Everything we draw, and where it came from.

J2000 positions, brightness and colour index, trimmed to magnitude 6.5 by a committed tool. Credit astronexus (astronexus.com). The CC BY-SA 4.0 licence covers this star file only; the code stays MIT. The Yale Bright Star Catalogue stays a local-only option and is never shipped.

CC BY 4.0, credit ESO/S. Brunier. Split into two halves at the galactic centre. Good to a few degrees, and soft beside the stars: a sharper one is on the wish list.

Earth's spin and tilt from the IAU 2006 and 2000B models.

Open-source library

Compared with JPL Horizons across 1969 to 2030.

Open-source library

Checked against JPL Horizons (DE441) at six dates, 1969 to 2030. Rotation from the IAU 2015 report.

Published theory

A simple model, checked against JPL Horizons. Good for showing, not for navigating.

JPL published values

Whole 133-year orbit, out to 51 AU. Within 1% of its distance from the Sun at eight dates.

Within 11,000 km at the 2026 Geminid peak, 2% off near the Sun six years earlier.

Paths rebuilt between NASA's published anchor points, with 30 events timed to a tenth of a second.

Measured orbits from the CAMS camera network. Terms not yet confirmed, so CAMS is not the default source and stays on this machine until Dr. Jenniskens replies.

Same terms question as the Perseids.

CC BY 4.0. About 30,000 Perseids a year. The default source for the Perseids and the Geminids, public with credit. 25,588 Perseid orbits drawn (July and August 2025) and 51,115 Geminid orbits (December 2024 and 2025).

Peak solar longitude, radiant and speed from the IAU (J2000). Activity dates and peak rate from the American Meteor Society.

Published reference values

Every moment is converted once, in one place, so the Moon, the planets and the spacecraft all agree on what "now" means.

orb.js time scales

Positions are held in one fixed sky frame (J2000) and converted for drawing. "Up" can be celestial north, or flat to the planets' plane.

IAU standards

Planets from a full published theory. Comets, asteroids and every meteor from classical orbital elements, solved per frame.

Bretagnon & Francou 1988

The scene is re-centred on whatever you look at, so a body 51 AU out still sits still on screen. Measured: under a hundredth of a pixel of drift.

The peak is the moment the Sun reaches the published longitude. Pinned against NASA's Earth positions to within 0.005°.

A published quality cut: a wide enough viewing angle between cameras (15° or more) and a speed error of 10% or less. A switch between all and reliable.

The Perseid orbits pass closest to Earth 2.2 hours before the official peak. The radiant they imply is 0.04° from the IAU's, and the median speed of the members crossing near Earth is 58.75 km/s against the IAU's 58.8.

Where each meteor sits along its orbit today wasn't measured, so the dots are spread evenly and labelled illustrative. The bunch near the comet is a labelled model.

Shown in every info panel and story panel

Seven panels for Apollo 11 and three for the Perseids. Each opens when playback reaches its moment, wears one of the three badges, and lists its sources: the NASA mission report for Apollo 11, and the IAU, the American Meteor Society, JPL and the Global Meteor Network for the Perseids. Seven Apollo panels are marked observed. Of the Perseid panels, two are observed and one illustrative.

ESO/S. Brunier. eso0932a, eso.org/public/images/eso0932a. Changed: split in two and turned into the J2000 sky frame.

Solar System Scope (solarsystemscope.com/textures), based on NASA imagery and elevation data.

USGS Astrogeology Science Center; NASA/JPL Galileo and Voyager missions.

NASA Earth Observatory (Blue Marble: Next Generation, Reto Stöckli). July 2004 with topography and bathymetry, science.nasa.gov/earth/earth-observatory/blue-marble-next-generation. Changed: resampled to 4096×2048.

NASA's Scientific Visualization Studio. CGI Moon Kit, svs.gsfc.nasa.gov/4720, LROC WAC colour map with polar fill. Changed: converted to JPEG.

Global Meteor Network, globalmeteornetwork.org. Vida et al. 2020, MNRAS 491(2); Vida et al. 2021, MNRAS 506(4).

CAMS Meteoroid Orbit Database v3, P. Jenniskens, SETI Institute. Jenniskens et al. 2018, Planetary and Space Science 154.

Jenniskens et al. 2020, Planetary and Space Science 182; Jopek & Kaňuchová 2017, Planetary and Space Science 143.

HYG database v4.2 (Hipparcos, Yale Bright Star and Gliese catalogues), astronexus, astronexus.com/projects/hyg. Changed: stars of magnitude 6.5 or brighter kept, right ascension converted from hours to degrees. The licence covers this star file only; the code stays MIT.

Yale Bright Star Catalogue, 5th revised edition, Hoffleit & Warren 1991, via CDS Strasbourg. Fetched on request, never shipped.

NASA/JPL Horizons and Small-Body Database. orb.js by lizard-isana. VSOP87, Bretagnon & Francou 1988. IAU WGCCRE 2015 report, Archinal et al. 2018.

Some code ideas (camera gestures, atmosphere glow, picture loading, info-panel layout) and the Mercury, Venus, Mars and Io pictures came from planetary-explorer.anipatke.com. The story panel's look and behaviour (side panel, phone bottom sheet, marker dot, badge) follow its panel parts, rewritten for Astraeus.

NASA Apollo 11 Mission Report, MSC-00171 / SP-238.

American Meteor Society, Meteor Shower Calendar 2026/2027.

USGS Astrogeology, Voyager and Galileo SSI global mosaics. Ganymede matches the 1 km mosaic, turned half a revolution.

Ready

Solar System Scope, same terms as the planet maps above. Uranus and Neptune are byte-for-byte the published files.

Ready

Cassini global maps PIA17214, PIA18435, PIA18439, PIA18434, PIA18438, PIA19658, PIA18436. NASA/JPL-Caltech/Space Science Institute (and Lunar and Planetary Institute for the colour maps). JPL allows use for any purpose with credit.

Dione and Mimas need resizing

Voyager 2 map PIA18668, NASA/JPL-Caltech/Lunar & Planetary Institute. Voyager saw about half the surface.

Needs resizing

New Horizons global colour map PIA11707, NASA/JHUAPL/SwRI. Matches the published file. The southern third was in darkness during the flyby and is black.

Ready

USGS Astrogeology, Charon New Horizons LORRI MVIC global mosaic 300 m (2017). The file is the USGS 1024-pixel preview, so a sharper copy should come from the full mosaic.

Low resolution

The surface is real Dawn framing-camera imagery and lines up with the USGS/DLR global mosaic. The added colour and the yellow polar fill have no known source. Use the traced USGS mosaic instead.

Replace

Drawn in code as bands, with edges from NASA's planetary ring fact sheets (nssdc.gsfc.nasa.gov/planetary/factsheet) and colours matched by eye to NASA spacecraft photos. Saturn, Uranus and Neptune match the fact sheets. Jupiter's bands sit about a fifth too close to the planet.

Jupiter to correct