Attributions & sources.

People & AI assistance

Global data & tools

Credit does not imply endorsement. Referenced publications and linked media retain their respective rights; the app’s code license does not relicense third-party data or media.

Earth, Solar System & Galaxy

Additional mission data and credits: Voyager 2 samples · New Horizons samples · Webb samples. Each asset preserves NASA/JPL source queries, response checksums and interpolation checks. Import methods & mission references.

• NASA Voyager 2: planet encounters · November 5, 2018 heliopause crossing. Later trajectory: R. Jacobson’s 2022 tracking-data refit.
• NASA New Horizons: mission and milestones. Navigation solutions: New Horizons navigation / KinetX; Pluto-system reconstruction and Arrokoth mission-target solution identified in the retained Horizons header.
• NASA Webb: orbit around L2 · January 24, 2022 insertion burn. Ephemerides: NASA Goddard Flight Dynamics Facility, distributed by JPL Horizons.

Traveler image labels use locally served NASA illustrations, not live views or spacecraft attitude solutions. They appear when the selected traveler is followed or approached closely; the distance comparison also includes pictures. Image sizes are not physical scale.

• Voyager 1 & 2: NASA/JPL · PIA04495 · artist concept.
• New Horizons: NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute · PIA10075 · artist concept.
• Webb: NASA · spacecraft artist concept.
• NASA media-use guidelines. Educational use with attribution; no endorsement implied. Image provenance and download links.

The glowing heliosphere is a schematic round solar-wind bubble with a 120 AU reference radius, not a measured boundary or a forecast. Oort Cloud glows emphasize uncertain distance guides, not detected surfaces or comet densities. Tap reference lines or keyboard-accessible labels for explanations.

Galactic sky: real catalog directions, stylized star sizes, colors and Milky Way glow. Around Earth, J2000 directions rotate into the equator-of-date frame; Beyond Earth uses ecliptic J2000, additionally rotated with Earth’s ecliptic azimuth in Webb’s rotating view. This is a distant reference sky, not a view with stellar proper motion, parallax or observer travel modeled.

Space landmarks are educational guides, not extra simulated bodies. Kuiper Belt rings outline its approximate main region. Oort Cloud wire guides illustrate uncertain inner-edge (2,000–5,000 AU) and outer-edge (10,000–100,000 AU) estimates, not detected surfaces. Crossing markers combine NASA’s event dates with the sampled Voyager trajectory; they do not model the changing shape of the heliosphere. Zooming to a landmark never advances the mission clock. Dated crossing-site markers belong only to the Voyager 1 replay.

• HYG v4.1 · David Nash / Astronomy Nexus ↗ — combines Hipparcos, Yale Bright Star and Gliese catalogs. Our adapted star catalog retains HYG IDs, J2000 directions, visual magnitudes and B−V colors for stars of magnitude 6.5 or brighter, excluding the Sun; missing colors use a neutral value. Data and adaptation: CC BY-SA 4.0. Archived v4.1 definitions and license ↗.
• NASA landmark references: Kuiper Belt · Oort Cloud estimates · Voyager’s termination-shock and heliopause crossings. Original summaries; no NASA endorsement implied.

Science is a shared endeavor. These researchers, missions and maintainers make this view possible.

• CelesTrak · Dr. T.S. Kelso ↗ — public GP/OMM active-satellite elements derived from US Space Force data. Snapshot & provenance · Usage policy. No per-visitor requests to CelesTrak.
• NASA Blue Marble ↗ — NASA Goddard Space Flight Center; Reto Stöckli, Robert Simmon and the MODIS science teams. Earth surface texture. NASA imagery; no endorsement implied.
• NASA/JPL Horizons ↗ — spacecraft ephemerides. Distance snapshot · Voyager & planet samples, source metadata, query URLs and interpolation checks · Horizons methods & limitations. Voyager’s later solution: R. Jacobson, 2022, using DE440. NASA Voyager 1 mission history and milestones.
• Astronomy Engine · Don Cross ↗ — Sun, Moon and heliocentric planetary calculations, v2.1.19. MIT license. Closed orbit guides use its solar mass product and two-body orbital geometry. NASA/JPL planetary physical parameters supply approximate equatorial radii; rendered globes are enlarged and not scale comparisons.
• satellite.js contributors ↗ — SGP4/SDP4 propagation, v7.1.0; based on the Vallado implementation. MIT license & credits.
• Babylon.js contributors ↗ — rendering, v9.27.1, Apache 2.0. esbuild bundles this application; MIT license.
• Institute of Physics · the Pascal-B steel plate ↗ — historical context for the hypothetical; no verified spaceflight claim.
• NASA · Parker Solar Probe ↗ — verified solar-relative speed context.

Space stories · further reading

Original educational summaries, with credit to NASA and ESA. Each story links to its source. These are background science, not live hazard reports or an endorsement.

• NASA · Gravity & mechanics
• NASA Earth Observatory · Satellite orbits
• NASA · Spacecraft electrical power
• NASA · Webb questions & answers
• NASA · Webb’s orbit around L2
• NASA · Micrometeoroids & orbital debris
• NASA · A real station avoidance maneuver
• ESA · Space debris questions & answers
• ESA · Reducing space debris

A journey through scale

Pulling back beyond the Oort Cloud opens the full Milky Way–Andromeda encounter. First entry into Galaxy uses 1.5 million years per second so the stars visibly move; later visits retain your chosen Galaxy speed. Earth and the planetary orrery retain their own speeds. Each view keeps its own date; returning from an encounter restores Earth’s, the orrery’s or the mission player’s valid date and speed rather than moving satellites billions of years forward. Live Earth resumes actual UTC.

Sol marks an illustrative arm location attached to a model stellar tracer, not an accurately placed star or a prediction of the Sun’s orbit. The first arrival frames both galaxies with the Milky Way in the foreground. The pullback is a camera effect, not a spacecraft trajectory, and zoom itself never advances the timeline.

NASA · our galactic neighborhood · NASA / Spitzer · the Orion Spur and Milky Way structure. The Oort Cloud’s estimated outer extent is not a sharp measured boundary; our zoom threshold is a navigation choice.

Preset references

These sources remain available regardless of which simulation you are exploring. Missing black-hole measurements in curated presets are replaced by explicitly invented model masses, not claimed detections.

Custom galaxies and pairings are user-created experiments. Catalog-based builds use the global 50MGC and black-hole-scaling references above; their encounter trajectories are invented.

Physics & black holes

Hernquist-style halo potentials and Chandrasekhar-style friction are simplified here, with massless stellar tracers and softened gravity. Foundational references explain the ideas, not a validation or calibration of this implementation. The separate Black Hole Lab is a Newtonian experiment, not a relativistic simulation. Galaxy core coalescence does not establish a black-hole merger.

Space-story references

Educational background for the built-in stories. Individual cards link to the relevant source; model-specific notes refer to About in the simulator. Hypotheticals are labeled “What if?” and are not scientific forecasts.