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The Crown Cluster is an open cluster located in the Outer Paleas Arm of the Florathel Galaxy.


The Crown Cluster is a fairly large and extremely bright open cluster, with roughly 2500 notable stars and is 133 ly in diameter. The Crown Cluster has a notable Luminous Blue Variable at its center known as Narenna. The cluster is fairly unusual in that it has a large number of habitable worlds interspersed between its massive stars, and it seems to be an island of civilization surrounded by an unusually large area with no intelligent life. Its central star, Narenna, contains a vast dyson swarm that is likely the largest dyson swarm in the local universe.

The cluster also contains many intelligent species, which have united to create the Union of Narenna.

Civilization at the Crown Cluster

The Crown Cluster is entirely colonized by the Union of Narenna, which has a habit of creating vast megastructures around the massive stars of the cluster. Two of the largest dyson swarms surround Narenna and Miraban, the latter has been mostly converted into a Nicoll-Dyson Beam during the Forever War.

Strange things

The Crown Cluster contains several anomalous objects, including a large concentration of Aroteon Stars and two Keligan Stars, the highest concentration of them in the galaxy. There are also many ruins of vast megastructures, as if a vast civilization used to control the cluster several million years ago. However, these machines have proven undatable. There are also many strange planets, some of which have bizarre signals eminating from them. The source of these signals are unknown.

Massive stars

The Crown Cluster houses some of the most luminous stars in the Florathel Galaxy, including the LBV Narenna, housed in a tight central cluster. The small cluster is sometimes nicknamed the Jewel Cluster. The Crown Cluster contains 5 LBVs (One being Narenna), 4 O type stars above 100 solar masses, a Porphyrion star, 17 Wolf-Rayet stars, 3 yellow hypergiants and an orange hypergiant, 23 red supergiants, three black holes and dozens of O-type stars above 50 solar masses. Hundreds of late O and B type stars reside in this cluster, and many more smaller, less massive stars. So it comes as a great surprise as to how many habitable worlds are located near this dangerous, radiation-ridden place. Just for context, here are some notable stars listed below:

Some of the notable stars in the Crown Cluster
Name Catalog name (Sira-Renali luminous objects catalog) Spectral Type Luminosity Avg. Temp
Narenna SR 2 B7 0/LBV 2254000 LSol 13500 K
Ugaloni SR 93 B9 0/LBV+X 1212000 LSol 10400 K
Onear SR 116 OẸpe/P8h 1210000 LSol 325000 K
SR 234 WN7h 1329000 LSol 44400 K
Ketlao SR 243 B0Ia0 1615000 LSol 26100 K
SR 253 O2V(f) 930000 LSol 50300 K
O5.5V+O7V 310000 LSol+177000 LSol 40800+38500 K
SR 268 O5III+WN6h 963000+632000 LSol 42100+102000 K
SR 274 WN5(h) 535,500 LSol 60100 K
SR 277 O5Ibp 1083000 LSol 41500 K
SR 282 Ofpe/WN9+WN3/O3 1530000+306000 LSol 31100+98000 K
Honsin SR 286 O3Ia+O5Ia 1226000+791000 LSol 46500+41400 K
Eorn SR 296 WN7h+BV 1428000+9840 LSol 45800+17600 K
SR 299 O2.5If/WN6 784000 LSol 43500 K
SR 300 O1.7V 876000 LSol 50500 K
SR 301 O4.5IIIf 1048000 LSol 45600 K
SR 302 O2V((f)) 821000 LSol 50000 K
SR 305 O4III(f) 1150000 LSol 44100 K
SR 309 O3V 662000 LSol 47800 K
SR 358 A4 Ia0 839000 LSol 8240 K
SR 367 O3V(f) 893000 LSol 45800 K
Isiran SR 400 ON9.7Ia 753000 LSol 30400 K
Salgare SR 420 O3If/WN7+O4III(f) 1607000 LSol+853000 LSol 43000 K+43800 K

Large Nebulae

The Crown Cluster, being home to many massive stars, includes many large nebulae which are being mined for resources. Many of these are included in the below table.

Some of the notable nebulae in the Crown Cluster
Name Star Catalog name (Ponta nebulosities catalog) Type
Crown Nebula Full Cluster Ponta 18 Star-forming region
Crown Jewel Nebula Isiran Ponta 344 Ejecta Nebula
Ruby Nebula Salgare Ponta 147 Ejecta Nebula
Ornamental Nebula Honsin Ponta 221 Ejecta Nebula
Double-Shell Nebula Ketlao Ponta 179 Ejecta Nebula