Stardust mold is an extremophile mold that can survive, and even thrive in the vacuum of space - deriving energy from radiation and unfiltered light from stars. It is occasionally found on the outer hull of starships, although collecting it and cleaning it off requires a suited spacewalk. When prepared correctly it can be absorbed through the skin and has a strange chemical effect on cerebro-spinal fluid or equivalent substances. The mold causes neurological fluid to become more viscous, and also imparts some energy absorbancy, reducing damage from head injuries or stun weapons.

The exact initial source of Stardust Mold is unknown. It was first identified and described on the hulls of ships in the Polaris Sector around 1700PT, and has since spread to become a ubiquitous part of the flora found on starship hulls across known space. IT is theorized that the mold was once part of a colonized planetary ecosystem, and “hitched a ride” on starships landing on its homeworld. Due to its metallic appearance and small colony size, it may well have gone unnoticed for decades, and spread to other starships during docking procedures. As such, the exact homeworld of Stardust Mold cannot be pinpointed to any degree of accuracy, and similar molds have not been encountered in any known colony in the Polaris Sector.

Stardust Mold is unicellular fungus that forms loosely interconnected colonies, usually no more than 1-2mm in diameter. Colonies are formed when spores alight on a ceramo-metallic surface, and use small quantities of the underlying hull substrate to replicate into a stable colony of several thousand cells. Energy is derived from absorbtion of electromagnetic radiation, mostly in the visible spectrum, but with a proportion in the near-ultraviolet. Once a colony reaches its mature size, the cells form specialized fruiting bodies that gradually produce spores to create new colonies, pushing individual spores away from the host colony with minute cilia. Spores tend to travel only a few metres before the gravity of local objects (usually the same starship host as the original colony) pull them onto a new substrate, where the process begins again. Nearby established colonies (within about 10mm) emit chemical signals that induce both colonies to grow fine cilia allowing a degree of connection and nutrient sharing.

Although usually considered to be harmless, stardust mold can reduce the effectiveness of photovoltaic cells and other solar energy sources that rely on radiation. The amount of material used in colony formation barely penetrates the outer few microns of hull, and is usually of no significant concern over the lifetime of a starship.

Stardust Mold's defining feature is its extreme resistance to the cold and radiation of deep space - although it grows extremely slowly and possesses few other advantages in a competitive biosphere - in space it is king, able to survive conditions that would instantly kill most competing organisms. Its hardiness is derived from its durable DNA, ability to self-repair and incorporation of dense metallic ions in its external walls. Each cell is relatively independent within the colony and is capable of rapidly repairing any damage caused by ionizing radiation. Mold cells possess internal organelles that deploy what are effectively “DNA backup” enzymes, which restore damaged genetic material. These organelles are themselves shielded from damage by a heavy metallic coating, which blocks most of the harmful particles. The mold cells themselves are filled with a cytoplasm with a very low water content, which contains numerous chemicals that prevent freezing.

Harvesting Stardust Mold sustainably is a delicate process, as the individual colonies are quite fragile, and their sporing rate is fairly slow. Vacuum-based methods do not work in an airless environment, so brushes are required to loosen them from the surface. A colony's grip on the underlying hull substrate is fragile, and in microgravity it is relatively easy to brush more than half of the colony's cells into space.

In order to be useful, Stardust Mold must be treated to harvest its specialist organelles, which are the part of the plant that provide its useful neurological properties. Sustained immersion in a mild aqueous solvent slowly softens the outer cell walls over the course of about a week. After the outer walls have softened and the cells have absorbed a large volume of water, the cell components can be separated in a centrifuge to extract the organelles. These can be suspended in a mixture of enzymes to allow them to be absorbed through the skin and delivered to the primary neural systems.

After a period of a few hours, the host's body will overcome the effect of the organelles, and return their cerebro-spinal fluid to its normal composition. Stardust Mold is best administered prior to an excursion where its effects are likely to be needed.

Stardust Mold is a type of Exotic Biotic - an Exotic Substance related to Life Science. A physrep of a small vial of fine coloured powder can be used to represent a few measures of this substance, but particularly large physreps can hold more.

When applied to a character, a measure of Stardust Mold grants them a single additional rank of the Steel Head skill, reducing the duration of KNOCKOUT calls that they are affected by.

As with all Exotic Substances, a character with at least 1 rank in the relevant speciality (Life Science in this case) can spend 1 minute of appropriate roleplaying to apply 1 measure of Stardust Mold to a character or item. After this roleplaying, they should unpeel the sticker that represents this substance, stick it to the target's character sheet, and record the current date and time on it.

The protection provided by this substance wears off two hours after it is applied.