Map and Compass Honor

The Pathfinder Map and Compass honor is the stage where orienteering in the Pathfinder Club gets precise: UTM coordinates, the angles between the three norths, magnetic declination and a course with at least ten control points.

The full requirements of the Map and Compass honor are in the catalog (code AR-021) and are summarized here, with no answer key. Scale, contour lines and the legend are covered in the guide to reading topographic maps; basic compass use, in the one on orienteering with a compass. This text starts where those two stop, with data checked on October 6, 2026.

🧭What is the Pathfinder Map and Compass honor and what are the requirements?

The Map and Compass honor has the code AR-021, belongs to the Recreational Activities area and sits at difficulty level 3. According to the catalog, it was created in 1956 by the General Conference of the Seventh-day Adventist Church.

On the card for the advanced New Frontiers Ranger class (Pioneiro de Novas Fronteiras in Portuguese), published by the South American Division (SAD) on adventistas.org, item 4 asks Pathfinders to complete the Map and Compass honor. The Ranger class starts at age 13. After this honor, the catalog offers the Orienteering with GPS honor (AR-104), created in 2012 by the SAD.

AR-021 requirements from the Desbravai catalog, summarized with no answers; your instructor's wording is what counts.

🌐How many UTM zones does Brazil have and how do you read UTM coordinates?

UTM (Universal Transverse Mercator) is the projection adopted for Brazil's systematic mapping, according to the manual Noções Básicas de Cartografia (Basic Notions of Cartography) from IBGE, Brazil's geography and statistics institute. It divides the world into 60 zones, each 6° of longitude wide, numbered eastward from the antimeridian (180°), and it applies between latitudes 84° N and 80° S. Each zone has its own central meridian and grid: the straight lines in meters that the requirement calls the grid system.

The origin of each zone is where the central meridian crosses the Equator. There IBGE sets the E coordinate (easting) at 500,000 m and, in the southern hemisphere, the N coordinate (northing) at 10,000,000 m, so there are no negative numbers. An easting below 500,000 m means a point west of the central meridian, and the smaller the northing, the farther south the point lies. Without the zone number, the same pair of E and N values repeats in all 60 zones.

Brazil spans eight zones, 18 to 25, according to IBGE. To find your city's zone, add 180 to the longitude (west as a negative number), divide by 6 and round up: São Paulo, at 46.63° W, gives 133.37 ÷ 6 ≈ 22.2, so it falls in zone 23. In the zone's name, the number is followed by the hemisphere letter (S, south of the Equator). For the SAD, do the same calculation at the extremes of its eight countries (Argentina, Bolivia, Brazil, Chile, Ecuador, Paraguay, Peru and Uruguay) and agree with your instructor on whether ocean islands count.

Brazil's UTM zones according to IBGE (figure 2.14).

🧲True north, grid north and magnetic north: which angle is meridian convergence?

The map reading guide introduces the three norths; the honor asks for the name of each angle between them. For IBGE, magnetic declination is the angle between true north and magnetic north, and meridian convergence (also called grid convergence) is the angle between true north and grid north.

Convergence comes from flattening the curved Earth onto paper. It is zero on the central meridian and, according to IBGE, grows with latitude and with distance from that meridian. Even so, it is small. An approximate surveying formula multiplies the difference in longitude from the central meridian by the sine of the latitude: in São Paulo, 1.63° × sin 23.55° ≈ 0.65°, against about 22° of declination.

Both angles appear in the declination diagram in the map margin. In the U.S. Army land navigation manual (TC 3-25.26, from 2013), a star usually marks true north, GN marks grid north and a half arrow marks magnetic north. The drawing is rarely to scale: the number printed next to it is what counts.

📍What is the magnetic declination in Brazil in 2026?

At every point we checked, from Acre to Fernando de Noronha and from Roraima to Chuí, the needle points west of true north. The values come from the calculator of NOAA, the U.S. National Oceanic and Atmospheric Administration, using the World Magnetic Model WMM2025 (valid through the end of 2029), for October 6, 2026. They range from about 7° W at the western tip of the state of Acre (Mâncio Lima) to almost 24° W on the coast of Espírito Santo, with an uncertainty of 0.3° to 0.4°.

Ignoring declination is costly. TC 3-25.26 calculates that each degree of difference pushes your path about 18 meters to the side for every 1,000 meters. With 22° forgotten, the exact calculation (1,000 m × sin 22°) gives about 375 meters of error per kilometer walked.

NOAA/NCEI, WMM2025 model, center of each capital; “increases” means more degrees west each year.

Read alsoWilderness Living Honor→

🔍What are the parts of a Silva compass and how do you draw one?

The Silva-type compass, also called a cartographic or baseplate compass, takes its name from the Swedish brand founded in 1933 by the three Kjellström brothers and Gunnar Tillander, according to the company itself. Ordnance Survey, the British national mapping agency, considers this type probably the most versatile, because it takes bearings, sets the direction of travel and measures distances. The names of the parts are in the compass orienteering guide; in the drawing for requirement 9, add what each one does when you take a bearing from the map.

Ordnance Survey sequence, adapted to Brazilian declination.

🔄How do you convert a true azimuth to magnetic and calculate a back azimuth?

An azimuth is the angle measured clockwise from north, from 0° to 360°, according to IBGE. Measured with a protractor on the map, it is true (or grid); read on the compass, it is magnetic.

NOAA sums up the conversion in one line: true azimuth = magnetic azimuth + declination, with west declination negative. In Brazil, add the declination going from map to compass; subtract it going from compass to map. In São Paulo, with 22° W, 40° measured on the map becomes 62° on the compass.

The back azimuth is the azimuth of the opposite direction (IBGE), and it lets you return the way you came. Following TC 3-25.26, add 180° to azimuths of 180° or less and subtract 180° from larger ones: 62° becomes 242°. The manual warns that a mistake in this simple calculation can have serious consequences.

Deviation has two meanings in the field. One concerns the needle: metal objects and electrical sources throw off the reading, and the fix is to move away. The other concerns your route, when you go around an obstacle: TC 3-25.26 says to walk at right angles (on a 90° bearing: 100 m at 180°, 150 m at 90° and 100 m at 360°) and then resume the original azimuth.

Source: TC 3-25.26 (2013).

🛰️What is an orthophoto map and which symbols should you study on a topographic map?

An ordinary aerial photo is a central perspective of the ground. IBGE defines an orthophotograph as that photo transformed into an orthogonal projection onto a plane, and an orthophoto map as the orthophoto completed with symbols, lines and georeferencing. That is the orthophoto map in requirement 8: it looks like a photo and has the geometry of a map.

For the symbols, use the topographic map of your region; in Brazil, IBGE's systematic mapping uses scales from 1:1,000,000 to 1:25,000. The legend colors are in the map reading guide; the list below helps you build the notebook of 20 symbols in the groups of requirement 7.

IBGE, Noções Básicas de Cartografia (1999), chapter 3. Always check the legend on your map sheet.

✅How do you prepare for the 10-control-point course?

In the field, distance is measured in paces. Keep a pace count of double steps (one number each time your left foot touches the ground) over a measured 100-meter stretch and average a few tries. TC 3-25.26 warns that your pace shortens going uphill (someone who takes 120 single steps over 100 m on flat ground may need 130 or more) and suggests putting a pebble in your pocket every 100 meters.

Carry a log sheet like the example below. For requirement 11, orient the map by visual inspection, turning it until roads, rivers and hills line up with what you see; or lay the compass along a north-south line and turn both together until the needle sits west of map north by the amount of the declination.

Common mistakes: reading the compass near a car or a wire fence, adding the declination in the wrong direction, writing down a bearing reversed by 180° and using a compass with more than 3° of error, the limit set by TC 3-25.26.

How to set up the course is explained in the guide to the orienteering race at the Club. Walk in pairs, carry a whistle and agree with your Counselor on what to do if you lose your bearings, as in the guide what to do if you get lost. Before your evaluation, check the full requirements of the Map and Compass honor.

Fictional example, with a declination of 22° W and 65 double paces per 100 m.