b612
16c62a97d5
- 新增时标、ΔT 模型、质心时间与 UT1 支持 - 改进日月食、月掩、行星事件及路径边界计算 - 完善恒星三维自行与动态距离传播 - 扩展 SVG、GeoJSON、KML 输出与底层距离换算工具 - 整理中英文手册、示例资源及回归测试
533 lines
21 KiB
Go
533 lines
21 KiB
Go
package eclipse
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import (
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"math"
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"time"
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"b612.me/astro/basic"
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)
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const (
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lunarEclipseSynodicMonthDays = 29.530588853
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lunarEclipseSearchLimit = 24
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lunarEclipseSearchEpsilonDay = 1e-8
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// 默认口径仍以 Danjon 为主，但对五千年目录边界那类“Danjon 判无食、Chauvenet 判极浅半影食”的个例，
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// 允许在公开默认包装层回退到 Chauvenet，避免把目录中确有记录的边缘半影食整个跳过。
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lunarEclipseDefaultFallbackMaxPenumbralMagnitude = 0.03
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// 当天判断的第一层只做粗筛：
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// 如果本地中午的日月黄经差明显不在满月附近，则这一天不可能发生月食。
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lunarEclipseDayPhaseMin = 120.0
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lunarEclipseDayPhaseMax = 240.0
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// 月食只会发生在月球接近黄道节点时。
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// 这里保守放宽到 2 度，作为“是否值得进入精算”的预筛条件。
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lunarEclipseLatitudeLimitDeg = 2.0
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lunarEclipseLongitudeLimitDeg = 15.0
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)
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type lunarEclipseCalculator func(float64) basic.LunarEclipseResult
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// LunarEclipseShadowModel 标识月食用的是哪套影半径模型。
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// LunarEclipseShadowModel identifies which shadow-radius model produced a result.
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type LunarEclipseShadowModel = basic.LunarEclipseShadowModel
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const (
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// LunarEclipseShadowModelDanjon 是 Danjon 影半径模型。
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LunarEclipseShadowModelDanjon = basic.LunarEclipseShadowModelDanjon
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// LunarEclipseShadowModelChauvenet 是 Chauvenet 影半径模型。
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LunarEclipseShadowModelChauvenet = basic.LunarEclipseShadowModelChauvenet
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)
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// LunarEclipseType 月食类型 / lunar eclipse type.
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type LunarEclipseType string
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const (
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// LunarEclipseNone 无月食, no lunar eclipse.
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LunarEclipseNone LunarEclipseType = "none"
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// LunarEclipsePenumbral 半影月食, penumbral lunar eclipse.
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LunarEclipsePenumbral LunarEclipseType = "penumbral"
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// LunarEclipsePartial 月偏食, partial lunar eclipse.
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LunarEclipsePartial LunarEclipseType = "partial"
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// LunarEclipseTotal 月全食, total lunar eclipse.
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LunarEclipseTotal LunarEclipseType = "total"
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)
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// LunarEclipseContactPoint 表示月食接触点在月面上的方位。
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// LunarEclipseContactPoint describes a lunar eclipse contact point on the Moon limb.
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type LunarEclipseContactPoint struct {
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// Label 是接触标签，如 P1/U1/U2/U3/U4/P4。
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// Label is the contact label, such as P1/U1/U2/U3/U4/P4.
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Label string
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// Time 是该接触时刻，保持用户输入时区。
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// Time is the contact time, preserving the input timezone.
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Time time.Time
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// ContactPositionAngle 是月面接触点位置角，从天球北点起向东量，单位度。
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// ContactPositionAngle is the Moon-limb contact position angle from celestial north toward east, in degrees.
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ContactPositionAngle float64
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// ContactClockwiseAngle 是图面上从北点顺时针量到接触点的角度，单位度。
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// ContactClockwiseAngle is the chart clockwise angle from north to the contact point, in degrees.
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ContactClockwiseAngle float64
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// MoonCenterPositionAngle 是月心相对地影中心的位置角，从北点起向东量，单位度。
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// MoonCenterPositionAngle is the Moon-center position angle from the shadow center, in degrees.
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MoonCenterPositionAngle float64
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// ShadowCenterPositionAngle 是地影中心相对月心的位置角，从北点起向东量，单位度。
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// ShadowCenterPositionAngle is the shadow-center position angle from the Moon center, in degrees.
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ShadowCenterPositionAngle float64
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}
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// LunarEclipseInfo 月食信息, lunar eclipse information.
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//
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// 所有时刻字段都保持用户输入的时区。
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// 不存在的阶段使用零值 time.Time。
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type LunarEclipseInfo struct {
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// Type 月食类型, eclipse type.
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Type LunarEclipseType
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// HasSaros 存在沙罗序列信息（可能是锚点外推结果）, has Saros series metadata (possibly extrapolated).
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HasSaros bool
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// Saros 是沙罗序列信息，包括系列号、系列内序号和总成员数。
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// Saros is Saros series metadata with the series number, member index, and total member count.
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Saros SarosInfo
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// PenumbralMagnitude 半影食分, penumbral magnitude.
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PenumbralMagnitude float64
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// UmbralMagnitude 本影食分；纯半影月食时可为负值, umbral magnitude; can be negative for purely penumbral eclipses.
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UmbralMagnitude float64
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// PenumbralStart 半影始, penumbral eclipse begins.
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PenumbralStart time.Time
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// PartialStart 初亏, partial eclipse begins.
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PartialStart time.Time
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// TotalStart 食既, total eclipse begins.
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TotalStart time.Time
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// Maximum 食甚, greatest eclipse.
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Maximum time.Time
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// TotalEnd 生光, total eclipse ends.
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TotalEnd time.Time
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// PartialEnd 复圆, partial eclipse ends.
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PartialEnd time.Time
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// PenumbralEnd 半影终, penumbral eclipse ends.
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PenumbralEnd time.Time
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// GreatestJDE 是食甚的力学时儒略日；与 DeltaTSeconds 配对即可复现上列民用时刻。
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// GreatestJDE is the TT Julian ephemeris day of greatest eclipse; with DeltaTSeconds it reproduces the civil times above.
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GreatestJDE float64
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// DeltaTSeconds 是本次计算实际使用的 TT−UT1，单位秒。
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// DeltaTSeconds is the TT−UT1 used by this computation, in seconds.
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DeltaTSeconds float64
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// ContactPoints 是各接触时刻在月面上的接触点方位。
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// ContactPoints are Moon-limb contact position angles at eclipse contacts.
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ContactPoints []LunarEclipseContactPoint
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// ShadowModel 是本次使用的影半径模型，决定下列影几何与食分的具体数值。
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// ShadowModel is the shadow-radius model used; it fixes the shadow geometry and magnitudes below.
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ShadowModel LunarEclipseShadowModel
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// Gamma 是食甚时月心到地影轴的最小距离，单位地球赤道半径。
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// Gamma is the minimum distance from the Moon's centre to the shadow axis at greatest eclipse, in Earth equatorial radii.
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Gamma float64
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// AxisDegrees 是同一个角距的角度制数值，即 NASA 月食图上的 Axis；Gamma 除以月球处的地球视差即得。
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// AxisDegrees is the same distance in degrees, the Axis column of NASA lunar-eclipse charts; it equals Gamma divided by the Earth's parallax at the Moon.
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AxisDegrees float64
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// PenumbralRadiusDegrees 与 UmbralRadiusDegrees 是食甚时的半影、本影半径，单位度。
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// PenumbralRadiusDegrees and UmbralRadiusDegrees are the shadow radii at greatest eclipse, in degrees.
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PenumbralRadiusDegrees float64
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UmbralRadiusDegrees float64
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// MoonDistanceEarthRadii 是食甚时的地心月距。
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// MoonDistanceEarthRadii is the geocentric Moon distance at greatest eclipse.
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MoonDistanceEarthRadii float64
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// HasPenumbral 有半影阶段, has penumbral phase.
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HasPenumbral bool
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// HasPartial 有偏食阶段, has partial phase.
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HasPartial bool
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// HasTotal 有全食阶段, has total phase.
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HasTotal bool
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}
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// LunarEclipseOnDate 当地自然日月食查询 / local-date lunar eclipse query.
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// Determine whether a lunar eclipse occurs on the local date.
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// The default path uses Danjon and falls back to Chauvenet for ultra-shallow penumbral edge cases.
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//
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// 只要该自然日内有任意一个接触时刻，或整场月食与该自然日有时间重叠，就返回 true。
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func LunarEclipseOnDate(date time.Time) (LunarEclipseInfo, bool) {
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return lunarEclipseOnDateWithFallback(date, basic.LunarEclipseDanjon, true)
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}
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// LunarEclipseOnDateDanjon 当地自然日月食查询（Danjon） / local-date lunar eclipse query with Danjon model.
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// Determine whether a lunar eclipse occurs on the local date with the Danjon model.
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func LunarEclipseOnDateDanjon(date time.Time) (LunarEclipseInfo, bool) {
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return lunarEclipseOnDateWithFallback(date, basic.LunarEclipseDanjon, false)
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}
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// LunarEclipseOnDateChauvenet 当地自然日月食查询（Chauvenet） / local-date lunar eclipse query with Chauvenet model.
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// Determine whether a lunar eclipse occurs on the local date with the Chauvenet model.
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func LunarEclipseOnDateChauvenet(date time.Time) (LunarEclipseInfo, bool) {
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return lunarEclipseOnDateWithFallback(date, basic.LunarEclipseChauvenet, false)
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}
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func lunarEclipseOnDateWithFallback(date time.Time, calculator lunarEclipseCalculator, allowDefaultFallback bool) (LunarEclipseInfo, bool) {
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location := date.Location()
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dayStart, dayMid, dayEnd := lunarEclipseLocalDayBounds(date)
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phaseDiff := moonSunLoDiff(dayMid)
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if phaseDiff < lunarEclipseDayPhaseMin || phaseDiff > lunarEclipseDayPhaseMax {
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return LunarEclipseInfo{}, false
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}
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candidateTT := basic.CalcMoonSHByJDE(timeToTTJDE(dayMid), 1)
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if !isPotentialLunarEclipse(candidateTT) {
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return LunarEclipseInfo{}, false
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}
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result := calculator(candidateTT)
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if result.Type == basic.LunarEclipseNone && allowDefaultFallback {
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if fallback, ok := lunarEclipseDefaultFallback(candidateTT); ok {
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result = fallback
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}
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}
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if result.Type == basic.LunarEclipseNone {
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return LunarEclipseInfo{}, false
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}
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info := lunarEclipseInfoFromBasic(result, location)
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if !lunarEclipseOverlapsDate(info, dayStart, dayEnd) {
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return LunarEclipseInfo{}, false
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}
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return info, true
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}
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// LastLunarEclipse 上次月食 / previous lunar eclipse.
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// Previous lunar eclipse.
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// The default path uses Danjon and falls back to Chauvenet for ultra-shallow penumbral edge cases.
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func LastLunarEclipse(date time.Time) LunarEclipseInfo {
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info, _ := searchLunarEclipse(date, -1, true, basic.LunarEclipseDanjon, true)
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return info
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}
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// LastLunarEclipseDanjon 上次月食（Danjon） / previous lunar eclipse with Danjon model.
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// Previous lunar eclipse with the Danjon model.
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func LastLunarEclipseDanjon(date time.Time) LunarEclipseInfo {
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info, _ := searchLunarEclipse(date, -1, true, basic.LunarEclipseDanjon, false)
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return info
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}
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// LastLunarEclipseChauvenet 上次月食（Chauvenet） / previous lunar eclipse with Chauvenet model.
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// Previous lunar eclipse with the Chauvenet model.
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func LastLunarEclipseChauvenet(date time.Time) LunarEclipseInfo {
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info, _ := searchLunarEclipse(date, -1, true, basic.LunarEclipseChauvenet, false)
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return info
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}
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// NextLunarEclipse 下次月食 / next lunar eclipse.
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// Next lunar eclipse.
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// The default path uses Danjon and falls back to Chauvenet for ultra-shallow penumbral edge cases.
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func NextLunarEclipse(date time.Time) LunarEclipseInfo {
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info, _ := searchLunarEclipse(date, 1, false, basic.LunarEclipseDanjon, true)
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return info
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}
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// NextLunarEclipseDanjon 下次月食（Danjon） / next lunar eclipse with Danjon model.
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// Next lunar eclipse with the Danjon model.
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func NextLunarEclipseDanjon(date time.Time) LunarEclipseInfo {
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info, _ := searchLunarEclipse(date, 1, false, basic.LunarEclipseDanjon, false)
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return info
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}
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// NextLunarEclipseChauvenet 下次月食（Chauvenet） / next lunar eclipse with Chauvenet model.
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// Next lunar eclipse with the Chauvenet model.
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func NextLunarEclipseChauvenet(date time.Time) LunarEclipseInfo {
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info, _ := searchLunarEclipse(date, 1, false, basic.LunarEclipseChauvenet, false)
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return info
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}
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// ClosestLunarEclipse 最近一次月食 / closest lunar eclipse.
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// Closest lunar eclipse.
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// The default path uses Danjon and falls back to Chauvenet for ultra-shallow penumbral edge cases.
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func ClosestLunarEclipse(date time.Time) LunarEclipseInfo {
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last, hasLast := searchLunarEclipse(date, -1, true, basic.LunarEclipseDanjon, true)
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next, hasNext := searchLunarEclipse(date, 1, false, basic.LunarEclipseDanjon, true)
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return closestLunarEclipse(date, last, hasLast, next, hasNext)
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}
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// ClosestLunarEclipseDanjon 最近一次月食（Danjon） / closest lunar eclipse with Danjon model.
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// Closest lunar eclipse with the Danjon model.
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func ClosestLunarEclipseDanjon(date time.Time) LunarEclipseInfo {
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last, hasLast := searchLunarEclipse(date, -1, true, basic.LunarEclipseDanjon, false)
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next, hasNext := searchLunarEclipse(date, 1, false, basic.LunarEclipseDanjon, false)
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return closestLunarEclipse(date, last, hasLast, next, hasNext)
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}
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// ClosestLunarEclipseChauvenet 最近一次月食（Chauvenet） / closest lunar eclipse with Chauvenet model.
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// Closest lunar eclipse with the Chauvenet model.
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func ClosestLunarEclipseChauvenet(date time.Time) LunarEclipseInfo {
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last, hasLast := searchLunarEclipse(date, -1, true, basic.LunarEclipseChauvenet, false)
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next, hasNext := searchLunarEclipse(date, 1, false, basic.LunarEclipseChauvenet, false)
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return closestLunarEclipse(date, last, hasLast, next, hasNext)
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}
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func closestLunarEclipse(
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date time.Time,
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last LunarEclipseInfo,
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hasLast bool,
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next LunarEclipseInfo,
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hasNext bool,
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) LunarEclipseInfo {
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switch {
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case hasLast && !hasNext:
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return last
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case !hasLast && hasNext:
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return next
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case !hasLast && !hasNext:
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return LunarEclipseInfo{}
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}
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lastDistance := math.Abs(date.Sub(last.Maximum).Seconds())
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nextDistance := math.Abs(next.Maximum.Sub(date).Seconds())
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if lastDistance <= nextDistance {
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return last
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}
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return next
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}
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func searchLunarEclipse(
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date time.Time,
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direction int,
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includeCurrent bool,
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calculator lunarEclipseCalculator,
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allowDefaultFallback bool,
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) (LunarEclipseInfo, bool) {
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targetTT := timeToTTJDE(date)
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candidateTT := basic.CalcMoonSHByJDE(targetTT, 1)
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for i := 0; i < lunarEclipseSearchLimit; i++ {
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if isPotentialLunarEclipse(candidateTT) {
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result := calculator(candidateTT)
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if result.Type == basic.LunarEclipseNone && allowDefaultFallback {
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if fallback, ok := lunarEclipseDefaultFallback(candidateTT); ok {
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result = fallback
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}
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}
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if result.Type != basic.LunarEclipseNone && lunarEclipseMatchesDirection(result.Maximum, targetTT, direction, includeCurrent) {
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return lunarEclipseInfoFromBasic(result, date.Location()), true
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}
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}
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candidateTT = nextEclipseSearchCandidateTT(candidateTT, 1, direction, lunarEclipseSynodicMonthDays)
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}
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return LunarEclipseInfo{}, false
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}
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func lunarEclipseDefaultFallback(candidateTT float64) (basic.LunarEclipseResult, bool) {
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result := basic.LunarEclipseChauvenet(candidateTT)
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if result.Type != basic.LunarEclipsePenumbral {
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return basic.LunarEclipseResult{}, false
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}
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if result.HasPartial || result.HasTotal {
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return basic.LunarEclipseResult{}, false
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}
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if result.PenumbralMagnitude <= 0 || result.PenumbralMagnitude > lunarEclipseDefaultFallbackMaxPenumbralMagnitude {
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return basic.LunarEclipseResult{}, false
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}
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return result, true
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}
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func lunarEclipseMatchesDirection(maximumTT, targetTT float64, direction int, includeCurrent bool) bool {
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delta := maximumTT - targetTT
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if math.Abs(delta) <= lunarEclipseSearchEpsilonDay {
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return direction < 0 && includeCurrent
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}
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if direction > 0 {
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return delta > 0
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}
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return delta < 0
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}
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func isPotentialLunarEclipse(fullMoonTT float64) bool {
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moonLatitude := math.Abs(basic.HMoonTrueBo(fullMoonTT))
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if moonLatitude > lunarEclipseLatitudeLimitDeg {
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return false
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}
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phaseDiff := math.Abs(normalizeDegree180(basic.HMoonApparentLo(fullMoonTT) - basic.HSunApparentLo(fullMoonTT) - 180))
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return phaseDiff <= lunarEclipseLongitudeLimitDeg
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}
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func lunarEclipseInfoFromBasic(result basic.LunarEclipseResult, location *time.Location) LunarEclipseInfo {
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saros, hasSaros := lunarSarosInfo(result.Maximum)
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geometry := basic.LunarEclipseShadowGeometryAtModel(result.Maximum, result.ShadowModel)
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return LunarEclipseInfo{
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ShadowModel: LunarEclipseShadowModel(result.ShadowModel),
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Gamma: geometry.Gamma,
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AxisDegrees: geometry.AxisDegrees,
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PenumbralRadiusDegrees: geometry.PenumbralRadiusDegrees,
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UmbralRadiusDegrees: geometry.UmbralRadiusDegrees,
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MoonDistanceEarthRadii: geometry.MoonDistanceEarthRadii,
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HasSaros: hasSaros,
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Saros: saros,
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Type: mapBasicLunarEclipseType(result.Type),
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PenumbralMagnitude: result.PenumbralMagnitude,
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UmbralMagnitude: result.Magnitude,
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PenumbralStart: ttJDEToTime(result.PenumbralStart, location),
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PartialStart: ttJDEToTime(result.PartialStart, location),
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TotalStart: ttJDEToTime(result.TotalStart, location),
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Maximum: ttJDEToTime(result.Maximum, location),
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TotalEnd: ttJDEToTime(result.TotalEnd, location),
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PartialEnd: ttJDEToTime(result.PartialEnd, location),
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PenumbralEnd: ttJDEToTime(result.PenumbralEnd, location),
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GreatestJDE: result.Maximum,
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DeltaTSeconds: basic.DeltaT(result.Maximum, true),
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ContactPoints: lunarEclipseContactPointsFromBasic(result, location),
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HasPenumbral: result.HasPenumbral,
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HasPartial: result.HasPartial,
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HasTotal: result.HasTotal,
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}
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}
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func lunarEclipseContactPointsFromBasic(
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result basic.LunarEclipseResult,
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location *time.Location,
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||
) []LunarEclipseContactPoint {
|
||
if !result.HasPenumbral {
|
||
return nil
|
||
}
|
||
|
||
contacts := []LunarEclipseContactPoint{
|
||
lunarEclipseContactPoint("P1", result.PenumbralStart, location, false),
|
||
}
|
||
if result.HasPartial {
|
||
contacts = append(contacts, lunarEclipseContactPoint("U1", result.PartialStart, location, false))
|
||
}
|
||
if result.HasTotal {
|
||
contacts = append(contacts, lunarEclipseContactPoint("U2", result.TotalStart, location, true))
|
||
}
|
||
if result.HasTotal {
|
||
contacts = append(contacts, lunarEclipseContactPoint("U3", result.TotalEnd, location, true))
|
||
}
|
||
if result.HasPartial {
|
||
contacts = append(contacts, lunarEclipseContactPoint("U4", result.PartialEnd, location, false))
|
||
}
|
||
contacts = append(contacts, lunarEclipseContactPoint("P4", result.PenumbralEnd, location, false))
|
||
return contacts
|
||
}
|
||
|
||
func lunarEclipseContactPoint(
|
||
label string,
|
||
ttJDE float64,
|
||
location *time.Location,
|
||
internalContact bool,
|
||
) LunarEclipseContactPoint {
|
||
moonCenterPA := lunarEclipseMoonCenterPositionAngle(ttJDE)
|
||
shadowCenterPA := normalizeDegree360(moonCenterPA + 180)
|
||
contactPA := shadowCenterPA
|
||
if internalContact {
|
||
contactPA = moonCenterPA
|
||
}
|
||
return LunarEclipseContactPoint{
|
||
Label: label,
|
||
Time: ttJDEToTime(ttJDE, location),
|
||
ContactPositionAngle: contactPA,
|
||
ContactClockwiseAngle: normalizeDegree360(360 - contactPA),
|
||
MoonCenterPositionAngle: moonCenterPA,
|
||
ShadowCenterPositionAngle: shadowCenterPA,
|
||
}
|
||
}
|
||
|
||
func lunarEclipseMoonCenterPositionAngle(ttJDE float64) float64 {
|
||
shadowRA, shadowDec := lunarEclipseShadowCenterRaDec(ttJDE)
|
||
moonRA, moonDec := basic.HMoonTrueRaDec(ttJDE)
|
||
return positionAngle(shadowRA, shadowDec, moonRA, moonDec)
|
||
}
|
||
|
||
func lunarEclipseShadowCenterRaDec(ttJDE float64) (float64, float64) {
|
||
sunRA, sunDec := basic.HSunApparentRaDec(ttJDE)
|
||
return normalizeDegree360(sunRA + 180), -sunDec
|
||
}
|
||
|
||
func positionAngle(fromRA, fromDec, toRA, toDec float64) float64 {
|
||
dRA := (toRA - fromRA) * math.Pi / 180
|
||
fromDecRad := fromDec * math.Pi / 180
|
||
toDecRad := toDec * math.Pi / 180
|
||
angle := math.Atan2(
|
||
math.Sin(dRA),
|
||
math.Cos(fromDecRad)*math.Tan(toDecRad)-math.Sin(fromDecRad)*math.Cos(dRA),
|
||
) * 180 / math.Pi
|
||
return normalizeDegree360(angle)
|
||
}
|
||
|
||
func mapBasicLunarEclipseType(eclipseType basic.LunarEclipseType) LunarEclipseType {
|
||
switch eclipseType {
|
||
case basic.LunarEclipsePenumbral:
|
||
return LunarEclipsePenumbral
|
||
case basic.LunarEclipsePartial:
|
||
return LunarEclipsePartial
|
||
case basic.LunarEclipseTotal:
|
||
return LunarEclipseTotal
|
||
default:
|
||
return LunarEclipseNone
|
||
}
|
||
}
|
||
|
||
func lunarEclipseOverlapsDate(info LunarEclipseInfo, dayStart, dayEnd time.Time) bool {
|
||
eventStart, eventEnd, ok := lunarEclipseRange(info)
|
||
if !ok {
|
||
return false
|
||
}
|
||
return !eventEnd.Before(dayStart) && eventStart.Before(dayEnd)
|
||
}
|
||
|
||
func lunarEclipseRange(info LunarEclipseInfo) (time.Time, time.Time, bool) {
|
||
if !info.HasPenumbral {
|
||
return time.Time{}, time.Time{}, false
|
||
}
|
||
return info.PenumbralStart, info.PenumbralEnd, true
|
||
}
|
||
|
||
func ttJDEToTime(ttJDE float64, location *time.Location) time.Time {
|
||
// basic 用 NaN 表示"该阶段不发生"（0 是 −4713-11-24 的真实时刻），
|
||
// 这里必须一并当空值处理，否则 NaN 会被换算成 −296 年那种假时刻。
|
||
if ttJDE == 0 || math.IsNaN(ttJDE) || math.IsInf(ttJDE, 0) {
|
||
return time.Time{}
|
||
}
|
||
utcJD := basic.TT2UTC(ttJDE)
|
||
return basic.JD2DateByZone(utcJD, location, false)
|
||
}
|
||
|
||
func timeToTTJDE(date time.Time) float64 {
|
||
utcJD := basic.Date2JD(date.UTC())
|
||
return basic.UTC2TT(utcJD)
|
||
}
|
||
|
||
func normalizeDegree180(angle float64) float64 {
|
||
angle = math.Mod(angle, 360)
|
||
if angle > 180 {
|
||
angle -= 360
|
||
}
|
||
if angle <= -180 {
|
||
angle += 360
|
||
}
|
||
return angle
|
||
}
|
||
|
||
func normalizeDegree360(angle float64) float64 {
|
||
angle = math.Mod(angle, 360)
|
||
if angle < 0 {
|
||
angle += 360
|
||
}
|
||
return angle
|
||
}
|
||
|
||
func lunarEclipseLocalDayBounds(date time.Time) (time.Time, time.Time, time.Time) {
|
||
location := date.Location()
|
||
dayStart := time.Date(date.Year(), date.Month(), date.Day(), 0, 0, 0, 0, location)
|
||
dayMid := time.Date(date.Year(), date.Month(), date.Day(), 12, 0, 0, 0, location)
|
||
dayEnd := time.Date(date.Year(), date.Month(), date.Day()+1, 0, 0, 0, 0, location)
|
||
return dayStart, dayMid, dayEnd
|
||
}
|
||
|
||
func nextLunarEclipseLocalDayStart(dayStart time.Time) time.Time {
|
||
location := dayStart.Location()
|
||
return time.Date(dayStart.Year(), dayStart.Month(), dayStart.Day()+1, 0, 0, 0, 0, location)
|
||
}
|