AstroRiseSet

returns the dates of the next rising and next setting of the astronomical body astro.

returns the date of the next event of type etype, such as "Rise" or "UpperCulmination", for the given body astro, as observed from the current geo location.

AstroRiseSet[astro,etype,loc]

returns the date of the next event of type etype for the given body astro, as observed from location loc.

AstroRiseSet[astro,etype,loc,date]

returns the date of the next event of type etype after the given date.

Details and Options

AstroRiseSet computes the instant when any celestial object, like the Sun, the Moon or a star, crosses the local horizon or the local meridian at the given location. This can be a location on Earth or any other celestial body in the solar system.

Possible event types etype in AstroRiseSet[astro,etype,…] include:

	"Rise"	the body astro crosses the horizon upward, in the east
	"Set"	the body astro crosses the horizon downward, in the west
	"UpperCulmination"	the body astro crosses the local meridian at its highest altitude
	"LowerCulmination"	the body astro crosses the local meridian at its lowest altitude

AstroRiseSet[astro,{etype₁,etype₂,…},…] returns a list of pairs dateetype_i of the next events of the given types, sorted by dates.
The astro in AstroRiseSet[astro,…] can be specified as an entity of any astro domain, or a string that unambiguously defines that entity. Named directions such as "TrueEquinox" or "NorthGalacticPole" are also accepted.
Locations loc in AstroRiseSet[astro,etype,loc,…] can be specified as geo entities or explicit GeoPosition[{lat,lon}] or GeoPosition[{lat,lon},planet] objects. Elevation h, specified as GeoPosition[{lat,lon,h}], affects the times of rising and setting of celestial objects.
AstroRiseSet[astro,etype,loc,dint] for a DateInterval object dint returns a list of all events of the given type that can be observed during that interval. The notation {date₁,date₂,All} is equivalent to DateInterval[{date₁,date₂}].
AstroRiseSet[astro,etype,loc,{date₁,date₂,…}] returns an EventSeries collection of pairs {date_i,AstroRiseSet[astro,etype,loc,date_i]}.
Options of AstroRiseSet include:

CalendarType	Automatic	calendar used to return dates
DateFormat	Automatic	format used to display output dates
DateGranularity	Automatic	calendar granularity of output dates
ReferenceAltitude	Automatic	altitude value defining the instant of rise/set
TimeDirection	1	whether to return the next or last new moon
TimeSystem	Automatic	time system of output dates
TimeZone	$TimeZone	time zone of output dates

Possible values of the ReferenceAltitude option include:

	Automatic	upper limb of the body crosses zero altitude
	alt	center of the body crosses numeric altitude alt
	{alt,limb}	the given limb of the body crosses numeric altitude alt

The reference altitude angle alt can be given as a Quantity angle or as a numeric expression interpreted in angular degrees. For the particular case of the Sun, these are the traditional values of reference altitude:

	"Civil"	the center of the Sun has altitude –6 degrees
	"Nautical"	the center of the Sun has altitude –12 degrees
	"Astronomical"	the center of the Sun has altitude –18 degrees

Possible values for the limb of the body include:

	"UpperLimb"	upper limb of the body
	"Center"	central point of the body
	"LowerLimb"	lower limb of the body
	limb	numeric value between –1 (lower limb) and 1 (upper limb)

Examples

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Basic Examples (4)

Find the next rising of Mars, as observed from your geo location:

Find the times of setting of the Moon this week as observed from Chicago:

The difference between consecutive days is always more than 24 hours:

Find the times of civil and astronomical twilight today:

There are no sunrises in long periods of summer or winter in a location beyond the polar circle:

Scope (11)

Observed Astronomical Objects (2)

Compute the next rise and set times for any type of astronomical object, as observed from your location:

Compute rise and set times for named directions in space:

Event Types (2)

Compute the next rise and set instants for Jupiter:

Compute both simultaneously, sorting by date:

Compute culmination instants for Jupiter:

Compute both simultaneously, sorting by date:

Observation Locations (3)

Specify the location of observation:

Observe the moon Phobos from a location on Mars:

Most objects in the solar system can also be denoted using strings:

Compute rise events for a list of locations:

Each change of 30 degrees in longitude corresponds to about 2 hours of difference, modulo one day:

Observation Dates (4)

Find the next rise event for Mars from your current geo location:

Find the first rise event for Mars in the year 2025 from your current geo location:

Find all rise events for Mars in the first seven days of year 2025:

This can also be specified as follows:

Find the collection of events after a given list of dates in year 2024:

The result is given as an EventSeries expression:

Use Normal to get the corresponding list of pairs of dates:

Options (8)

CalendarType (1)

AstroRiseSet returns dates in the Gregorian calendar by default:

Return dates in the Jewish calendar:

DateFormat (1)

AstroRiseSet returns dates in a long format by default:

Specify your own format:

DateGranularity (1)

AstroRiseSet returns dates with granularity "Instant" by default:

Return dates with "Day" granularity:

ReferenceAltitude (2)

By default, AstroRiseSet reports rise and set instants when the upper limb of the body has altitude zero:

Therefore, the actual center of the body is below the horizon:

Use a specific value of altitude and choice of limb:

Find the next date of sunrise, by default using the horizon and the upper limb of the Sun:

Use the same horizon at zero apparent altitude, but now comparing to the center of the Sun:

Find the starting time of civil, nautical and astronomical twilight, all defined by the center of the Sun:

TimeDirection (1)

AstroRiseSet finds the next event of the given type by default:

Find the previous event:

TimeSystem (1)

AstroRiseSet returns dates in universal time by default:

Return dates in "TT" time instead:

TimeZone (1)

AstroRiseSet returns dates in your local time zone by default:

Return dates in the GMT time zone:

Applications (7)

Visualize rise and set events using TimelinePlot:

Compute sunrise and sunset dates during the year 2024 for your current geo location and local time zone:

Separate them in two groups of rises and sets:

Plot the dates for the whole year:

Plot the corresponding times of day over the year, showing daylight saving shifts:

Compute sunrise and sunset times for a location of high latitude, using a fixed time zone:

Extract the time part of each sunrise and sunset date:

Compute and plot the times of moonrise and moonset during May 2024 for your current geo location:

Extract the time part of each sunrise and sunset date:

Show how the upper limb of the Sun touches the horizon at the times of rise and set:

Show how the upper limb of Venus touches the horizon at the times of rise and set:

Find the times of setting of the Moon this month as observed from London:

The difference between consecutive days can vary between 24h 17min and 25h 24min:

Properties & Relations (8)

Polaris is always visible from Chicago, so it does not rise and set:

However, it can never be observed from locations in the Southern Hemisphere:

Compute the instant of upper culmination (also known as meridian upper transit) of the Sun:

That instant defines "solar noon":

The Sun has azimuth 180 degrees:

Compute the instant of lower culmination (also known as meridian lower transit) of the Sun:

That instant defines "solar midnight":

The Sun has azimuth 0 degrees, or equivalently 360 degrees:

The Moon may not rise or set during a given day:

This was the sequence of events during three days:

The Moon may have three rise/set events in the same day:

Plot the elevation of the Moon during that day:

Sunrise[loc,date] is equivalent to AstroRiseSet["Sun","Rise",loc,date]:

Sunset[loc,date] is equivalent to AstroRiseSet["Sun","Set",loc,date]:

When the upper limb of a body touches the horizon, its center has a small negative altitude:

Specify that rise and set are defined with respect to the center of the object:

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