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Very little has been revealed about the nature of the Aphelion, but it has been stated that they are extremely dangerous, malevolent and stealthy. They have claimed the lives of many Awoken, including the inhabitants of the RSS Amestris and three Techeuns. Sjur Eido is the only Awoken known to have survived an Aphelion attack.
Paladin Pavel Nolg reported seeing a "glowing creature" on the exterior of his ship Retribution shortly before executing an NLS jump; this sighting was filed along with the Amestris incident as being related to the Aphelion.
They appear to be extremely radioactive, a trait which apparently led one Awoken on the Amestris to draw a connection between the Aphelion and an apocryphal story about the fissioneers of the Distributary.
In the Chronicon, the Loyalist Scribe Shagac refers to the Aphelion as a predator with "the power to devastate whole worlds in the blink of an eye." Information regarding the Aphelion and its abilities is apparently kept within Athenaeum World X.
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