mint/app/calendar

SunCalc

SunCalc is a tiny BSD-licensed JavaScript library for calculating sun position, sunlight phases (times for sunrise, sunset, dusk, etc.), moon position and lunar phase for the given location and time, created by Vladimir Agafonkin (@mourner) as a part of the SunCalc.net project.

Most calculations are based on the formulas given in the excellent Astronomy Answers articles about position of the sun and the planets. You can read about different twilight phases calculated by SunCalc in the Twilight article on Wikipedia.

Usage example

// get today's sunlight times for London
// 获取当天伦敦的太阳时间参数
var times = SunCalc.getTimes(new Date(), 51.5, -0.1);// 经度，纬度 

// format sunrise time from the Date object
// 从Date对象格式化日出时间 hh:mm
var sunriseStr = times.sunrise.getHours() + ':' + times.sunrise.getMinutes();

// get position of the sun (azimuth and altitude) at today's sunrise
// 获取今天日出时太阳的位置（当地经度，当地纬度）
var sunrisePos = SunCalc.getPosition(times.sunrise, 51.5, -0.1);

// get sunrise azimuth in degrees
// 得到太阳方位角
var sunriseAzimuth = sunrisePos.azimuth * 180 / Math.PI;

SunCalc is also available as an NPM package: SunCalc也可以作为NPM软件包提供：

$ npm install suncalc

var SunCalc = require('suncalc');

Reference调用

Sunlight times 太阳时间

SunCalc.getTimes(/*Date*/ date, /*Number*/ latitude, /*Number*/ longitude, /*Number (default=0)*/ height)
SunCalc.getTimes(/*日期*/ date, /*纬度*/ latitude, /*经度*/ longitude, /*海拔高度（千米） (default=0)*/ height)

Returns an object with the following properties (each is a Date object):

返回一个对象具有一下属性（每一个都是一个Date对象）

Property属性	Description描述
sunrise	sunrise 日出(top edge of the sun appears on the horizon 日轮上缘出现在地平线)
sunriseEnd	sunrise ends 日出结束(bottom edge of the sun touches the horizon 日轮下缘触及地平线)
goldenHourEnd	朝霞结束morning golden hour (soft light, best time for photography) ends
solarNoon	正午solar noon (sun is in the highest position 太阳位于高度角达到最高)
goldenHour	evening golden hour starts 晚霞开始
sunsetStart	sunset starts 日落开始 (bottom edge of the sun touches the horizon 日轮下缘触及地平线)
sunset	sunset 日落(sun disappears below the horizon, evening civil twilight starts日轮上缘消失在地平线，夜幕降临)
dusk	dusk 暮色 (evening nautical twilight starts 航海夜幕开始)
nauticalDusk	nautical dusk 航海暮色 (evening astronomical twilight starts 天文夜幕开始)
night	night starts 入夜 (dark enough for astronomical observations夜色足够黑暗可以进行天文学观察)
nadir	nadir天底 (darkest moment of the night, sun is in the lowest position 夜晚的至暗之时，太阳位于最低点)
nightEnd	night ends夜尽 (morning astronomical twilight starts 天文曙光开始)
nauticalDawn	nautical dawn 航海曙光 (morning nautical twilight starts 航海曙光开始)
dawn	dawn 破晓(morning nautical twilight ends, morning civil twilight starts航海曙光结束，民用曙光开始)

SunCalc.addTime(/*Number*/ angleInDegrees, /*String*/ morningName, /*String*/ eveningName)

Adds a custom time when the sun reaches the given angle to results returned by SunCalc.getTimes.

当太阳到达给定角度时，通过SunCalc.getTimes将自定义时间添加到返回的结果中。

SunCalc.times property contains all currently defined times. SunCalc.times属性包含了所有当前已定义的时间

Sun position太阳位置

SunCalc.getPosition(/*Date*/ timeAndDate, /*Number*/ latitude, /*Number*/ longitude)

Returns an object with the following properties:

• altitude: sun altitude above the horizon in radians,太阳高度（以弧度为单位） e.g. 0 at the horizon and PI/2 at the zenith (straight over your head) 0为地平线 PI/2为天顶
• azimuth: sun azimuth in radians (direction along the horizon, measured from south to west),太阳弧度（以弧度为单位）（地平线的投影方向，从南到西测量）， e.g. 0 is south and Math.PI * 3/4 is northwest
• 0为正南
• Math.PI * 1/4为西南
• Math.PI * 1/2为正西
• Math.PI * 3/4 西北
• Math.PI 为正北

Moon position

SunCalc.getMoonPosition(/*Date*/ timeAndDate, /*Number*/ latitude, /*Number*/ longitude)

Returns an object with the following properties:

• altitude: moon altitude above the horizon in radians 月亮高度（弧度）
• azimuth: moon azimuth in radians 月亮水平偏移（弧度）
• distance: distance to moon in kilometers 地月距离（千米）
• parallacticAngle: parallactic angle of the moon in radians 月亮的视差角（弧度）

Moon illumination月轮亮度

SunCalc.getMoonIllumination(/*Date*/ timeAndDate)

Returns an object with the following properties: 返回一个具有以下属性的对象

• fraction: illuminated fraction of the moon; varies from 0.0 (new moon) to 1.0 (full moon)
• 月亮照亮的部分，从0.0到1.0变化
• phase: moon phase; varies from 0.0 to 1.0, described below
• 月相；从0.0到1.0变化，描述如下
• angle: midpoint angle in radians of the illuminated limb of the moon reckoned eastward from the north point of the disk; the moon is waxing if the angle is negative, and waning if positive
• 通过月亮照亮的部分从圆盘的正北向东偏移的角度（以弧度计）的中点；如果角度为负，则月亮在变亮；如果角度为正，则月亮在变暗

Moon phase value should be interpreted like this: 月相值的解释如下：

Phase相	Name
0	New Moon 新月
	Waxing Crescent 凹月渐亮
0.25	First Quarter 上弦月
	Waxing Gibbous 凸月渐满
0.5	Full Moon 满月
	Waning Gibbous 满月渐小
0.75	Last Quarter 下弦月
	Waning Crescent 凹月渐暗

By subtracting the parallacticAngle from the angle one can get the zenith angle of the moons bright limb (anticlockwise). The zenith angle can be used do draw the moon shape from the observers perspective (e.g. moon lying on its back).

Moon rise and set times

SunCalc.getMoonTimes(/*Date*/ date, /*Number*/ latitude, /*Number*/ longitude[, inUTC])

Returns an object with the following properties:

• rise: moonrise time as Date
• set: moonset time as Date
• alwaysUp: true if the moon never rises/sets and is always above the horizon during the day
• alwaysDown: true if the moon is always below the horizon

By default, it will search for moon rise and set during local user's day (frou 0 to 24 hours). If inUTC is set to true, it will instead search the specified date from 0 to 24 UTC hours.

Changelog

1.8.0 — Dec 22, 2016

• Improved precision of moonrise/moonset calculations.
• Added parallacticAngle calculation to getMoonPosition.
• Default to today's date in getMoonIllumination.
• Fixed incompatibility when using Browserify/Webpack together with a global AMD loader.

1.7.0 — Nov 11, 2015

• Added inUTC argument to getMoonTimes.

1.6.0 — Oct 27, 2014

• Added SunCalc.getMoonTimes for calculating moon rise and set times.

1.5.1 — May 16, 2014

• Exposed SunCalc.times property with defined daylight times.
• Slightly improved SunCalc.getTimes performance.

1.4.0 — Apr 10, 2014

• Added phase to SunCalc.getMoonIllumination results (moon phase).
• Switched from mocha to tape for tests.

1.3.0 — Feb 21, 2014

• Added SunCalc.getMoonIllumination (in place of getMoonFraction) that returns an object with fraction and angle (angle of illuminated limb of the moon).

1.2.0 — Mar 07, 2013

• Added SunCalc.getMoonFraction function that returns illuminated fraction of the moon.

1.1.0 — Mar 06, 2013

• Added SunCalc.getMoonPosition function.
• Added nadir (darkest time of the day, middle of the night).
• Added tests.

1.0.0 — Dec 07, 2011

• Published to NPM.
• Added SunCalc.addTime function.

0.0.0 — Aug 25, 2011

• First commit.