The Solerian Rift is a tremendous cloud of volatile gas several parsecs across; since its boundaries are constantly shifting, an exact size reference is impossible to determine. Similar in composition to nebulae, it is considerably larger than is average for this type of phenomenon. In addition, the gases that make up the Rift are extremely unstable, given to generating ionic charges as well as emitting electromagnetic interference and sensor-diffusing particles at a great rate.
The Rift is also the birthplace of thousands of infant stars, which increases the ambient radiation of the cloud immensely. This combination of radiation, and the buildup of ionic charges in the particles of the Rift contribute in the formation of titanic electromagnetic storms that frequently sweep through the Rift. These "lightstorms" - often hundreds of light years in diameter - are capable of swallowing an entire fleet while and leaving behind only miniscule amounts of debris. Obviously, the Rift is an exceedingly dangerous region to travel.
It’s furthest ‘southern’ edge borders the Sagittarius Reach.
Conventional wisdom states that the Rift is impassible, but this is not strictly true. A species of mystics called the Tiins-la Sanhedrim frequently traverses the Rift in response to mysterious "calls from beyond the Rift" that the Tiins-la claim to hear. While the Tiins-la are an inscrutable, eccentric group, they nonetheless travel the Rift with relative ease.
There are currents and eddies - referred to as "corridors" - that twist through the Rift, and the Tiins-la are highly adept at locating these currents, allowing ships to pass through the Rift without being destroyed. Rift currents often change position, sometimes dozens of times in a single day. There is presumably some pattern to the shifting of these currents, though none has yet been discovered except by the Tiins-la monks.
While it is possible to travel through a corridor, it is not advisable: shield strength is depleted by particle buildup, sensors are reduced to minimal resolution, and weapons systems are also rendered nearly non-functional. In addition, going to warp must be carefully monitored; jumps often last no more than a few seconds in the Rift. This is due to the lightstorms, and forming stars or one of the thousands of planets inside the Rift. The corridors have also been known to shift position while a ship is traveling in them, forcing the vessel into the dense, impassible regions of the Rift.
Several of these safe areas are located around planets formed in the Rift, allowing life forms to survive on many of the worlds in the anomaly. Unfortunately, the effects of the Rift have touched these places as well; the life forms that inhabit Rift worlds are often primitive, unstable and generally on the verge of extinction. The radioactive and electromagnetic instability of the Rift has only allowed these life forms to exist, not to thrive.
The "safe corridors" in the Rift are not quite as harmless as the term implies. They are not devoid of the radiation and charged particles that make up the Rift; they simply don't have as high a concentration of them as other areas. All weapon ranges are halved, shields only provide minimal protection, and sensors and communications equipment do not perform well. In addition, the presence of a starship acts as a sort of "lightning rod" to the energy discharges of the Rift. When moving at sub-light speeds, vessels are pounded with energy bolts and swirling radiation vortexes. These discharges perpetually hammer a starship, but are typically of low strength, though they can be more dangerous.
Other Effects of the Rift
The Solerian Rift has long been a source of tales about weird phenomenon, spectral apparitions, lost colonies, derelict alien ships and other pieces of folklore common among the superstitious peoples of the galaxy. While many of these stories are obvious fabrications, a good number of them contain a nugget of truth as well.
Individuals often complain about severe headaches, nausea, and hallucinations during travel through (and even occasionally near) the Rift, particularly those with telepathic tendencies. Often these hallucinations are eerie, spectral images of small, hairless, robed bipeds with large eyes, slit noses and tiny mouths set in large rounded skulls. Other "common" visions are of an arachnid creature that is constantly grasping at everything around it. At its best, the Rift tends to make those who pass through it nervous, irritable and uneasy. Odd noises echo through the ships passing through the Rift, noises that have no visible source. Unexplained system malfunctions strike non-essential ships' systems. Navigational equipment often displays conflicting data. In short, the atmosphere of the Rift is sinister and disorienting.
Legends abound about how the Rift was formed; some claim it is merely a natural phenomenon and that its unusual effects are simply the result of the radiation and electromagnetic interference, others claim that the region was once the site of a catastrophe that was so terrible that it physically warped surrounding space. In truth, no one knows for certain how the Rift was formed.