The tip-to-tip span between your index finger and your little finger is 15°.The tip of your little finger and your thumb will span about 25°. Open up your fist, stretch your little finger and thumb as far as you can and curl down the rest of your fingers.This means that angular distance or angular separation between the two stars is 30°. The North Star (Polaris) and Dubhe, one of the northern pointers of the Big Dipper are 3 fists apart. This means that any two objects that are on the opposite ends of your fist will be 10 degrees apart. The width of your fist will approximately be 10 degrees. Make a fist, with the back of your hand facing you.Hold your hand at arm’s length and close one eye. The zenith is always 90° from the horizon. The point right above you in the sky is the zenith. The other half of the celestial sphere is below the horizon and cannot be seen. If you look above at the sky, you will see only half of the sky i.e. Imagine the sky as a big hollow sphere with the Earth at its center – let’s call this the celestial sphere.
There are 360° in a circle or sphere, each degree is divided into 60' and each arc minute is further divided into 60". Like our modern-day timekeeping, the angular method is based on a sexagesimal system – a numeral system with 60 as its base. While angular separation primarily describes the apparent distance between celestial objects, as seen from Earth, it can also be used to suggest their actual distance from one another. Known as angular distances or angular separation, distances are expressed in terms of degrees (°), arc minutes ('), and arc seconds ("). Measuring Anglesīecause of this, astronomers measure the distance between celestial objects based on the angle they make with an observational point on Earth. Our conventional methods of measuring distances between two objects on Earth make very little sense when measuring the vast distances between celestial objects. Business Date to Date (exclude holidays)Ī handy way to measure distances in the sky.It is nice to know you have the knowledge to make educated decisions dealing with time, even when you do not have a working watch. Or how much time you have to return home.Ĭellphone batteries die quickly when you are out of range of cell towers or have only one bar. Using this method you can easily calculate how much time you have to finish up your task. This means that each finger represents 15 minutes. Each hand width is about 1 hour of daylight left. Simply extend your arm fully and count the number of hand widths between the sun and your apparent horizon. And actually knowing when the sun sets there isn't as much of an issue because during the summers the sun will be traveling at such and angle that daylight isn't fully lost nearly as quickly.įor those of us that live in the continental USA or any place worldwide that is closer to the equator than Canada or Alaska, you can easily estimate how long until the sun sets using only your hand. The only places it becomes less accurate is near the poles. This method is simple, easy and most importantly accurate for most places. Well, there is a really easy method for letting you know how much daylight you have left. It also does not take into account things such as trees and mountains blocking your theoretical horizon. Sure you can look at a watch, but that requires you to know exactly when the official sunset is. When in the wild, away from civilization knowing how long until dark can be a life saver.
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