The Lux Aeterna is a sight in the Hypersea caused by two orbiting black holes. These black holes orbit each other in such a way that their relativistic jets, in simpler terms beams of ionised matter spat out by them, directly hit each other. This has caused a Hyperdrive-like effect which manifests itself by the collision site tearing itself into Hyperspace so badly, that from Hyperspace one can directly observe the jets. Furthermore, the proceeding interaction with dark energy causes what us simpler folks can only describe as 'a wickedly awesome lightshow'.
With large parts of the Hypersea being boring colour-wise, and sensory horizons being a thing, one cannot underestimate how Stormfarers feel about the Lux Aeterna. A spectacular lightshow that is noticable by the naked eye from a distance beyond where sensors can pick up other ships, providing a colourful backdrop that makes one want to write poems about it. Which unfortunately too many bad poets have done.
It gets even better for those with genetically selected Tetrachromacy, as to those the intensity of the colours are even deeper and more varied. Some have described it as looking into the eye of God herself. Approaching the Lux Aeterna even lets one witness how the black holes behind it tear and bend even Hyperspace and cause the light to blossom like a flower. It is beautiful, and at the same time terrifying, as it is a place where space and Hyperspace actively flow into each other.
Studying the unreachable
One cannot get too close to the Lux Aeterna, as the large gravity wells behind it cause Relativity to spike near it. Any ship getting too close risks getting thrown out of Hyperspace lightyears removed from the actual black holes. Furthermore, the constant waves and ionised blasts mean bouts of incredibly low Tranquility. One cannot even call it a storm, it is simply an agressive ocean bashing itself against cliffs. To sail near it is to dance between these cliffs that are ready to tear you apart.
So far no other places have been observed where normal space tears into Hyperspace. This has made the place an ideal observation point for scientists. It is rather common for a group of scientists to hire Stormfarers to get them and their sensors close, so they can try to make sense of the event. It is a risky but lucrative job, which unfortunately does attract the occasional scam artist.
One of the things scientists are trying to figure out by studying the Lux Aeterna up close, is what would happen once the black holes combine. Would the light cease, or would it start absorbing Hyperspace itself? And what, if anything, does that say about the supermassive blackholes at the center of galaxies? We know there is a place where three galaxies are dancing around each other, far beyond our sensor reach in Hyperspace. What would the Hypersea behave like around there? Would it be marvelous? Or would it cause a feeling of dread too great for a person to bear? Perhaps one day we'll find out. For now, all we can do is watch a sight so spectacular that it makes sailors weep.