The Angel Sector is an area of barren space comprised of hundreds of identified stars which form a sphere-like mass. There is at least one known double black hole system within the sector. The planetary composition of the sector is unknown. None of the observed planets in the border systems appear to be inhabited or even capable of sustaining carbon based lifeforms.
Early report from Amalah space traveler indicated that the Angel Sector had been closed off since before they had achieved faster than light travel in 1870. For some time, Amalah ships had avoided a certain area of space after their crews became increasingly fearful, causing them to turn back as soon as possible. Initial disappearances of exploratory vessels were assumed to be accidents until enough occurrences prompted an investigation. Two ships were dispatched to locate the missing vessels but only one returned a week later. The surviving ship reported that upon entering the star system the crew had suddenly come under immense psychological pressure to turn back. Overcoming what they dismissed as paranoia, the ship continued pressing on, after which it began experiencing system failures one after another. After repairs, the ship again restarted its mission.
The ship was then engulfed in light and attacked by an unknown force. Witnesses said the attacks varied between the ship being crushed from the outside and torn apart from inside. The captain ordered the ship to leave the system before any more damage could be done.
Successive attempts to enter the sector met similar fates. After unmanned probes met with similar fates, Amalah deduced that whatever was causing the destruction was an intelligent life-form. Peace overtures were made; radio messages and samples of Amalah culture were repeatedly sent towards the planets thought to be the homes of this alien life. There was never a response. Eventually, Amalah forbade its citizens from entering the sector.
The exact boundaries of the Angel Sector were defined as other civilizations were met with similar circumstances over the years. The Dark Ages of 2788 to 2821 did not seem to affect the sector's ability to ward off unwelcome vessels. There are no records of any further attempts to penetrate the sector during this time but upon the stabilization of the galaxy, renewed attempts begun by the surrounding powers. The largest attempt was in 2829, when an Alchewistran invasion fleet of 35 ships attempted to traverse through the sector during a planned surprise attack on the Jiptohr capital world. The fleet was immediately beset upon despite attempts to fight back at their unseen enemy. Only 8 heavily damaged ships managed to retreat. Surviving ships did manage to obtain recordings of the attackers, confirming that there was some sort of intelligent life behind the sector's isolation. At slowed down speeds, there were glowing figures wrecking the ships from the inside. They appeared like featureless Jiptohri, but much taller. Their strength was immense, as they barehandedly destroyed the ships' interior.
Conversely, a severely damaged Jiptohr Empire ship that been forced to jump into the sector was visited by the same same light beings but allowed to make repairs before being afflicted with the usual effects the sector imposed on all ships. Some reports even say the light beings restored the ship's systems. Jiptohr credits the destruction of the Alchewistran invasion fleet as a turning point in the Jiphtohr Unification Wars, and the actions towards the lone Jiptohri ship as an act of mercy on the light beings part. The Jiptohr Empire from then on considered those that dwell in the Angel Sector as heavenly allies. Jiptohr has barred its citizens from the Angel Sector except to make annual gifts of thanks which the light beings have never acknowledged.
In 3277 the Verandi Empire responded to the destruction of several of its merchant ships by sending an Imperial Fleet flotilla into the Angel Sector with the express purpose of combating the light beings. Ignoring warning that the mission was doomed to failure by the surrounding nations, the Verandi fleet managed to penetrate past the border and into the next star system that had previously been unexplored. It is the farthest any known species has penetrated into the sector. The flotilla was forced to retreat, taking 75% casualties and inflicting no damage on the enemy. Again, records of the light being were obtained, only this time they appeared as unnaturally tall humanoids, hairless and eyeless and capable of great feats of strength that utterly crippled the Verandi warships. Marines inside the ships report that they were unable to even see the enemy as they wrecked the vessels, let alone combat them. These "angels" as the Verandi termed them, disappeared without a trace once the ships left their space. A second invasion, mounted in 3278, and third in 3281 met the exact same fates, taking 70% casualties and making the Angel Sector Campaigns the most lopsided defeats in Verandi history. Verandi declared the Angel Sector off-limits to its citizens soon after.
International conferences have determined that no one is allowed to enter the Angel Sector without the permission of the governing bodies who ratified the agreements made during these conferences. This was codified in 3532 when the Galactic Nations was given oversight of all research facilities around the Angel Sector and had it declared a Permanent Forbidden Zone.
There are numerous theories regarding the Angel Sector and its inhabitants.
Some Sirian scholars believe that the Angel Sector is host to an alien race that is related to their former masters, but there is much debate as to the nature of the relationship, not to mention why the Sirians never encountered the Angel Sector aliens if their empire had contact with them. As a result, though the concept has some currency it's not currently an accepted part of mainstream theory.
Officially, the Verandi Empire treats the Angel Sector as a hostile environment, but has stopped short of actually declaring the angels to be enemies. Among the common people it is often said that the angels are in fact literal angels and that they are protecting the gateway to Heaven. Others maintain that there is nothing supernatural about the angels, but that they are an advanced isolationist species who employ cyber warfare and gravity manipulation technology to keep others out of their territory.
Representatives from the Ashkathi Union have stated that they believe the Angels to be spirits stuck in the mortal plane, unable to cross to the other side and angry because of it. Unmanned drone ships were parked outside the Angel Sector, beaming Ashkathi songs into the Sector in order to help the Angels "become one within the Songstream". So far, no response has been detected.