Environments · Extraplanetary

Low Orbit

The orbital band a few hundred kilometers above a world, where a body circles in about ninety minutes and drag still matters. Every settled world has a shell of traffic, debris and hardware at this altitude, and the right to place objects in it is disputed.

Extraplanetary

Exposure

  • Vacuum

    No pressure and no air to breathe, with survival measured in rounds.

    • Countdown

      Without a seal, a creature holds out for a number of rounds equal to its Constitution modifier, minimum 1. At the end of that time its hit points drop to -1, unless they are already lower, and it is dying. It cannot be stabilized or regain hit points until it can breathe.

    • Decompressed

      Exposure inflicts the Decompressed condition, which a return to pressure does not by itself remove.

    • Holding your breath

      Holding a breath in vacuum ruptures the lungs. A creature that does so takes 2d6 damage on the first round and gains no benefit from the attempt.

    • Sound

      Sound does not travel. Verbal spell components, shouted orders and Perception by hearing all fail across open vacuum. Suit comms and touch are the only channels.

    • Unfiltered light

      Without air to filter it, the star's output arrives unreduced. An hour of unshielded exposure in direct sunlight counts as a failed Contaminated Atmosphere save against radiological dose.

  • Zero Gravity

    Free fall, where there is no down, no moving body stops on its own, and a missed handhold leaves a creature adrift.

    • Movement

      Moving requires a surface to push from. A creature with nothing in reach continues in the direction it last moved until it reaches something.

    • Changing course

      Changing direction mid-drift requires a DC 12 Dexterity (Acrobatics) check. On a failure the creature continues as it was.

    • Melee

      An unanchored melee attack has disadvantage and pushes the attacker 10 feet away from the target after it resolves.

    • No falling

      There is no up, no down and no falling damage. A creature cannot be knocked Prone, and the Prone condition does not apply.

    • Mag boots

      Magnetic boots or a tether remove every entry above while a ferrous surface is underfoot, at the cost of half movement.

In play

  • Orbital mechanics

    No object holds a position. Matching another object requires a DC 12 Piloting check. On a failure the vessel arrives on the next pass, ninety minutes later.

  • Line of sight

    The whole day side of the world is visible, and so is anything on it. Concealment from orbit requires overhead cover, and distance does not provide it.

  • Debris

    Fragments move at orbital speed. A vessel that stays stationary makes a DC 12 Piloting check each hour or takes 2d10 damage to the hull.

  • Ionizing dose

    Unshielded, a creature gains a level of exhaustion each hour. A long rest does not clear it. A Medicine check at DC 12, a restorative spell or antiradiation drugs remove it. Rated shielding removes the effect, and most powered plate raises the interval to four hours.

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