A browser game · single pilot · orbital debris clearance

KesslerCascade

One collision makes fragments. Fragments make more collisions. Clear each orbital shell, refit your ship, and climb before the cascade closes the sky for good.

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13ship refits4kinds of debris4bosses0installs
Past a certain density, debris in orbit makes its own debris. Every impact seeds the next.
The premise is real

In 1978 NASA scientist Donald Kessler described how a crowded orbit could tip into a chain reaction of collisions. The idea carries his name: Kessler syndrome.

Kessler Cascade hands you the cleanup job. It takes the bones of the 1979 arcade classic, a ship, inertia and rocks that split, and builds a modern run-based game on top.

How it plays

Thirty seconds to learn. A long climb to master.

A volatile rock detonating beside the ship, with gold ore and ice debris drifting above the Earth's limb.

Set off the cascade

Ember-veined debris detonates when it breaks, and the blast takes its neighbours with it. Line up a chain and the whole field goes in one move. Stand too close and so do you.

The ship firing on the Warden, a ringed machine throwing out a circle of pink rounds.

Dash straight through it

Press Shift to phase dash. For a moment nothing can hit you, and any rock in your path is rammed apart. It recharges in under three seconds, so use it often.

You will need it on shell 5, where the Warden waits with rings of fire and an enraged second phase.

The Bolas boss: two armoured pods joined by a bright beam, sweeping across the field high above the Earth.

Mind the beam

The Bolas guards shell 10, the geostationary belt. Two armoured pods are tied together by a beam that sweeps the field and reverses without much warning. Shoot the pods. Dash through the beam.

Know your debris

Four kinds of rock. Four ways to deal with them.

These are the live models from the game, tumbling in the same light.

  • Rock

    Splits in two, then two again. The bulk of every field.

  • Ice

    Shatters into three fast shards. Hit it from range.

  • Ore

    Tougher than rock, and the best source of power-ups.

  • Volatile

    Explodes when destroyed. The start of every cascade.

The climb

Every shell is a real altitude.

You start at 400 km, where the space station flies, and work outward. The Earth below shrinks with each shell, sized from the true geometry, and it drifts past at orbital speed.

At 35,786 km it stops moving. That is geostationary orbit, where a satellite keeps pace with the ground.

Beyond shell 10 lies graveyard orbit, and the shells keep coming.

  1. 400 kmStation altitude
  2. 550 kmConstellation shell
  3. 780 kmPolar crossing plane
  4. 865 kmFragmentation field
  5. 1,200 kmUpper constellation shell
  6. 1,400 kmLong-lived debris band
  7. 2,000 kmEdge of low orbit
  8. 8,000 kmInner radiation belt
  9. 20,200 kmNavigation shell
  10. 35,786 kmGeostationary belt
  11. 42,000 kmGraveyard orbit
  12. 55,000 kmDeep debris field
  13. 72,000 kmOuter sentinel ring
  14. 90,000 kmCislunar crossing
  15. 120,000 kmFar scatter belt
  16. 180,000 kmDeep space threshold
Refit between shells

Clear a shell, choose one of three.

Refits last the whole run and stack with each other and with the timed power-ups that drop in the field. No two builds end up the same.

    Controls

    Keyboard, touch or gamepad.

    Keyboard

    Turn
    ← → or A D
    Thrust
    ↑ or W
    Fire
    Space
    Dash
    Shift
    Pause
    P
    Sound
    M

    Touch

    Steer
    Drag anywhere
    Thrust
    Drag further
    Fire
    Hold Fire
    Dash
    Tap Dash

    Gamepad

    Steer
    Left stick
    Thrust
    Left trigger
    Fire
    A or right trigger
    Dash
    B, X or a bumper
    Pause
    Start
    Shell 01 · 400 km · the field is waiting

    Clear the sky.

    Play Kessler Cascade

    Plays in your browser with nothing to install. Best with sound on.