astro/jupiter/phenomena.go

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package jupiter
import (
"time"
"b612.me/astro/basic"
)
// GalileanSatellitePhenomenon 木星伽利略卫星瞬时现象 / instantaneous Galilean-satellite phenomena.
//
// Transit 为凌日Occultation 为掩蔽Eclipse 为进入木星本影ShadowTransit 为卫星影子落在可见木星盘面上。
// ShadowOffset* 仅在 ShadowTransit 为 true 时有意义。
// Transit means a transit across Jupiter's disk, Occultation means hidden behind Jupiter, Eclipse means inside Jupiter's umbra, and ShadowTransit means the shadow falls on the visible Jovian disk.
// ShadowOffset* are meaningful only when ShadowTransit is true.
type GalileanSatellitePhenomenon struct {
Transit bool
Occultation bool
Eclipse bool
ShadowTransit bool
ShadowOffsetXArcsec float64
ShadowOffsetYArcsec float64
ShadowOffsetXJupiterR float64
ShadowOffsetYJupiterR float64
}
// GalileanPhenomenaInfo 四颗伽利略卫星瞬时现象 / instantaneous phenomena of the four Galilean satellites.
type GalileanPhenomenaInfo struct {
Io GalileanSatellitePhenomenon
Europa GalileanSatellitePhenomenon
Ganymede GalileanSatellitePhenomenon
Callisto GalileanSatellitePhenomenon
}
// SatellitePhenomena 木星四颗伽利略卫星瞬时现象 / instantaneous phenomena of Jupiter's four Galilean satellites.
//
// date 表示观测绝对时刻;内部使用该时刻对应的 TT/TDB 历元求值。
// date is the observing instant; internally the corresponding TT/TDB epoch is used.
func SatellitePhenomena(date time.Time) GalileanPhenomenaInfo {
jde := basic.Date2JDE(date.UTC())
phenomena := basic.JupiterGalileanSatellitePhenomena(jde)
return GalileanPhenomenaInfo{
Io: galileanPhenomenonFromBasic(phenomena[0]),
Europa: galileanPhenomenonFromBasic(phenomena[1]),
Ganymede: galileanPhenomenonFromBasic(phenomena[2]),
Callisto: galileanPhenomenonFromBasic(phenomena[3]),
}
}
func galileanPhenomenonFromBasic(phenomenon basic.JupiterGalileanPhenomenon) GalileanSatellitePhenomenon {
return GalileanSatellitePhenomenon{
Transit: phenomenon.Transit,
Occultation: phenomenon.Occultation,
Eclipse: phenomenon.Eclipse,
ShadowTransit: phenomenon.ShadowTransit,
ShadowOffsetXArcsec: phenomenon.ShadowOffsetXArcsec,
ShadowOffsetYArcsec: phenomenon.ShadowOffsetYArcsec,
ShadowOffsetXJupiterR: phenomenon.ShadowOffsetXJupiterRadii,
ShadowOffsetYJupiterR: phenomenon.ShadowOffsetYJupiterRadii,
}
}