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Ho many hours until sunset
Ho many hours until sunset












ho many hours until sunset

Wherever you are you will need to know your approximate latitude.So with the above information it now becomes quite straightforward to accurately assess how much daylight you have left. So for London which is 51✣0′ North the angle the suns sets at will be 90º – 51✣0′ = 38✣0′ In fact the exact angle can be calculated if you know your latitude, simply take away your latitude, north or south of the equator from 90 degrees and this will give you the angle with the horizon made by the trajectory of the setting sun.

ho many hours until sunset

As you move away from the tropics towards the poles the angle of the sun to the horizon as it sets (and rises for that matter) gets shallower and shallower. Which is why in the tropics it seems to go from day light to darkness very quickly. Between the tropics of Cancer and Capricorn the sun will set close to perpendicular to the horizon, that is is sets almost straight down. The next factor we need to consider is the angle that the sun actually sets at. If a whole fist which is equivalent to 5 fingers only marks out 10 degrees of the sun’s movement, equivalent to 40 minutes of time how can each finger equate to 15 minutes? The simplest and easiest one to remember is that an outstretched fist will mark out approximately 10 degrees…………so straight away you should be able to start seeing a problem. There are several recognised methods for estimating different angles using your out-stretched hand.

#Ho many hours until sunset full#

This can simply be calculated by dividing 360 degrees (one full rotation) by the number of hours i.e. But don’t just take my word for it, below is the science and maths behind what is actually happening that will allow you to judge the amount of daylight you have left far more accurately wherever you are on the planet.įirstly, the sun appears to move through the sky at a constant rate due to the earth making one complete revolution every 24 hours. There are only two latitudes, one north and one south of the equator where it would actually work reasonably accurately and they are not at what I would call a mid-latitudes. The reality is, that, if not completely wrong it is inaccurate and therefore could be potentially dangerous. It is also referenced in a some books including the “Collins Ultimate Navigational Manual” and the book “Show Me How” from where the following image is duplicated on many of the websites. Sometimes, admittedly, the website will say that this is approximate or an estimate and one or two mention that it only works at certain latitudes (they quote mid latitudes…….a bit vague!!).

ho many hours until sunset ho many hours until sunset

Type “using your fingers to estimate sunset” into your favourite search engine and dozens of websites will all tell you how that if you hold your hand out at arms length and line up the bottom of your little finger with the horizon the number of fingers that will fit between the horizon and the bottom of the sun can be used to calculate the time until the sun sets, which is normally quoted as 15 minutes per finger. One that has been perpetuated for many years and seems to regularly do the rounds on social media, is, using your fingers to estimate how long you have got until the sun sets. As I’m sure happens with pretty much every subject, bushcraft and survival contains its fair share of “urban myths”.














Ho many hours until sunset