My lord in an attempt to answer your question I have referenced all that can be mustered from the great Libratorium. It is known that in the early days of the great crusade contact was made with the Forge World we have come to know as Phaeton. Lying to the galactic southwest of Holy Terra Phaeton resides in the sector we know as Totradus in one of the three systems which make up Sub-Sector Thul. It is noted quite heavily that the priesthood of Phaeton refused all visitation to their home world at the time of its discovery claiming fear of instability within their system[see attached History of Warp Storms in Sector Totradus] and preferring to meet in the closest system of Thul on the World of Tahnel.
It is noted in the early logs that exploration in the sector was delayed immensely by violent warp storms causing issues with and the destruction of many warp routes, some of which still lost to this day. The most known of being in Sub-Sector Herodion much of which has been quarantined to prevent further loss. At the present with the exception of the previously mentioned Sub-sector most of these have cleared in the past ten millennia. This includes the massive storm system that separated Sub-sector Totradus from the newly discovered Sub-sector Amissum which is now in the process of vast terraforming practices. The rest of sector Totradus appears to have been enveloped quite unremarkably into the Imperium of man. It houses an average number of Hive Worlds the two most productive being the worlds of Gaios Prime and Totradus IV respectively, as well as the recent indoctrination of the planet Iona into a home world for the Adeptus Astartes of the Knights Crimson. None of this strikes me as very relevant to your question or perhaps more than what you already know.
The accounts of interactions with Phaeton are quite lacking to say the
least with only reports of the Ordo Machinum appearing to have been
granted access of visitation since the first discovery of the world. At the time of the Great Crusade it was regarded as the second most productive Forgeworld, second only to Mars itself and their rivalry began to grow as only one could imagine, which appears to have culminated unto a power dispute between the two. Rightly so, Mars feared Phaeton's unusually vast military force they had begun to
muster and saw this as the beginnings of a possible secession. In an attempt to control the power of all those that the Imperium relies upon Mars demanded a tithe, one that would effectively neuter the priesthood of Phaeton's power. There is little in the way of recorded communications still accessible but those that remain are riddled with barely veiled threats from both sides. The priesthood of Phaeton vehemently claimed superiority at being wholly committed to the Omnissiah and all that he demands and both sides are noted as massing their forces at this time. In the end as you know Phaeton agreed to send their tithe and curbed what could have been the first galactic civil war. The tithe however was cast out into the ether and would never arrive to Mars, it would settle on the world of Altar Median which was quickly converted into the Forge World it is known to be this day. The last communication recorded between Mars and Phaeton regarding this simply states "To he that is Omnipotent and no other shall Phaeton bend its knee."
Soon the Great Crusade was ground to a halt by the Arch Traitor, by the end of the great war both Phaeton and Mars were left trying to rebuild all that had been lost. Phaeton sunk in to the background of worries that began to build on Mars's Priesthood and eventually Phaeton was hardly thought of at all. Its great forges were perhaps retired as it slowly came to a more controlled production and output. Regardless, Phaeton now seems to have lost its rank amongst the many worlds of the Omnissiah. Production levels while still high for a planet match that of some of the smallest Forgeworlds known to exist.
I write to you now my Lord as I believe I see what you are asking. I have not been allowed passage to Phaeton but even from this orbital station I can see your fears are not without cause. Phaeton is like a scar in the night sky. Its darkness only illuminated by the flames of the countless forges upon its surface. Its three moons hang in unnatural orbit around it, turning in sequence with their host. I have not done the calculations and I do not know how it would be possible but the planet seems to be the gravitational center of its system. The two burnt orange stars always shinning on opposite ends. I have managed access to but very few of their records, the oldest already frightening enough. They call these stars "Draco Est Bestia and Draco Ex Sanguine". Literal translations being the Dragon of the Wild and the Dragon born of Blood. While I am frightened by what the second one could potentially mean, I am most distraught with a discovery of my own accord. I have been on this station for six months, I have watched this abomination of science and machinery turn slowly every day. There is no night on Phaeton and its great forges never sleep.
-Your humble servant