Note that crescent strictly means "growing"; the Moon should really be called decrescent at this phase. If you know how many days it is since New Moon, multiply that by 50 minutes, to find out approximately how much the Moon is lagging behind the Sun. It will only be approximate, because the Moon's orbit is an ellipse rather than a circle, and it doesn't go round at a constant speed.
So the Moon crosses the sky about 50 minutes later every day. And you might think it would rise 50 minutes later every day, and set 50 minutes later too. But this isn't true - because the Moon doesn't spend the same length of time above the horizon every day.
The Sun goes through a seasonal variation, once a year. In December and January, the Sun is in the far south of the sky. It rises in the south-east; it spends only a few hours above the horizon for northern-hemisphere observers , crossing the sky quite low down; and it sets in the south-west. In June and July, the Sun is in the far north of the sky. It rises in the north-east ; it spends many hours above the horizon for northern-hemisphere observers , crossing the sky quite high up; and it sets in the north-west.
The Moon follows the same cycle, but about twelve times faster; it gets round in about a month. What I have trouble grasping is how this takes place in only a months time? Does the Earth have a month-long wobble, or what?
While in the question you mention that you understand why the Sunrise and Sunset positions change, let me start there and then move onto the Moon, because the explanation is somewhat connected, and is related to the geometry of the orbits and rotations in the Earth-Moon-Sun system. The Earth rotates counter-clockwise on its axis picture a spinning top. The Moon phase simulation does not take into account the actual visibility of the Moon from the selected location.
The Moon may currently be below the horizon , or adverse weather conditions may prevent a Moon sighting. This means that they do not correctly represent the Moon phases in the Southern Hemisphere, where the illuminated portion of the lunar surface moves from left to right instead of right to left. However, rather than showing what the phases actually look like in the selected city, they are static symbols designed to provide a simplified representation of each phase.
The see a dynamic, real-time representation of the current Moon phase in the selected city, please see the Moon phase simulation near the top of the page instead. To keep the chronological order of events. On some days, the Moon sets at an earlier time of day than it rises. When this happens, the Moonrise column, if we only had one, would show a later time than the Moonset column , which would be counter-intuitive with regards to the normal reading direction from left to right.
On some days, the Moon does not rise or set. Because the Moon is constantly in motion , the time span from one moonrise or moonset to the next is a little longer than 24 hours. For example, if the Moon rises just before midnight on day 1, it may not rise again until just after midnight on day 3, meaning that day 2 does not have a moonrise. To change the format, please go to My Units and make a selection in the Time Format drop-down, and click Save Settings. To use our new map location picker, click on the search field and then on Open Map.
To choose your location, click on the map and click Select. Clicking Cancel closes the window. You can use the search field to find your location, and then refine it by clicking on the map to get closer to your desired location. Clicking the target icon will take you to the location you have customized in the settings. We appreciate your feedback! The map location picker is a BETA service, so it is still under development. If you find anything wrong or have suggestions to improve it, please let us know.
Our database of locations includes thousands of cities worldwide, and we now offer an additional 6 million places via the GeoNames database. If you still don't find your town, please let us know , and we will consider adding it.
When you type the location into the search field and it suggests several places by the same name, first have a look at the country flag and the description in parentheses to identify the city you are looking for. Both moonrise and moonset are defined as the moments when the upper edge of the Moon's disk touches the horizon. The table under Moonrise, Moonset, and Phase Calendar for To switch to a different month, use the drop-down menus above the table or the links below the table.
Yes, you can look up any location by entering geographic coordinates latitude and longitude into the search field. You can look up any location on Earth by entering geographic coordinates latitude and longitude into the search field.
Yes, all Moon times take into account the fact that the Earth's atmosphere refracts the incoming light from the Moon in such a way that the Moon is visible longer than it would be without an atmosphere.
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