MoonPhase
gives moon phase fraction of illumination for the current date.
MoonPhase[datespec]
gives moon phase fraction of illumination for the specified date.
MoonPhase[property]
gives the property of the moon phase for the current date.
MoonPhase[datespec,property]
gives the property of the moon phase for the specified date.
Details
![](Files/MoonPhase.en/details_1.png)
- The phase of the Moon, also known as the lunar phase, describes the fraction of the lunar surface illuminated by the Sun as seen from Earth.
- MoonPhase[] makes use of $TimeZone to determine your time zone.
- datespec can be a DateObject expression, a TimeObject expression, a date string or a {y,m,d,h,m,s} date list.
- datespec is assumed to be in $TimeZone, unless it is a DateObject or TimeObject expression with an explicit TimeZone option value.
- If datespec is a list of dates, then the results will contain EventSeries or TimeSeries objects.
- datespec can be specified as {start,end,increment} for compatibility with DateRange specifications.
- MoonPhase["Fraction"] is equivalent to MoonPhase[].
- MoonPhase can accept the following values for property:
-
"Fraction" fraction of illumination "SignedFraction" signed fraction of illumination "Name" name of the moon phase "Icon" icon representing the moon phase
![](Files/MoonPhase.en/Image_1.gif)
Examples
open allclose allBasic Examples (4)
Scope (7)
Dates can be specified as a DateObject:
Generalizations & Extensions (1)
IconData can accept the signed fraction of the moon phase as its second argument:
Possible Issues (1)
The names of moon phases are based on the illumination fraction value. On a given day, the name of the moon phase may change, depending on what time it is. For example, a full moon does not last a full day, so even if a full moon occurs on that day, you may have to change the time in order to get the phase you might expect:
Text
Wolfram Research (2014), MoonPhase, Wolfram Language function, https://reference.wolfram.com/language/ref/MoonPhase.html.
CMS
Wolfram Language. 2014. "MoonPhase." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/MoonPhase.html.
APA
Wolfram Language. (2014). MoonPhase. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/MoonPhase.html