A black hole you can only see by what it bends
hold to gather gas under your hand and let go to drop it in · throw it past the hole and it is torn into a stream · click the hole and it rings · click the disk to light a hot spot · click the dark to drop a lantern and watch its clock slow as it falls in · catch it and throw it and it orbits · double-click the dark to call a comet, a pulsar, a planet or a star in · drag to swing round the hole · rest your hand on it and a star drifts in
A black hole, drawn the only way one can be seen: by what it does to the light around it. Nothing in the frame is the hole itself. It is a shadow where no ray comes back, rimmed by a thin ring of light that went round it before it reached you, and the winter sky behind it is bent into arcs and pulled into a ring: Orion, with the nebula in his sword exactly behind the hole, wrapped round it and seen twice. Its disk of hot gas lights from the inside out, its gas spiralling off the inner edge into the dark, and because light is bent over the top of the hole, the disk's far side is seen standing above it and its underside curled beneath it; the side turning toward you burns blue-white and the side turning away sinks to orange. The eye circles it, turns onto the shadow's edge and zooms in until the thin ring opens into the light that went round the hole once and, against it, the light that went round twice, climbs over its pole to look down into the ring, falls toward it until it hovers at the edge where light itself can orbit and the sky is squeezed overhead, and pulls far back to see it small among the stars. Things keep coming to it: a comet, pushed out from the hole by the disk's light into a tail, breaks into a string of pearls that whirl round it and fall in one by one; a pulsar falls in whole, its beams sweeping past you so that each of its images blinks on its own beat, slowing as it goes; a planet, lit only by the disk, crosses in front of it as a dark disc with a thin lit crescent, and breaks near the edge into rubble whose lit faces are strung round the shadow as it passes behind; and a gas giant is stripped of its banded air in a glowing stream, its core going on alone. Drag to swing round it, and every star in the frame slides through the bend. Tap the dark and a lantern falls in, blinking ever slower, and is never seen to arrive; catch it and throw it, and it goes round before it falls. Double-tap the dark to call something in.