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Wakusei Planets惑星

The Sun, the planets and their moons as a clean line drawing, a shaded realistic drawing or a painted surface map, with real sizes, tilt and rotation, and the moons where they are at any date and time.

Wakusei is the Japanese word 惑星 for a planet. About the name

Contents

Reference

Julian dates (and the julian package's functions), calendars, time scales, sidereal time and Mars time

import { … } from "@johnmorrisdotca/wakusei-planets/time";

Exports

NameKindWhat it is
B1950_JDconstantThe Julian date of the Besselian epoch B1950.0, 1950 January 0.923 (Meeus).
CalendartypeWhich calendar: gregorian and julian are used for every year (the proleptic calendars), and auto follows history: the Julian calendar to 1582-10-04 and the Gregorian from 1582-10-15.
CivilTimetypeA date and time of day.
convertTimeScalefunctionA moment on one time scale as the same moment on another, in milliseconds since 1970 read on the target scale's own clock.
coordinatedMarsTimefunctionCoordinated Mars Time: the mean solar time on Mars's prime meridian, in hours from 0 up to 24 (a Martian hour is 1/24 of a sol).
dayOfWeekfunctionThe day of the week of a moment in UTC: 0 Sunday to 6 Saturday.
dayOfYearfunctionThe day of the year of a moment in UTC: 1 on 1 January.
daysInMonthfunctionThe number of days in a month; October 1582 has 21 in the auto calendar, the ten days of the switch being left out.
deltaTfunctionDelta T, terrestrial time minus universal time (UT1), in seconds.
equationOfTheEquinoxesfunctionThe equation of the equinoxes in degrees: the nutation in longitude times the cosine of the obliquity, what apparent sidereal time has over mean (about 1 second of time at most).
fromCalendarfunctionA date and time of day in UTC as a moment, in milliseconds since 1970.
fromJulianDatefunctionThe time, in milliseconds since 1970, of a Julian date.
fromJulianDayAndMillisecondsfunctionA time from a Julian day and the milliseconds into it, with no digit lost: fromJulianDayAndMilliseconds(toJulianDay(t), toMillisecondsInJulianDay(t)) is t.
greenwichApparentSiderealTimefunctionThe Greenwich apparent sidereal time in degrees, 0 to 360: the mean time with the equation of the equinoxes added, which is what the hour angle of a body is measured against.
greenwichMeanSiderealTimefunctionThe Greenwich mean sidereal time in degrees, 0 to 360 (divide by 15 for hours).
isLeapYearfunctionWhether a year is a leap year.
J2000_JDconstantThe Julian date of J2000.0, 2000-01-01 12:00 TT: the epoch of the planets' theories.
J2000_MSconstantJ2000.0, 2000-01-01 12:00, as milliseconds since 1970 counted on a clock that reads TT: a terrestrial time is this far from it.
julianfunctionA time as a string of its Julian date with six decimals, as the julian package gives it (a tenth of a second).
julianCenturiesfunctionJulian centuries (36,525 days) from J2000.0: the time argument of most theories.
julianMillenniafunctionJulian millennia (365,250 days) from J2000.0, in terrestrial time unless scale says UTC: the time argument of the VSOP87 series.
localSiderealTimefunctionThe local sidereal time in degrees, 0 to 360, at a longitude east of Greenwich (west negative): the right ascension on the meridian.
marsLocalMeanSolarTimefunctionThe local mean solar time on Mars at a longitude east of its prime meridian, in hours from 0 up to 24.
marsSolDatefunctionThe Mars Sol Date: the count of Martian days, as the Julian date counts Earth's.
modifiedJulianDatefunctionThe modified Julian date: the Julian date less 2,400,000.5, so a day starts at midnight and the numbers are shorter.
taiMinusUtcfunctionTAI minus UTC in seconds: the leap seconds from 1972 (10 then, 37 since 2017), and before 1972 delta T less 32.184, which is how far the atomic scale would have been from the Earth's turn.
tdbMinusTtfunctionTDB minus TT in seconds: a term that follows the Earth round the Sun and is never more than 1.7 milliseconds (Meeus's two terms, 0.001657 sin g and 0.000014 sin 2g, good to about 30 microseconds).
TimeScaletypeA time scale: utc (the clock), ut1 (the Earth's turn, within 0.9 s of UTC), tai (atomic time), gps (TAI less 19 s), tt (terrestrial time, TAI plus 32.184 s) and tdb (barycentric dynamical time, TT plus a few milliseconds that follow the year).
toCalendarfunctionA moment as a date and time of day in UTC, in the Gregorian or the Julian calendar.
toDatefunctionThe Date of a Julian date (a number, or the string julian gives), rounded to the millisecond.
toJulianDatefunctionA time as a Julian date: the days since noon on 1 January 4713 BC (Julian calendar), as a number.
toJulianDayfunctionThe whole Julian day of a time.
toMillisecondsInJulianDayfunctionThe milliseconds since noon, the start of the Julian day, that a time is into it.
toTerrestrialTimefunctionA moment in UTC as the same moment in terrestrial time, on the same scale of milliseconds since 1970.
ttMinusUtcfunctionTerrestrial time minus the clock's time, in seconds, at a moment given in UTC: 69.184 from the last leap second in 2017 on (until another is added), exact from 1972, and delta T before.
UNIX_EPOCH_JULIAN_DATEconstantThe Julian date of the Unix epoch, 1970-01-01T00:00:00Z (UTC).
WhentypeA moment: a Date or a number of milliseconds since 1970 (UTC, as JavaScript counts).

View sourceEdit on GitHubMade from the source of @johnmorrisdotca/wakusei-planets 0.24.0.