Just a little random universe building.
In the Epsilon sector is an A5 graded relic (little further analysis possible), the Engraved Moon.
A fairly unremarkable natural low-gravity satellite, the moon is tidally locked with it’s volcanic partner planet. It shows signs of some exploration, but little evidence remains. The vast proportion of the relic is in it’s planet-ward face, almost the entirety of which is covered with a massive laser-engraved image. The image itself is hard to decipher, but seems to show two unknown life forms interacting, with a background of non-sentient flora. It has been compared to the late Baroque style of Earth.
The significance of the image is unknown. For one matter, it is unfinished; the raster-rendering halting in the south-west corner with some small smearing that suggests violent interruption of the process. This is further supported by evidence of orbital gun platforms around the nearby planet, in the form of radio-actives and vaporised superconductors in defuse orbits of the Lagrange points.
There is also damage to the image from asteroidal impacts, determined through standard isotope scans to have originated from the cataclysmic impact of a larger asteroid with the primary planet some 700,000 years ago.
The core of the most popular theories is that the planet previously held a circa Class-0.7 civilisation that was in conflict with other members of it’s own race, which necessitated the construction of orbital weapons platforms. These platforms were re-purposed to try to deflect or destroy a ELE-grade asteroid, but were incapable of successfully doing so. The theory goes that realising there was no hope, one of the platforms was turned toward their moon to leave a lasting marker of the races existence by raster-engraving an image on it’s surface.
If this was indeed the case, it was a success as the impact sufficiently heated the planets crust as to initiate a new perpetual volcanic state. The entire surface is estimated to now fully renew itself every 4 standard years. No trace of former life on the surface has ever been found, nor is ever likely to be.
While of no remaining archaeological interest, the system does see infrequent tourist traffic. An extension of the theory has entered popular myth, embellishing it as a monument not to the civilisation, but as a final romantic act of a couple working on one of the gun platforms. The most consistent version sees the couple realising that death is at hand, and over-riding the useless firing attempts of the platform to immortalise themselves together, often dying in each-others “arms” as depicted in the image, as debris wipes out the platform.
This is of course massive assumption. The two figures could equally be locked in a final death-struggle; no other record of the race, it’s cultures or biology remains. But that it might be true is often more than enough for the die-hard romantics who take the long cruise out to see the Engraved Moon.