Mission to Anywhere

Planet positions come from JPL's published orbital elements and are right for today's date. Star positions, distances and colors are real, from the AT-HYG catalog, and the exoplanets are real discoveries from NASA's archive. The transfer orbits and the relativity math are the true equations, but the galaxy backdrop is an illustration, exoplanet positions along their orbits are not known, and nobody knows how to build a ship that holds a steady push like this for years. Star sizes on screen show brightness, not true size.

About 110,000 real stars are charted here; 10,000 of them are clickable, along with a few hundred named objects far across the galaxy. As you pull back the faintest of them thin out so the view stays smooth, and they come back as you zoom in. Star close-ups are procedural art driven by each star's real temperature, size and type; the flares and the surface detail are typical for the type, not observations. The eight planets of our own system are drawn the same way, as likenesses of worlds we do have real pictures of. Every exoplanet orb is an impression drawn from its measured size and temperature, and nobody has seen any of them up close. In the cockpit view the dust streaks are invented motes, but the way the stars crowd forward and shift color is the real aberration and Doppler math at the speed shown on the HUD.

The galaxy itself is a painting. Its shape, its size and the Sun's place in it are real, but nobody has ever seen our galaxy from the outside. The stars drawn on top of it, about 110,000 of them, are real stars at their real measured positions, and almost all of them are within a few thousand light years. The handful of objects farther out are the ones astronomers have individual distances for.

A few thousand light years from home the map thins out. That is not because the stars end. Dust between us blocks the view, and the simple one-over-parallax distances in this catalog stretch by five to fifteen percent out there, and by much more beyond that. What is charted individually on the far side is a few hundred beacons: pulsating stars measured in the infrared, and gas clouds measured by radio telescopes linked across the planet. Those are the ones you can visit here. The ordinary stars over there are not on anybody's map with a distance you could fly to.

Those far objects are drawn as markers, never as discs. A globular cluster is a swarm because that is what it is, the Magellanic Clouds are soft patches whose shape is an impression, and the black hole at the center of the galaxy is drawn as the sky bent around it, because it has no surface of its own. None of them carry a temperature, a size or a color here, because nobody measured one.

Up close at Sagittarius A*, the stars circling it are on their published orbits and at their measured positions for today, which is the one place on this page where where a body sits on its orbit is a measurement rather than an illustration. The bending of light around it is computed from the real geodesics for a non-spinning hole of that mass, but the marker is drawn at a fixed size on screen: from the parking distance the shadow itself would be far smaller than one pixel. Some more of the honest small print for that place:

The glow around the real Sgr A* is famously faint; it shines at less than one hundred-millionth of what a black hole its size could. We draw it faint. The brighten switch is for drama and says so.

The famous orange ring photo is radio light, not what eyes would see.

Nobody knows how fast it spins; the two best methods disagree. We draw the non-spinning case.

The background sky here is our own star catalog. The real view from the galactic center would blaze with millions of bulge stars nobody has catalogued for us. The soft glow standing in for them is an illustration, like the painted galaxy: it is brightest along the real plane of the galaxy, but not one point of light in it was measured.

The two teams that weigh this black hole disagree by about seven percent. We use the newer interferometer number.

The background star tier is a separate file of up to 100,000 stars, about 1.07 MB on disk after base64, loaded only after the page has drawn its first frame. If it never arrives the map still works.

The four-point crosses on the brightest stars are a camera effect. Real starlight has no spikes.