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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 · Facts, line drawings and positions

heliocentricModelfunction

The theory that heliocentric(planet, ms) answers with, given the tables loaded now: VSOP87B for Mercury to Neptune, a fitted Chebyshev table where one covers the moment, else osculating elements (a dwarf planet) or JPL's approximate elements (Pluto outside its table). worstArcseconds is the fitted table's measured worst on samples held back from the fit, not a bound for every date; null where no such measurement exists. Ask again after importing a table or for another moment.

Import it

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

Definition

function heliocentricModel(planet: HostId, ms: number): { theory: "vsop87b" | "chebyshev" | "osculating-elements" | "approximate-elements"; worstArcseconds: number | null; }

Parameters

NameTypeDescription
planetHostId

A planet or dwarf planet.

msnumber

The moment in milliseconds since 1970 (UTC).

Returns

{ theory: "vsop87b" | "chebyshev" | "osculating-elements" | "approximate-elements"; worstArcseconds: number | null; }

The theory's name and its measured worst error in arc-seconds, or null.

Examples

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

console.log(heliocentricModel("pluto", Date.UTC(2026, 0, 1)));
{ theory: 'chebyshev', worstArcseconds: 0.14637 }

What it prints (run when this page was built)

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