SATELLITES AND SMALL BODIES
Snapshot retrieved 2026-10-09. The included snapshot covers all 455 rows for the
8 planets in JPL's available mean-orbit table, not a promise of all discoveries.
Mercury and Venus have no known natural satellites. Pluto is outside the existing
8-planet workspace. JPL's discovery list and its mean-orbit table have different
update schedules; do not interpret this snapshot's counts as an IAU census.
Earth 1; Mars 2; Jupiter 115; Saturn 291; Uranus 30; Neptune 16.

JPL Solar System Dynamics mean satellite elements:
https://ssd.jpl.nasa.gov/sats/elem/
JPL SBDB query API:
https://ssd-api.jpl.nasa.gov/doc/sbdb_query.html
1,200 main-belt asteroids selected by H<12 and increasing H; 12 bound periodic
comets with e<1. The full SBDB contains many more objects. Source names/elements
are retained in population.json; no procedural body catalog is substituted.
Generator: scripts/build-population-data.py (Python standard library).

Other satellite and minor-body positions use fixed mean elliptic elements,
J2000 reference-plane conversion and Kepler motion. Laplace-plane poles and
planet-equatorial poles preserve inclinations and retrograde directions. The
approximation omits changing elements, perturbations, resonances and precession;
do not use it for occultations, conjunction times, navigation or precision sky
coordinates, especially far from the source epoch. Epoch TDB is approximated by
TT; their millisecond difference is immaterial for this illustrative layer.
The original Astronomy Engine planetary/Moon models are unchanged. Earth's
Moon and the four Galilean moons use the existing engine's state vectors.
Satellite spacing is logarithmically enlarged, independent of parent display
radius. Markers are enlarged points, not physical sizes or brightness models.
Only the selected system is shown in closeup; the overview contains all loaded
planetary satellites without text labels. No new physical clock is introduced.

REAL NEBULA PHOTOGRAPHS
Images redistributed unchanged from the NASA Image and Video Library:
Orion: PIA01322, NASA/JPL-Caltech/STScI (Hubble + Spitzer composite).
https://images.nasa.gov/details/PIA01322
Ring Nebula: GSFC_20171208_Archive_e001464, NASA, ESA, C.R. Robert O'Dell
(Vanderbilt University), G.J. Ferland (University of Kentucky), W.J. Henney and
M. Peimbert (National Autonomous University of Mexico); LBT data: David Thompson
(University of Arizona). Visible-light Hubble and infrared LBT composite.
https://images.nasa.gov/details/GSFC_20171208_Archive_e001464
Carina / Mystic Mountain: GSFC_20171208_Archive_e002076, NASA, ESA, M. Livio and
the Hubble 20th Anniversary Team (STScI). Hubble observation, released 2010.
https://images.nasa.gov/details/GSFC_20171208_Archive_e002076
The complete original metadata is retained in nebulae/catalog.json.
Image-use guidance: https://www.nasa.gov/nasa-brand-center/images-and-media/
No endorsement is implied. Respect original agency/contributor credits.

These are processed/multi-band telescope exposures, not naked-eye views or
current weather. The optional background enlarges the photos, softens their
edges and places them near the objects' approximate celestial directions for
illustration. It does not preserve real angular size, image plate solution or
orientation. The viewer displays the unchanged photograph. Nebulae are remote
interstellar objects, not bodies inside the solar system. No generated artwork
is presented as telescope imagery.