Blog image of Contents of Survival sub-page

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.

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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

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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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Finding North direction and time by any bright star.

NorthByKnownStar

Finding North direction and time by any bright star

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, #find, #direction, #time, #bright star, #Sun, #divider, #navigation.

Find North Direction and time by any bright star.

Most people living in the Northern temperate and arctic zones know how to find the star Polaris to find North direction and can even tell time by the orientation of the Little Dipper (part of the Little Bear). But Polaris is not an easily seen bright star and may even be hidden from view for people in Tropical zone and in Southern Hemisphere.

This posting shows how to use ANY arbitrarily known star to find North direction and time, and is useful to non-users of Polaris star. The method is similar to that given previously using the Sun [1] and is useful when only one bright star is visible in an unclear sky (affected by thick clouds or pollution).

The divider compass in this posting is only for instructional purpose and is not needed in actual application. The user may use any two of his fingers instead.

1. Requirements by the method.

To apply this method you need:
1. Your current latitude,

2. The current date in the Solar Year,

3. An unmistable bright star,

4. Its Declination and its Right Ascention already converted to Date of that Star in the Solar Year (see the details on the Conversion in the following section).

2. The date of a star.

BrightStars20Plus2

Figure: Table of bright stars with their approximate dates .

The date of a star should be known, even only approximately by the month, if the user wants to tell time from that star.

The date is obtained from the linear conversion:

a. 00:00 hr of R.A. —-> Sep 23 in Date

b. 06:00 hr of R.A. —-> Dec 21 in Date

c. 12:00 hr of R.A. —-> Mar 21 in Date

d. 18:00 hr of R.A. —-> Jun 21 in Date
Any star is visible nightly (either from Sunset to its setting or from its rising to Sunrise) for more than 9 months each year. The visibility cycle for each star begins with the star seen rising near the Eastern horizon few minutes before Sunrise. On subsequent days, the star rises earlier and earlier, it travels gradually towards the West and remains for longer and longer duration in the night sky until one day it stays for the whole night. The star is therefore called a star of that date. After that day, the star is seen setting in the West in the night. On subsequent days, its lead on the Sun gradually increases and it sets on the West at earlier and earlier time. Near the end of the cycle, the star is visible above the Western horizon for only few minutes after Sunset. It then sets on the West. At the end of this cycle, the star is too close to the Sun to be visible in the sky. The cycle then repeats from the beginning.

Example:

Boote Arcturus is a star of April 25th with declination 19 degree N. Step 6 of reference [2] shows how to easily identify it.

It reaches its highest elevation at mid-night of that date and remain visible for that whole night.

In February it rises about 4 hr after Sunset and has not enough time to complete the journey to the West. On April 25th it rises at about Sunset to complete the journey to the West about Sunrise. In June it is seen already high in the sky at Sunset and set on the West 4 hr before Sunrise.

3. Selecting a star for current month in the year.

PolrNorthNC20const8

Figure: Sky map (Inversion type) of the Northern Celestial 3/4-sphere showing only 20 brightest stars and some constellations.

polrsouthq3c60.jpg

Figure: Sky map (Inversion type) of the Northern Celestial 3/4-sphere showing only 20 brightest stars and some constellations.

Select a bright star of a date in the year near to your current date (or month) and read its declination from any source such as the internet, your own tables or the two star maps supplied here. If you use the star maps, its declination is read from the constant declination circles and its date from the rim on the opposite side (that is also the point closest to the Sun on the elliptic circle).

This method requires POSITIVE IDENTIFICATION of your chosen star. To positively identify it, you may need to see

1/- either neighbouring bright stars, their relative distances and orientation

2/- or surrounding dimmer stars making up the constellation containing it.

When that star is the only visible one in the sky you may have to identify it relying on its appearance details in previous nights such as:

1/- Continuity of its characteristics from previous nights (or hours),

2/- its elevation after Sunset,

3/- its relative directions from the setting Sun or the (moving) Moon,

4/- its ranking as the few brightest objects in the sky after Sunset.

Stars near to the elliptic may sometimes be confused with much brighter planets and their use involves extra cares.

If you are away from the two polar zones and always can see an unobstructed sky (nearly half of the Celestial sphere), you only need to find one of the 3 stars Orion Rigel, Boote Arcturus and Altair to apply this method.

4. Rules for turning to lower Celestial pole.

divider43.jpg

Figure: The rule for finding North by any chosen star is similar to the rule illustrated here for the Sun.

Be certain of your hemisphere and whether the star is rising (early star) or setting (late star) to turn the second leg of the divider to the left or to the right. This is similar to the requirement for finding North using the Sun.

Then apply all the steps of the next section.

5. Steps to find North direction and time using a star.

DirectionTimeByStars

Figures: Summary of steps to find North direction and time by any known star.

When any star is used on its date in the year, the Sun leads it by exactly 12 hours. For every month after that, the lead by the Sun is reduced by 2 hours (or every 12 months by 24 hours). The last figure of the illustration shows the Sun leading the star by about 5 hours on the Celestial clock face.

Example 1:

In December, January, February use Sirius if you can see it.

Sirius is a star of Jan 1st with declination 17 degree S. Step 8 of reference [2] shows how to find it.

On Jan 1st the time determined by Sirius is 12 hours behind the time by the Sun.

On April 1st, the time determined by Sirius is 6 (=12-3*2) hours behind the time by the Sun.

Example 2:

In March, April, May use Boote Arcturus if you can see it.

Boote Arcturus is a star of April 25th with declination 19 degree N. Step 6 of reference [2] shows how to identify it.

On April 25th the time determined by Boote Arcturus is 12 hours behind the time by the Sun.

On May 25th, the time determined by Boote Arcturus is 10 (=12-1*2) hours behind the time by the Sun.

On June 25th, the time determined by Boote Arcturus is 8 (=12-2*2) hours behind the time by the Sun.

References.

[1]. tonytran2015, Finding directions and time using the Sun and a divider., survivaltricks.wordpress.com, posted on May 6, 2015.

[2]. tonytran2015, Finding North and time by stars, survivaltricks.wordpress.com, posted on August 28, 2015.

RELEVANT SURVIVAL blogs (Added after February, 2017)

Caution in finding North by bisector line of a horizontal watch. Posted on October 28, 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

 

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 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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