A universe explorer built from real astronomical data.

Travel from the solar system to nearby stars, deep-sky objects and the observed cosmic web. Space Time brings astronomical catalogs, telescope surveys and computed motion into one navigable view.

Free · no download · no account

2.5 millionmapped stars
32,000+deep-sky objects
9,000+tracked satellites
630,000+DESI galaxies

Search for an object, go there, and keep moving.

What Space Time does now

Move through every scale in the same view.

Distance determines which objects become visible. The same controls, selection and time system remain available from planets to large-scale structure.

Continuous scale

From the solar system to large-scale structure

Planets give way to nearby stars, the Milky Way, galaxy clusters and the observed cosmic web as the camera moves outward.

Resolved destinations

Observed structure replaces anonymous glow

Andromeda includes 2,753 Hubble PHAT cluster positions. The Coma Cluster resolves into named catalog galaxies, while stellar clusters use measured Gaia members.

A moving star catalog

Stars change position when the clock moves

Measured Gaia and HYG proper motion moves 411,954 stars through the same three-dimensional scene. Radial velocity is included only for stars with a catalog measurement.

Catalog galaxies at physical distance

Go to galaxies beyond the curated landmarks

Catalog galaxies with usable redshift data now become physical destinations. Direction, distance, dimensions, position angle and morphology come from the catalog; generic close-range structure is identified as a reconstruction.

Dated observations

See which atmosphere was actually observed

Jupiter, Saturn, Uranus and Neptune can use archived Hubble OPAL maps. The observation epoch and filters are shown; the app does not pretend an old image is a live forecast.

Three-dimensional evidence

Enter a reconstructed supernova remnant

Cassiopeia A, the Crab Nebula and SN 1987A are physical destinations built from published three-dimensional evidence, with analytical context identified separately.

Survey imagery

Open real observations in context

DSS2, HiPS and selected observatory images are placed at their catalog coordinates. Open an observation, identify its target and continue moving through the scene.

Surface view

View the sky from other worlds

Land on a planet or moon, change the time and select objects in the local sky. Return to space without losing your place.

Relativistic travel

Compare the clocks during a journey

Choose a destination and see the travel time, the time elapsed at the departure point and the time experienced by the traveler. The calculation and its assumptions are shown.

Galaxy environments

Identify galaxies inside a cluster

The Coma Cluster includes its central giants and named spiral members at catalog positions, surrounded by a restrained statistical faint-member population.

Live data

Current Earth, Sun and observing conditions

Current satellite imagery, solar activity, aurora, weather and visible targets are available inside the main view.

Observing tools

Plan for the sky above you

Use your location, weather, equipment and the Moon to find worthwhile targets, then identify them in the live sky.

Galactic dust and gas in 3D Complete exoplanet systems Binary stars and pulsars Real cluster members Hubble-dated giant planets Clock-driven planetary seasons Measured spatial stellar motion Redshift-resolved catalog galaxies Resolved supernova remnants Surface terrain and sky Mission trajectories

Recorded in the app

Recordings from the live model.

These are screen recordings from Space Time itself. No stock footage and no rendered cutaways.

Measured stellar motionLinear propagation of Gaia and HYG catalog velocities from 2026 to 7026 in exact 60 fps engine frames.
Earth to the Coma Cluster323 million light-years in one continuous journey.
Saturn and its ringsExact 60 fps engine frames from the live 3D scene.
Sagittarius A*Gravitational lensing at the galactic center.
Filaments and galaxy clusters in the mapped local universe

Where it comes from

Sources and limitations are shown in the app.

Space Time combines catalogs, survey images and physics-based calculations. Reconstructions and visual exaggerations are identified in the interface instead of being passed off as observations.

Solar system
JPL-derived ephemerides and Horizons trajectories
Stars
Tycho-2, HYG and Gaia positions and measured motion
Deep sky
DSS2, HiPS, Hubble and catalog distances
Universe
2MRS, DESI DR1 and Planck observations
Live
NASA, NOAA, TLE and weather feeds
Check the model yourself

Before you open it

Common questions.

Is it really free?

Yes. You can explore without an account, subscription or download.

Can I really fly from a planet to a galaxy?

Yes. Planets, stars, survey-backed deep-sky objects, galaxies and large-scale structure share one navigable environment.

Is every part a direct observation?

No. Positions and images come from real sources where available. Some paths, surfaces and invisible structures need reconstruction or visual scaling, and the app says so.

Can it tell me what is visible tonight?

Yes. Set your location to see rise and set times, weather, lunar interference, telescope framing and a ranked list of targets.

Does it work on a phone?

Yes. The interface adapts to phones and tablets and includes a device-orientation sky compass.

Nothing to install

Open Space Time.

Free to use, with no account required.

Open Space Time