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These are the contents of SURVIVAL sub-page re-organized in book order for coherent reading.

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NAVIGATION (Celestial).

The Sun, the Moon and identifiable stars are used to work out North direction and time in this section.

divider43.jpg

Finding accurate directions by a watch .. Posted on May 12, 2015.. This is my novel technique.

WatchCompass_22NL

Finding accurate directions using a watch, posted on May 19, 2015 . This is my novel technique to replace the horizontal watch method.

DirectionBySun_12N

Caution in finding North by bisector line of a horizontal watch. Posted on October 28, 2015: The commonly known “Scout method” using a horizontal watch may give directional errors of up to 180 degrees in some circumstances.

wpid-bisectorns2c.jpg
, posted on 2018 July 10

Find North By Fingers
, posted on May 06, 2015 . <<<—This is my MOST USEFUL novel technique.

wpid-dividermwp3e2c2.jpg

find North by the Sun

CloudyL

Finding North direction and time using the hidden Sun via the Moon . Posted on July 6, 2015This is a useful technique.

image

Finding North direction and time accurately from the horn line of the Moon. Posted on August 12, 2015. This is my novel technique.

image

Finding North direction and time using the Moon surface features. Posted on July 1, 2015. This is a useful technique.

image

, posted on

Finding North and time by stars. Posted on August 28, 2015

Sky map Northern 3/4 sphere

Sky map Southern 3/4 sphere

Finding North and time with unclear sky. Posted on October 17, 2015. This includes my novel method for finding North and with unclear sky.

image

image

posted on October 21, 2016

ariessmallc30.jpg

. Posted on May 25, 2016

mercator8gc30.jpg

. Posted on April 05, 2018

star map mercatorx1p6

. Posted on April 12, 2018

. Posted on May 13, 2018

. Posted on September 16, 2018

Find North with Orion Equatorial stars

, posted November 3, 2016

slide-sky-disk

Slide Sky-Map for displaying tropical stars, posted on October 7, 2016

photo

, posted July 22, 2016

DirectionTimeByStars

Finding time to Sunset with bare hands. Posted on November 11, 2015 .This is my novel improvement for improved accuracy.

wpid-sunset2.jpg

Finding time to Sunrise with star maps, Posted on January 9, 2016 . This is a novel application for star-maps.

sunrise

Finding direction, distance and navigating to a distant base by stars (Part 1). Posted on January 27, 2016 . This is a novel application for direction of stars in the sky.

Sky map Northern 3/4 sphere

Sky map Southern 3/4 sphere

Finding direction, distance and navigating to a distant base by stars, fine reading of latitude (Part 2).. Posted on February 6, 2016. This is a novel way of accurately arriving at any chosen destination latitude using no instrument.

BStarsN20Vega8C2.jpg

NAVIGATION using only constellations.

The Orion constellation., posted December 26, 2016

The Scorpius constellation, posted on January 8, 2017

The Southern Cross Pointer stars, posted February 26, 2018

NAVIGATION (Terrestrial).

Measuring angles and distances for outdoor survival, posted on June 29, 2016

DistPole

NAVIGATION (Instrumental).

Finding North with a lensatic compass, posted on August 21, 2017

Compass-Magnetic

Determining local magnetic declination by a magnetic compass, posted on March 31, 2016

Compass-Magnetic

, posted on June 14, 2016

compass Reversal

Selecting and using magnetic compasses, posted on July 9, 2016

Compass Lensatic Jap

Shadow stick navigation and graph of solar paths, posted August 19, 2016

ShadowStick

Using GPS in off-grid situations, posted December 06, 2016

Adding longitude and latitude lines to a map, posted August 23, 2017

Map w Coordinates

Navigating with an AM MW radio receiver, posted January 17, 2017

radio sony

Finding North direction and time using geological features, plants and animals, posted August 04, 2017

FIRE MAKING.

Making fire and lighting cigarettes with sunlight. Posted on February 27, 2016

StormWatchDiagram

Quick fire making using sunlight, posted on January 4, 2017

20161222_131508gballfirec60.jpg

Mirror for making fire using sunlight., posted on April 13, 2016

20160105_143215C

Predicting-the-temperature-of-a-habitat, posted on August 31, 2017

compass thermometer

, posted October 23, 2018

Pushing away

FOOD

Rice as emergency food., posted December 24, 2016

20161230_192839ricegrains2c60.jpg

Dried-sweet-fruits-as-energy-food, posted December 24, 2017

Air-grown-mung-bean-sprouts-for-food, posted March 07, 2016

MISCELLANEOUS

Old maps:

Interesting maps of old Saigon , posted on March 20, 2016 .

SaigonThanhQuy

Detecting Counterfeit Currency

Detecting Counterfeit Currency, US dollars, posted on July 15, 2016

Hologram

, posted on November 15, 2016

polymer 5 dollars transparent stripe

Cashless bartering

Cashless-bartering-for-survival, posted on February 20, 2017

crystalball2c70.jpg

Other languages:

Survival-topics-available-in-other-languages , posted on june 18, 2017 .

click to go to polymeraust100dollarsMONEY , 20160105_145215CHOW TO , 20160105_145215CSOCIAL ISSUES , 20160105_145215CLIVING sub-pages

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Good approximation to solar declination by a watch face

Good approximation to solar declination by a watch face

by tonytran2015 (Melbourne, Australia).

Click here for a full, up to date ORIGINAL ARTICLE and to help fighting the stealing of readers’ traffic.

(Blog No.53).

#solar declination, #watch face, #multi-dial watch face, #Solar navigation, #find North, #time, #survival.

The value of solar declination is needed for accurate determination of North direction and time using a divider or a watch (references [1], [2]). Good approximation to solar declination is required by the methods to produce accurate results in cold temperate zone and arctic zone. The required value of solar declination can be simply obtained using only a watch face or even the drawing of a watch face on the ground.

1. Method

solar-declination-by-a-watch-face

Figure: Determining solar declination using a watch face. (The lines SOLAR DECLINATION Its rough estimate is required for Fine Alignment of the watch are to be ignored.)

Draw the dial of an upside-down watch face as a small sub-dial of a watch face (on its 3 o’clock side) as in the figure. The radius of the sub-dial should be close to the length of 4 minutes markings on the rim of the main dial.

The four numbers 6, 9, 12, 3 on the rim of the upside-down sub-dial correspond to 21/6, 23/9, 21/12, 21/3 respectively. They are the dates on the calendar. Your current date gives a point on the rim of this sub-dial.

Project the point of your current date horizontally onto the rim of the main dial. The angle from the direction of 3 o’clock to that of a main long hand pointing to the projected point is equal to the angle of solar declination.

The angles from the Northern and Southern Celestial poles to the Sun are just the angles from the 12 o’clock and 6 o’clock directions respectively to that of the above main long hand.

2. Applications to survival situations

Most multi-dial watches and chronograph watches already have sub-dials made with the sub-dial radius being close to 4 minute length on the rim of the main dial. This method can be conveniently applied to any such watches having their sub-dials on either the 3 o’clock or 9 o’clock side.

When having no actual watch face, you can draw a watch dial and a sub-dial on the ground to determine solar declination.

Accurate value of solar declination improves the accuracy of the determination of North direction using a divider or a watch (references [1], [2]) when the Sun has low altitude in the cold temperate and arctic zones.

References:

[1]. tonytran2015, Finding directions and time using the Sun and a divider., Additional survival tricks, survivaltricks.wordpress.com, https://survivaltricks.wordpress.com/2015/05/06/finding-directions-and-time-using-the-sun-and-a-dividing-compass/, posted on May 6, 2015.

[2]. tonytran2015, Finding accurate directions using a watch, Additional survival tricks, survivaltricks.wordpress.com, https://survivaltricks.wordpress.com/2015/05/19/finding-accurate-directions-using-a-watch/, posted on May 19, 2015.

RELEVANT SURVIVAL blogs

, posted on May 06, 2015 .

wpid-dividermwp3e2c2.jpg

find North by the Sun

Arctic Polar zone view of Equatorial Stars

Navigating with an AM MW radio receiver, posted January 17, 2017, The Scorpius constellation, posted January 8, 2017, The Orion constellation., posted December 26, 2016, Rice as emergency food., Using GPS in off-grid situations, Slide Sky-Disks with grid masks showing azimuths and altitudes, Slide Sky-Map for displaying tropical stars.

Click here for my other blogs on divider43.jpgSURVIVAL

Click here to go to Divider63D400 Home Page (Navigation-Survival-How To-Money).

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Finding accurate directions by a watch .

Method for finding accurate directions by a watch in any latitude.

by tonytran2015 (Melbourne, Australia).

Click here for a full, up to date ORIGINAL ARTICLE and to help fighting the stealing of readers’ traffic.

#find North, #finding North, #compass, #direction, #bisector, #using watch, #with watch, #tilted watch, #inclined watch, #navigation, #without compass

This method uses a watch with analogue face for finding directions. Unlike the traditional method of using the hour hand of a flat lying 24-hour watch, my method uses a 24-hour watch tilted from the vertical and gives better accuracy for both North and South hemispheres including tropical zones. When applied to the arctic and antarctic regions, the watch is tilted by more than 67 degrees and lies almost flat on the ground; it becomes the traditional method using flat lying 24-hour watch.

The method assumes an analogue 24-hour watch is in use. For any analogue 12-hour watch, the bisector between its midnight marking and its 12-hour hand can serve as an imaginary 24-hour hand. From the latitude of the place, the position of the Sun in the sky and the local time shown on the watch, the method gives out the Cardinal directions and declination of the Sun (therefore an estimation of the date and month in the year.

The method for Northern latitudes is described first and is followed by the method for Southern latitudes.

Method for Northern latitudes:

WatchCompass_22NL

A 24-hour watch shown only with hour hand

1/- Hold the watch so that its AXIS rises above the horizontal plane by an angle equal to the latitude of the region. That is its face points to somewhere in the sky and its back is angled downwards into the ground.

2N/- Determine the half-plane limited by the axis of the watch and the backward pointing direction of the 24-hr pointer (the hour hand of the 24hr watch). This half-plane will contain the Sun if this watch displays the local time and the face of the watch and its axis points to the North Star.

3N/-Determine ON THIS SEMI-PLANE a half-line CB from the centre C of its dial, forming with the watch axis an angle equal to the angle between the direction to the Sun and the Northern Star. The half-line CB starts from the centre of the dial and is nearly in the opposite direction of the 24-hour hand (pointer). It rises above the dial toward the glass and points through the glass of the watch during summer time and dives below the dial into the movement compartment of the watch and points through the movement of the watch during winter time. This half-line always points to the Sun if this 24-hr watch displays the local time and the face of the watch and its axis point to the North Star.

4N/- Hold the clock in such composure and rotate your whole body around your vertical axis by your feet until the above half-line CB points towards the Sun (Therefore the Sun lies in the half-plane limited by the watch axis and the backward pointing direction of the 24-hour pointer). At that position, the watch face and its AXIS are POINTING to the North Star.

5/- The projection of the Celestial axis onto the horizontal ground is then the terrestrial Northern-South direction.

The method for determining the North-South direction in the Southern hemisphere is different but is very similar to this method for the North. Paragraphs 2N, 3N and 4N are appropriately replaced by 2S, 3S and 4S for Southern latitudes as in the following.

Method for Southern latitudes:

2S/- The UP-DOWN REFLECTION OF THE HOUR HAND of a 24-hour watch is its imaginary hour hand going anti-clockwise, pointing downwards at midnight and upwards at midday. It is the reflection of the hour hand of a vertically hung 24-hour watch through any water surface below it.

Determine the half-plane limited by the axis of the watch and the up-down reflection of the hour hand. This half-plane will contain the Sun if this 24-hr watch displays the local time and the face of the watch and its axis point to the Southern Celestial pole, while the back of the watch points through the ground to the North Star.

3S/-Determine ON THIS SEMI-PLANE a half-line CB from the centre C of its dial, forming with the watch axis an angle equal to the angle between the direction to the Sun and the Southern Celestial pole. The half-line CB starts from the centre of the dial and is nearly in the direction of the up-down reflection of the 24-hour hand. It rises above the dial toward the glass and points through the glass of the watch during Southern Hemisphere’s summer and dives below the dial into the movement compartment of the watch and points through the movement of the watch during the Southern Hemisphere’s winter. This half-line always points to the Sun if this 24-hr watch displays the local time and the face of the watch and its axis point to the Southern Celestial pole.

4S/- Hold the clock in such composure and rotate your whole body around your vertical axis by your feet until the above half-line CB points towards the Sun (Therefore the Sun lies in the half-plane limited by the watch axis and the up-down reflection of the 24-hour pointer). At that position, the watch face and its AXIS are POINTING to the Southern Celestial pole while the back of the watch points through the ground to the North Star.

No ambiguity in equatorial latitudes.

The watch is placed almost vertically in equatorial latitudes by both methods. Methods for both Northern and Southern latitudes give exactly the same outcomes.

Adaptation for use with any common 12 hr watch.

The method is easily modified for application to any common 12 hr watch. In the following figure, the red hand (the bisector of the 0hr direction and the hour hand of a common 12hr watch ) is in the opposite direction of the hour hand of a 24hr watch.

WatchCompassG

Figure: Summary of finding North by a watch. Red hand is the bisector of 0 hr direction and the hour hand; green hand is its reflection across the (6-12) axis. Axis C-BN for Northern hemisphere is parallel to red hand at equinox days and is (raised above)/(dipped below) the watch dial by 23 degrees at local summer/winter solstice. Axis C-BS for Southern hemisphere is parallel to green hand at equinox days and is (raised above)/(dipped below) the watch dial by 23 degrees at local summer/winter solstice. Green drawing marks are for Southern hemisphere and are the mirror reflection of red drawing marks.

Figure: Summary of finding North by a watch.

Actual field test

The author has tested these methods and found them to be applicable, easy and accurate to within 30 degrees for latitudes from 0 to 40 degrees.

Explanation notes:

N1/- The word “watch” here applies to any watch or clock.

N2/- When a watch or a clock dial is hung on a vertical wall, its midnight marking is at the highest position. If the hour hand of a watch completes one revolution in 24 hours the watch is called a 24-hour watch; if it completes in 12 hour the watch is called a 12-hour watch. Most watches and domestic clocks are 12-hour ones. The bisector of the midnight marking and the hour hand of any 12-hour watch complete one revolution in 24 hour. It moves like an imaginary 24-hour hand on that watch.

N3/-The axis of the watch is the oriented line (Note that it is more than “the oriented half-line”.) going through the centre of the watch at right angle to its dial disc and is parallel to the rotation axes of both the minute pointer (or “minute hand”) and the hour pointer (or “hour hand”). The direction chosen on the line is from the back to the front face of the watch.

N4/- A watch display local time when it shows 12 o’clock when the Sun is highest in the sky.

N5/- The angle between the North Star and the Sun varies like a sine wave with amplitude of 23.5 degrees; it should be 90 degree during Spring and Autumn equinoxes and 90-23.5 degree at Northern Summer solstice (21st June) and 90+23.5 degree at Northern Winter solstice (21st of December).

(Added after December 2016) RELATED SURVIVAL blogs

Finding accurate directions using a watch, posted on May 19, 2015


, posted on 2018 July 10

Find North By Fingers

Finding directions and time using the Sun and a divider., posted on May 6, 2015. <<<—This is my MOST USEFUL novel technique.

wpid-dividermwp3e2c2.jpg

find North by the Sun

Finding North direction and time using the hidden Sun via the Moon . Posted on July 6, 2015

image

Finding North direction and time accurately from the horn line of the Moon. Posted on August 12, 2015. This is my novel technique.

image

Finding North direction and time using the Moon surface features. Posted on July 1, 2015.

image

, posted on

Finding North and time by stars. Posted on August 28, 2015

Sky map Northern 3/4 sphere

Sky map Southern 3/4 sphere

Finding North and time with unclear sky. Posted on October 17, 2015.

image

image

, posted July 22, 2016

DirectionTimeByStars

Click here for my other blogs on divider43.jpgSURVIVAL

divider43.jpg

polymeraust100dollars

Click here go to Divider63D400 Home Page (Navigation-Survival-How To-Money).

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