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Rules > Starship > In Atmosphere
Starfinder Starship Operations Manual p.52
Whether the steamy air of Castrovel or the breathtaking clouds of Bretheda, all atmospheres consist of gases that generate large amounts of heat when objects—such as starships—pass through them at incredible speeds. While a starship’s shields can often protect it from everyday amounts of friction, it is nevertheless unwise for starships to accelerate to the point where this protection is insufficient. Beyond this common threat to a starship’s integrity, other types of atmospheric hazards require a deft crew to negotiate without the ship suffering dangerous conditions and effects.
Atmospheric friction can quickly tear apart starships of even the highest
tier, and it is as dangerous to small, lightly armored starships as it is to
massive warships. The amount of friction generated by a starship is determined
by the friction level of the layer of atmosphere that the starship is traveling
through. An atmosphere’s friction level is an abstraction of the atmosphere’s
density and the amount of debris in the air.
For the purposes of this system, atmospheres have five distinct layers, classified by similarities in temperature and density. While the names and exact properties of these layers vary on different worlds, an atmosphere’s layers generally become denser the closer one gets to a planetoid’s surface. The greater an atmosphere’s density, the slower a starship must move through it in order to avoid taking damage from friction between the starship’s hull and the atmosphere’s molecules. Table 2–7: Atmospheric Friction summarizes the effects of atmospheres based on the thickness of each of the atmosphere’s layers; “highest” refers to the layer furthest from a planetoid’s surface while “lowest” refers to the layer closest to a planetoid’s surface.
When a starship moves faster than its maximum safe speed in an atmosphere layer, it takes Hull Point damage equal to the starship’s tier × the atmosphere’s friction multiplier for every hex moved that round beyond the starship’s maximum safe speed (see the below table for these calculations). This damage is dealt to the starship’s forward quadrant.
|ATMOSPHERE LAYER||MAXIMUM SAFE SPEED||FRICTION MULTIPLIER|
When present during starship combat, a significant hazard might shape the outcome of the battle. As a result, the GM might decide to award PCs additional XP for surviving such a starship combat, granting the PCs XP as if they had beaten an encounter one step more difficult than represented by the challenge level (Core Rulebook 326).
In addition to friction, some atmospheres have unique properties that present additional challenges. The GM determines which hazards, if any, are present in a given hex. These conditions can permeate the entirety of a planetoid’s atmosphere, or they might be limited to specific regions. The GM should determine the prevalence of each hazard based upon the unique properties of each planet and its weather patterns, if it has any. Hazards should be played out in starship combat mode.
Particularly alien atmospheres sometimes have properties that cause them
to eat away at a starship’s hull, bypassing any shields that the starship might
have. Examples include corrosive atmospheres, atmospheres with extreme heat
or pressure, or even atmospheres that precipitate jagged shards of silicon at
velocities sufficient to slice through a starship’s hull.
Each time a starship moves through a hex containing a damaging atmosphere, it takes Hull Point damage equal to its tier. This is in addition to any damage the starship takes due to friction.
Oftentimes atmospheres become charged with electricity as the atoms that make up atmospheric gases transfer electric charges between one another, resulting in deadly bursts of lightning. At the end of each helm phase, the GM rolls d% for each starship to determine whether lightning strikes that starship. The chance that lightning strikes a starship is determined by the hazard’s severity (see Table 2–8: Electric Storms). If a lightning strike occurs, the starship’s pilot must attempt a Piloting check to avoid the hazard (the DC is determined by the hazard’s severity; see Table 2–8). If the pilot fails the check, the starship takes damage equal to 1d6 × the starship’s tier. This damage is dealt to a random quadrant of the starship (roll 1d4: 1—forward; 2—port; 3—starboard; 4—aft).
Frigid atmospheres can generate ice crystals when water droplets in the atmosphere
contact a solid object, such as a starship. In sufficient quantities, this results
in key systems of the starship rapidly freezing over. At the end of the helm
phase, a starship’s pilot and science officer must each attempt a skill check
(Piloting for the pilot, Computers for the science officer). The DC for this
check is determined by the hazard’s severity (see Table 2–9: Ice Storms).
If the pilot fails their check, the starship’s engines are glitched until the end of the next helm phase. This increases to malfunctioning if the pilot failed their check by 5 or more, or wrecked if they failed by 10 or more.
If the science officer fails their check, the starship’s sensors are glitched until the end of the next helm phase. This increases to malfunctioning if the science officer failed their check by 5 or more, or wrecked if they failed by 10 or more.
Atmospheres often interfere with a starship crew’s ability to perceive the area they’re flying through, usually due to cloud coverage, precipitation, atmospheric density, or unusual weather patterns. An atmosphere with the obfuscation hazard imposes a penalty on gunnery and Piloting checks, as well as on Computers checks that use the starship’s sensors. This penalty is determined by the severity of the obfuscation (see Table 2–10: Obfuscation).
Atmospheres that are inherently toxic normally pose little danger to a starship’s crew, as a starship’s life support systems include pressure-sealed interiors that keep atmospheric toxins at bay. But a compromised system increases the chance that a toxic atmosphere will affect a starship’s crew. At the end of starship combat, if a starship is flying in a toxic atmosphere and its life support systems have a critical damage condition, roll d% to determine whether the toxic atmosphere affects the starship’s crew. The chance that this occurs depends on the severity of the critical damage condition, as follows: glitching—25%, malfunctioning—50%, wrecked—90%. All breathing creatures within the starship are affected by the atmosphere’s toxicity as normal (unless they have protection, such as from environmental protections from armor or the benefits of life bubble).
Atmospheres are ever-changing, ever-moving environments in their own right, capable of wreaking havoc upon the plans of even the best starship pilots. When piloting in a windstorm, a starship’s pilot attempts a Piloting check at the beginning of the helm phase to navigate the treacherous currents. The DC of this check is based on the storm’s severity (see Table 2–11: Windstorms). If the pilot fails this check, the starship’s speed is reduced by half and the distance it must move before turning increases by an amount based upon the severity of the windstorm (see Table 2–11); both effects last until the end of the round. In addition, regardless of the result of the check, at the end of the starship’s movement, the GM rolls 1d6 and compares it to the starship’s current facing (roll 1d6: 1—forward; 2—forward-starboard; 3—aft-starboard; 4—aft; 5—port-aft; 6—forward-port). The GM then moves the starship 1 hex in the resulting direction.