The Einstein's Revenge Cluster is an open star cluster in Sagittarius, 6201 light-years from Sol. This cluster contains six relatively quiescent neutron stars, all of which have a similar age of around 144 million years.
The cluster itself cannot be easily observed from the Inner Sphere because it is hidden by dust clouds, so was largely unstudied until the Age of Expansion. Closer observations in the 8000s AT reveal anomalous emissions from the neutron stars, prompting an exploration mission that arrived in 9800.
Each of the neutron stars has been found to contain an exotic biosphere, and KJEI-54-458945 also contains the Hildermar's Knots, an intelligent species with a unique culture and psychological type.
Sagittarius Outer Volumes - Text by M. Alan Kazlev Extensive region of space coreward of the Sagittarius Transcultural Cooperation and MPA space, popular with development and strategic interests because it is seen as the gateway to the Sagittarius Arm.