Moon is catalogued in this registry as a moon, held in the frame of Earth, from Solar system (curated).
Registry id MOON ·
source layer solar ·
provenance RAW — read directly from a source catalogue, unaltered
Open Moon in the live scene → The scene composes a position for any date and is where a figure becomes a picture. It downloads the whole catalogue first: measured against the built product, an object outside the core resolves after about 16 s over a local network and about 147 s over a 4 Mbit link, having transferred roughly 70 MB. If you cannot wait that long, this page is the answer.
| Quantity | Value | Uncertainty | Source |
|---|---|---|---|
| Radius | 1737400 m (1737.4 km) | no published uncertainty in this registry | Solar system (curated) ✓ confirmed by 1 further source: JPL SSD phys_par |
| Mass | 7.342×10^22 kg | no published uncertainty in this registry | Solar system (curated) |
Each row carries its own uncertainty and its own source. Where a row says no uncertainty is published, that is what the catalogue says — it is not a claim that the value is exact.
These are the sourced elements. This page does not print a position: a position is a function of time, and a single one dated to the bake would be stale the moment it was read. The registry composes a position for any date, past or future, from these elements — open the scene below and set the clock.
| Quantity | Value | Uncertainty | Source |
|---|---|---|---|
| Semi-major axis | 3.833978×10^8 m (383397.8 km) | no published uncertainty in this registry | Solar system (curated) ✓ confirmed by 1 further source: JPL SSD sats/elem |
| Eccentricity | 0.0549 | no published uncertainty in this registry | Solar system (curated) ✓ confirmed by 1 further source: JPL SSD sats/elem |
| Inclination | 0.089797 rad (5.145°) | no published uncertainty in this registry | Solar system (curated) ✓ confirmed by 1 further source: JPL SSD sats/elem |
| Longitude of ascending node | 2.182439 rad (125.0445°) | no published uncertainty in this registry | Solar system (curated) |
| Argument of periapsis | 5.555531 rad (318.3085°) | no published uncertainty in this registry | Solar system (curated) |
| Mean anomaly at epoch | 2.355556 rad (134.9634°) | no published uncertainty in this registry | Solar system (curated) |
Elements are expressed in the frame of
EARTH at epoch
2000-01-01 12:00:00 UTC (JD 2451545). Gravitational parameter of the primary:
4.0240947×10^14 m³/s². Semi-major axis in astronomical units uses the
IAU 2012 definition (1 au = 1.495978707×10^11 m exactly).
| Kind | moon |
|---|---|
| Origin | natural |
a/e/mass/radius [JPL SSD]; mean elements + secular rates [Chapront-Touzé & Chapront 1983, A&A 124, 50; mean arguments as tabulated in Meeus, Astronomical Algorithms 2nd ed. ch. 47], reduced to the ecliptic and equinox of J2000 (general precession, Meeus ch. 21). Node and apse precession MODELLED (linear); periodic terms (evection, variation) are NOT — the residual against ELP-2000/82 is worst 2.38° over 1940–2060. Synchronous (tidally locked) rotation from the IAU/NAIF Mean Earth/Polar Axis model: W = 38.3213° + 13.17635815°/day [NAIF pck00011.tpc; IAU WGCCRE, Archinal et al. 2011]. The sub-Earth longitude therefore stays near 0° at every epoch, and the ±~7° that remains is the real optical libration in longitude. Declined, with measured magnitudes: the 13 nutation terms in W (≤0.053° in prime-meridian longitude, because the matching pole terms cancel them), the 18.6-year Cassini precession of the pole (≤3.1°, 0.76° at 2026-08-05), and the ME↔principal-axis difference (~0.03°). Orbital mean motion set from the measured sidereal period 27.321661 d [JPL SSD] so the rotation stays locked to it; μ is then a two-body reconciliation constant, 0.27% below G(M⊕+M☾). Eclipse mode: position read from the lunar series instead (Meeus ch. 47, truncated ELP-2000/82; ±10″), MODELLED.
Reproduced as the source wrote it. Author-year citations link to their DOI where one is registered.
These are absences in the catalogues aggregated here, not measurements of zero, and not statements that the quantity is unknown to science:
| Database | Solar system (curated) |
|---|---|
| Authority | Standish 1992 mean elements; JPL SSD satellites; IAU spin data |
| Licence | Public ephemerides; textures CC BY 4.0 (Solar System Scope) |
| How it entered | Curated data-as-code (src/ingest/catalogs/solar.ts) |
| Coverage | Sol + 8 planets + 7 dwarfs/asteroids + 22 major moons, rings, spin axes |
This database remains the property of its owners and is reused under its own licence. If you quote a value from this page, name that database alongside SolarSystemRegistry.org.