    All the best to your Cub and to your learning experience.
     
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  21. Top Gibson

    Top Gibson Supporter Supporter

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    The Brunton TruArc 3 is a great compass. I keep mine in my belt pouch.....and I keep my Suunto MC-2 on my pack strap.
     
  22. Leshy_apprentice

    Leshy_apprentice Scout

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    There are several makes of compass that are fine, you already heard the biggest names and any one of them will do the job at his basic learning level.

    I'd recommend you buy the cheap, basic baseplate compass for your son now, just as an inexpensive learning tool that doesn't have to be perfectly accurate...you're not dropping him off alone in the woods to land-nav back only by compass where being off from magnetic north a degree or two is critical. Also, starting off with the basic compass will force him to learn about magnetic declination so he actually understands the cause of it, why to compensate, and how to do it. If you start him off with a "set it and forget it" magnetic declination offset screw, he's less likely to think through and understand the declination phenomenon, which could be a handicap in the future when he might need to know. Better to learn it from the start, in my opinion, or at least learn it after he has a solid grasp of the basics, and then explain declination.

    The 2nd part of my advice is to get yourself a decent orienteering compass with sighting mirror now. I like the flip top mirror style with clear baseplate so you can set it on a map and still see through to the map features. I have a Silva, and used it professionally in the wilderness, as well as recreationally. Like I said, though, any reputable maker will do. Use that compass yourself, and Google compass and orienteering training...many high quality, and easily understandable learning resources are available free online. You can teach your son the "beyond the basics" stuff with your orienteering compass together. And when he's ready with skills and knowledge to upgrade to an orienteering compass himself, it'll be a special gift you can give him "dad's compass" as his own. He'll cherish it and the memories.
     
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  23. slysir

    slysir Guide

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    I agree with others that stated any starter base plate will do. As for the book "Be expert with map and compass", Practically every library in the USA will have one in inventory.

    -John
     
  24. BradGad

    BradGad Supporter Supporter

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    I disagree with the advice to go as cheap as possible for the boy's compass. I'm going to assume he's a responsible young lad until told otherwise.

    A good basic compass doesn't cost much at all. 1) A quality basic compass might be all he (or you) needs for the long haul, and 2) there is -- later -- real joy in gear you got when you were a kid and are still using decades later. Sure, some gets lost, some gets broken, some becomes obsolete, but some doesn't. I still have and use half a dozen pieces of gear from my scout days, and they are precious to me.

    My old compass is a Silva. I maintain that back then they were the best brand of orienteering compasses. They have outsourced production, though, and now I would give that title to Suunto.

    You mentioned you looked at the Suunto MC-2. That’s a good little compass but I would suggest something like the Suunto A-30 would be a better choice and a better value.

    I see you (like me) live in Georgia. When I was younger and backpacked a fair amount in Texas and the Rockies -- where you get long sight lines and can use two distant points to triangulate where you are with great accuracy -- the sighting mirror on my Silva was very useful. Here in Georgia, where I'm hemmed in by trees 98% of this time, I never use it.

    The slightly longer base plate on the A-30 will be more useful here than the sighting mirror. And, it will probably be a bit lighter and more comfortable to carry. And, I'm pretty sure they're made to the same quality (very high). And, the A-30 costs 60% less.

    +1 on the recommendations for Be Expert With Map and Compass.

    Finally, a declination adjustment is useful but there's something to be said for learning to do it in your head before you rely on an adjustment mechanism: until you "get" declination, it would be easy -- since the terminology is rather counter intuitive -- to dial in the adjustment opposite of what it should be. Even better is learn when and how you can work from magnetic north only, making it a non-issue. (FWIW, declination in Georgia is currently 5-6 degrees west... *usually* not enough to make a drastic difference in your navigation.)
     
    Last edited: Sep 20, 2018
  25. gohammergo

    gohammergo I like sharp things.... Supporter

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    I agree that you should get a decent one for both of you. If you get him a cheapo one and it isn't very accurate, or breaks, that may discourage him from any real interest in it beyond the scouts. Decent ones aren't terribly expensive.
     
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  26. BradGad

    BradGad Supporter Supporter

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    Actually I just talked myself into a Suunto A-30, to have as a back-up compass and/or a more pocket- and Georgia-friendly alternative to my Silva Ranger.
     
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  27. twyych

    twyych Tracker

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    This is exactly what I came to say; make sure you get the correct hemisphere. You can also get a "G" (global), which works in either hemisphere.
     
  28. rayj

    rayj Tracker

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    For a quick start on using the compas do a search for the Silva 1,2,3 method of learning to use a compass. The basics are covered well in the short description. If you decide you want more then get the afore mentioned books but more importantly find some people that use compasses and learn from them. A compass can be confusing but is an absolute neccassary skill to learn. I used mine in the Forest Service for a variety of jobs from trails/lookout to fighting fires. As a smokejumper we would many times fly and jump fires in unfamiliar country without the luxury of having seen the terrain/aspect the fire was burning. The compass and maps were our besr friends for sure!! Especially for figuring best packout routes. Whatever compass you aand your Son end up with...practice practicepractice. Good map skills are critical too.
     
  29. CSM1970

    CSM1970 Guide

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    Almost any compass will point North, but what you are really buying is build quality. Liquid filled compasses get air bubbles, cheap compasses have plastic pivots that wear, etc. The Suunto MC2 is a great reliable compass.
     
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  30. Beach Hiker

    Beach Hiker Traveller Supporter Bushcraft Friend

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    @Todd1hd
    Thanks for the book recommendation. ... I will order it!
     
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  31. ReallyBigMonkey1

    ReallyBigMonkey1 Scout

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    I'm a little shocked at all the negativity towards mirrored compasses. I was a scout leader and if you give a kid a baseplate compass only to navigate with then you're teaching them from the get go that being within a few degrees is ok. I think it's a good habit to start them out with a mirrored compass so they can hold it up to eye level, peer through the sight hole and accurately sight in on a target. Just my opinion from teaching kids.
     
  32. Yknpdlr

    Yknpdlr Tracker

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    I did not notice a lot of negativity toward mirrored compasses. if that is what you have, go ahead and use it to your maximum ability.

    I only stated that I don't believe the perceived increase in accuracy was actually there, nor in most cases necessary. I've been teaching land navigation since 1975, initially to Boy Scouts, then formally to Adirondack wilderness guides in training for licensing, then and now to SAR and law enforcement for the NY State division of Homeland Security and Emergency Services. Young scouts, college age wilderness guides, older SAR team members, and SWAT or patrol cops, all have a learning curve, some much steeper than others. Basic understanding in totality of how back country navigation works and practiced skills is more important than trying to use a compass to walk a course within a degree of targeted measurement.

    As I am mostly self-taught through making my own off trail experiences over the years, my first real precision compass was a Silva Ranger, circa 1970,which I had always thought of as my old friend and companion in the woods. I was heartbroken when a few years later it developed a bubble. So I bought a replacement Silva, which IMO was definitely of inferior quality, so I replaced that one with a Suunto. The Suunto equivalent mirrored compass was considerably better than the then current Silva. But both are on the heavy side. I decided then to buy my first Suunto M-3 style without a flip open mirror. I soon discovered, used properly, it was just as accurate as any mirrored compass. I now have about 20 of that style that I use personally and to loan out for training of others. I teach proper stance and holding of the compass while viewing a target in the forward field of view, something that takes instruction and training with any style of compass, mirrored or not. Pay attention to what the terrain is doing in all directions.

    If you are using all available (non-electronic) navigation tools, namely terrain association with a good map as the primary method, there is no need to be more accurate than 2-3 degrees in heading. Just watch where you are going and relate any changes to the map. Even with a mirror sighting compass I doubt that you can get better than 2 degrees of real accuracy anyway, whether holding it up to your eye for sighting or not. You don't need survey quality precision to navigate from one point in the woods to another. Navigating in featureless open desert or tundra terrain is a different story.

    As for teaching the skill, students learning how to use a moderately priced quality flat baseplate compass while teaching terrain association and a little interpretive brain power with a topo map will provide all the skill and accuracy most people of any age can handle until they gain sufficient personal experience to venture out themselves. Practice, practice, practice and early error detection when the inevitable mistakes are made will get you going most everywhere.
     
    Last edited: Oct 7, 2018
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  33. charlesmc2

    charlesmc2 Scout

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    I guess I'm in the non mirror corner. Where most of us operate the map is the key tool, not the compass.

    Incidentally, and the main reason I am joining the discussion, is take a closer look at declination. If you are an older guy like me and thinking in terms of grandchildren's learning, declination has changed a good bit. When I was a kid growing up in East Texas, the compass pointed 7° east of due north. Now it is only 1°. Polaris is not much closer than that.

    Little known is that Polaris was closest to due north in the late 90's. Of course that changes very slowly. It "moves" due to the precession of the earth's axis not the true motion of the star. It is so far away we can pretty much ignore it's proper motion. In another 20 odd thousand years our axis of rotation will again be pointing to Polaris. Along the way we will have times when there is no "north star" and IIRC at some time we will have a much brighter star, Vega, as north star. I'll go way out on a limb and predict I will not live to see that.

    In our time, we in the northern hemisphere are actually closest to the sun in the winter. Not only do we receive a bit more solar radiation due to this, but because we are closest to the sun in winter the earth flies faster through space and winter is a couple of days shorter than summer. That probably makes a bigger difference to our climate. I'm not sure what the current thinking is, but I believe the thought is this contributed to the last major ice age which ended 10,000 years ago or so. Studying compass and the like can be a valuable introduction into observational astronomy. Like where does the sun (and moon) rise by compass angle. When the sun is furthest north in summer, the (full) moon will be furthest south. And the moon, unlike the sun, drifts north and south of its average location. This leads to why we have eclipses, but not every month. I've been trying to teach my grandkids to know where the sun is by looking at the phase of the moon and to know that you have a full moon when the moon rises as the sun goes down. Or that a half moon happens when the moon rises around midnight. Another is that the moon rises about an hour later each day. And so on.

    If your eyes are rolling back in your head, studying this also gives us a much greater respect for our ancestors who gradually worked all this out over the centuries. And they had it worked out thousands of years ago. The Greeks figured out the diameter of the earth in, what, 500 BC. (BCE for political correctness) I'm only figuring a lot of this, now, in late life.

    Our grandparents, great grandparents and so on knew a lot of this much better than we do. They watched the heavenly progression rather than TV or, now, internet. Understanding this will give your kids (grandkids) a significant advantage. It might even teach them to respect their elders! I cannot but state my own belief that the design of the solar system was not accidental. I believe God put it here, they way he did, in part to tutor mankind. It IS an amazing coincidence that the disc of the moon and of the sun are so similar. But that is another story.
     
    Last edited: Oct 8, 2018
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  34. Outdoor Dauber

    Outdoor Dauber Scout

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    Current declination at my location is 11 deg, 23 min W. That can become an issue...1 deg, not so much.
     
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  35. JoeJ

    JoeJ Supporter Supporter

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    If your declination is 11 degrees then you are probably living in an area where you can see an object that would take a week to walk to?:3:
     
  36. Outdoor Dauber

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    Um no, not really. Unless I'm on a ridgetop.
     
  37. Yknpdlr

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    Charles, I 'm actually quite surprised that your declination has changed by such a large amount in your lifetime. Generally the magnetic polar wander is rather slow, small fractions of a degree per year in the mid-latitudes. Got any volcanoes emerging nearby that might have altered the local magnetic field? Anyone can google their location to see the current-day declination and its average annual rate of change. For me in the northeast, with declination at around 12 degrees west, it hasn't changed by more than a degree in the past 40 years since I've been a backcountry traveler and instructor of land navigation.

    On eclipses, the sun follows the exact same apparent path each year throughout the year (the ecliptic), but the plane of the moon's orbit is tilted about 5 deg to the plane of the ecliptic. It is only when the moon happens to cross the ecliptic at the same time that the sun is either in the same apparent location ( for a solar eclipse) or exactly opposite (for a lunar eclipse). Tidal friction is causing the moon to slowly recede away from the earth, so that future generations (far future), will only be able to see annular solar eclipses, not total. It is a bit of a miracle that we happen by chance today to live in an era wherein the apparent size of sun and moon nearly exactly coincide.

    More on magnetic declination. Of course, you can completely ignore declination if you are navigating using only the compass without a map being involved. All azimuths, headings, tracks, routes, and course lines will be relative to magnetic north only. Declination only comes into play when you relate the compass to the map to make and convert azimuth measurements from one to the other. The easiest way for me to remember how to do the conversion from magnetic to true (or grid), or vice versa, is to look at the declination diagram which is, or should be, represented on every navigation map. When converting azimuths from map to compass (or vice versa), you must convert from true to magnetic (or vice versa) using declination. Just remember that azimuth measurements taken from or to the map are relative to a true north reference line. Measurements taken from or to a compass are relative to a magnetic north reference line. A compass is no more than a protractor, measuring angles clockwise relative to some given reference line, could be true or magnetic, depending on how you use it.

    When I teach the stuff, I, or my students, make ourselves into a compass diagram using our arms as reference lines. No need to (mis)remember any silly word mnemonic. If declination is west, point your left arm ahead and slightly to your left, representing magnetic north. For east declination, point your right arm slightly to the right of straight ahead, representing magnetic north. In either case, point your other arm straight ahead, representing true north.

    Now imagine you want to convert a given azimuth to find the true or magnetic azimuth of some imagined object, say approximately 45 degrees to your right. If the given azimuth measurement is taken from a map, the 45 degree true angle is made from your straight ahead true arm representing true north. Ask yourself, is the measurement from my other (magnetic reference) arm a lesser or greater angle than that from straight ahead? The answer will tell you whether to add or subtract the declination value to the given azimuth for the conversion to magnetic. If your were given the 45 degree magnetic azimuth measurement from a compass to an object, ask yourself: is the measurement to the object from the other (true reference) arm a lesser or greater angle to convert to true?

    It sounds complicated, but work through a couple of examples yourself and it becomes very clear what to add or subtract to what. By the way, it doesn't matter how large the angle actually is to an object, the example of an object imagined toward your forward right (say 45 degrees) will always give the correct answer.

    Graphically,
    To convert from MN to TN/GN, or from TN/GN to MN (Do this when going
    From compass field azimuth to map plot azimuth, or vice versa)
    From viewing the Declination Diagram:

    Imagine an object in the first quadrant (regardless of the actual angle to your object of interest)
    -visualize the MN azimuth to the object and the TN azimuth to the object.
    -Ask “which angle is larger?”
    -Add or subtract declination value as needed to convert to the larger or smaller desired reference angle.
    [​IMG]
     
    Last edited: Oct 8, 2018
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  38. woodsranger

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  39. charlesmc2

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    I was very much surprised declination had changed so much as well. I’m in Texas and no volcanic surprises. USGS has a good map of this and I rechecked this last fall so I believe I am accurate on the amount of change. The maps show smooth lines so nothing big there. It changes more in North America than in Europe sine we are closer to magnetic north in Canada.

    The actual change is only a little more than one degree every decade over the last 50 years or so.
     
  40. SoreFeet

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    There was a post a month or two back about compasses with big lettering for us old farts with poor eyes. I can't find it now. Would somebody point me in that direction?
    Sorry for getting a mite off topic.
     
  41. woodsranger

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  42. SoreFeet

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    @woodsranger I appreciate your help! Seems like easy to read and quality isn't a popular combination for compasses.
     
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  43. woodsranger

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    Yep. And it's too bad, because people such as yourself, and myself, and probably millions of other people in their older years, would love to have bigger numbers and letters on everything!
     
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