For 29, 6 days, the moon goes through its full monthly cycle from one new moon to the next. During this time, the relative position of the earth, sun and moon changes, and with it the shape of the illuminated part of the moon visible from the ground changes. The lunar cycle is usually divided into four phases. First, there are two phases of a waxing moon (new moon and first quarter), followed by two phases of a waning moon (full moon and last quarter). Each of the phases lasts approximately 7, 5 days.
Instructions
Step 1
You can visually determine the phase of the moon in our northern hemisphere using mnemonic rules - associations with the outline of letters. If the crescent moon resembles the letter "C", then this is the "Aging" moon, which corresponds to the third and fourth phases of the lunar cycle. It remains only to assess "by eye" what proportion of this natural satellite remained illuminated - if more than a quarter, then this is the third phase, and if less - the fourth. If the lunar crescent is turned in the opposite direction and you can mentally add a vertical line to it to get the letter "P" - then this is the "Growing" moon, which corresponds to the first and second phases of the cycle. If the visible part is less than a quarter of the disc, then this is the first quarter, if more - the second.
Step 2
If you need a more precise definition or you need to find out the phase of the moon on any particular day in history, then you can use the Internet resources that provide such a service. For example, on the website redday.ru/moon, in order to find out the phase of the moon for a certain day, you need to set the values you need in the drop-down lists of the day, week and year. Here you can also set the time to the nearest minute. Then select the city you are interested in from the drop-down list of cities. There is also a checkbox that sets the correction for "daylight saving" time. By installing everything and clicking the button labeled "Show", you will receive a picture corresponding to the phase of the moon on a given day, data on the current quarter of the moon for that day, as well as the date and time of the beginning of this phase, the ordinal number of the day in the lunar month ("age" moon), the percentage of the visible surface and a lot of information characterizing the lunar phase of the desired day.
Step 3
There are also application programs that can be found on the network and installed on a computer if you need to find out the phases of the moon quite often. For example TNR MoonLight, Moon Calendar CE, Desktop Lunar Calendar, etc.
