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Astrophage is an alien microbe, which acts similar to an interstellar mold or algae. It grows upon the surface of stars, decreasing the brightness and leading to a dramatic decrease in temperature of any celestial bodies in orbit of the affected star. This will lead to a mass extinction on any planets with life in the affected star's system. It can travel from star to star. It originated from the star system Tau Ceti and went on to infect many more stars afterward, namely Sol and 40 Eridani. Astrophage can travel a maximum of 8 light years from its infecting star in spore form.

Life Cycle[]

Astrophage absorbs energy from the closest star (e.g., Sol). Once it's "enriched" (i.e., it can store no more energy), it travels to a planet with lots of carbon dioxide. In the case of Sol, it travelled to Venus. For Tau Ceti, it travelled to Adrian. For 40 Eridani, it travelled to Threeworld. It uses carbon dioxide to reproduce and then both the parent and child cells travel back to the closest star to begin the process again.

Uses[]

Astrophage has nearly limitless scientific and engineering applications, which leverage one or more of the following characteristics:

Energy Storage[]

Using Neutrinos and a form of pair production, Astrophage is capable of storing massive amounts of energy by converting energy directly into mass, later converting this mass back to energy as Petrova-frequency IR light.

This effectively makes Astrophage the most efficient possible energy storage system in the universe, converting energy into mass and back with no measurable loss.

An Astrophage is said to be "enriched" once it reaches its maximum energy capacity - roughly 1.5 million joules in a single cell.

Propulsion[]

Astrophage propels itself through space using Petrova-wavelength IR light, which can be leveraged to propel a spacecraft.

The Hail Mary utilizes "spin drives" to leverage Astrophage propulsion for space travel. A spin drive uses a three-phase cycle to achieve this: first, it attracts Astrophage fuel to coat one side of the transparent triangular drive mechanism using low-intensity light with wavelengths of 4.26μm and 18.31μm (peak frequencies of the CO2 emission spectrum); then rotates the now coated surface to be exposed to space and emits high intensity light of the same frequencies to cause the Astrophage to "push" against the slide, imparting momentum to the craft; and finally the slide is rotated back into the engine housing where the now "dead" Astrophage is scraped off to allow the cycle to repeat.

The Blip-A is also stated to use Astrophage for propulsion, though the specifics of its engine technology are not discussed.

Heat Sink[]

Via a combination of its lifecycle and an effect referred to as "super cross-sectionality", an Astrophage cell will always remain at 96.4 degrees Celsius when alive. Any excess heat above this level, even on the surface of a star, is absorbed by the Astrophage cell and converted to mass. Conversely, if the cell begins to lose heat, it will expend some of its internal mass-energy reserves to maintain the 96.4 degree temperature.

This makes Astrophage an incredible heat sink for temperatures above 96.4 Celsius, as well as a heat source for environments below this temperature.

Several of Rocky's inventions take advantage of this characteristic of Astrophage. For example, his "environment ball", which he used when first boarding the Hail Mary used a small quantity of Astrophage to act as a heat sink for the heat expelled by his "hot" circulatory system via his "radiator organ".

Radiation Shielding[]

Also owed to it's "super cross-sectionality", which prevents all light and even Neutrinos from penetrating its cell membrane, live Astrophage can also be used to block radiation. The Hail Mary has Astrophage in a thin layer around the crew section of the ship, in part to act as a barrier to interstellar radiation and protect the crew within.

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