This immature Yggdrasil Bush only covers a fraction of the planetoid it is growing on; eventually the canopy will cover the entire object, and only then will the plant release atmospheric gases
Nonsentient lifeforms, plant- or fungal-based, neogen, or xenobiont organisms which have evolved or been designed to survive in space at a given orbital zone and radiation level.
Designed examples include Dyson Trees, AmatFruit, GreenBubbles, OxyFruit, HydroFruit, and LifeFruit. Term derived from 'astra' (star) and 'genus' (life form). Xenobiont astragens include the various species of space amoeba, which may themselves have been designed or modified by ancient and/or extinct xenosophonts.
HydroFruit - Text by John B Astragen capable of producing purified water from contact with oxygen and hydrogen bearing materials. Often used in Oort-belt dispersals, in which case the organism will occasionally be designed to exude ice particulates.
LifeFruit - Text by John B Generates ATP (adenosine triphosphate, a basic biologic energy storage molecule), but is one of the more power-hungry forms of astragen. LifeFruit typically requires earth-type solar energy levels.