In a recent survey, the majority of people questioned were surprised to learn that astro navigation can be used in a survival situation. In the same survey, 60% said that they would use satellite navigation systems to find their way if they were lost and that they wouldn’t know what to do if they did not have access to such equipment.
There are two types of survival situation in which astro navigation can be used to help people to establish their position and these are ‘Survival at Sea’ and what we term as ‘Wilderness Survival’.
Survival at sea. The simple astro navigation techniques listed below could be used by survivors in the following circumstances:
- In mid ocean, adrift in a lifeboat without GPS.
- In mid ocean, suffering electrical failure resulting in loss of radio, radar, and global posistioning system (GPS) but unable to use full astro navigation techniques .
- In mid ocean, unable to use full astro navigation techniques but experiencing long term failure of GPS system .
Wilderness survival The simple astro navigation techniques listed below could be used by the following types of survivor assuming that they are lost in a wilderness and have no access to GPS or a mobile phone.
- Aircraft crash survivor.
- Shipwreck survivor.
- Military personnel in ‘escape and evasion’ situation in a war zone.
- Escapee from prisoner of war camp in a war zone.
- Refugee from a war zone.
Frequently asked questions
- How likely is it that GPS could fail? Click here for a full answer to this question.
- How many war zones are there? There have been over 150 major and minor wars since 1945. There are currently 10 major wars taking place and 32 civil wars.
- What is a wilderness? There are many definitions of a wilderness but the one commonly accepted is: ‘A wild place that is sparsley inhabited, is not developed with towns, roads, any form of industrial infrastructure and has no form of electronic communications system’.
Astro Navigation methods that could be used in survival situations.
There are three methods that could be used in a survival situation as follows:
- Finding your latitude from the North Star (Polaris).
- Finding your latitude from the midday Sun.
- Finding your longitude from the time that the Sun reaches its highest altitude.
Fixing your geographical position in lat.and long.at midday. By measuring the Sun’s altitude at midday, your geographical position in terms of latitude and longitude can be calculated by using methods 2 and 3 above.
Equipment needed for the above methods. Only the following very basic equipment is needed to use these methods:
- A home-made mini clinometer for measuring angles. Go to this page to learn how to make one.
- A piece of smoked glass to be used so that the altitude of the Sun can be measured without damaging a person’s eyesight. (If a piece of manufactured smoked glass cannot be obtained, simply hold a piece of glass in the smoke of a candle or oil lamp until it is covered in a layer of smoke residue).
- A watch, set to GMT (this is only required for method 3).
- Declination table. (this is only needed for method 2). Go to declination table. (Note. A sea going vessel with a current nautical almanac would not need this declination table).
- A magnetic compass (not essential for these methods).
Be prepared. It is recommended that you prepare the above equipment and store it in your rucksack in case it is needed in a wilderness survival situation or store it in your boat ‘grab’ bag in case it is needed in a survival at sea situation.