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Note: X and Y are coordinates (light years on XY plane) relative to Terra at (0, 0)

Castor neighbouring systems
Castor neighbouring systems
System information
X:Y Coordinates -40.43 : -16.68[e]

The Castor system is home to at least one habitable world and as at 3145 was located in the Wolf Empire.[1][2]

System Description[edit]

The Castor system is located near the Devil's Rock and Pollux systems.[1][2] Relatively little information is available on the Castor system, but it is known that the system has at least six planets, and that at least one of those planets is inhabited and is an eight-day transit from the system nadir jump point at an acceleration of 1g. It is also known that the sixth planet in the system, Castor VI, has several moons, and that just beyond the orbit of the most distant of those moons is a known pirate point.[3]

System History[edit]

The Castor system was colonised at some point during the First Exodus from Terra[4] and was a member of the Terran Hegemony by the time the Capellan Confederation was founded in the mid-twenty-fourth century.[5]

Amaris Civil War[edit]

The Castor system became the resting place of the SLS Nelson, a Black Lion-class battlecruiser and winner of the Star League Defense Force Martial Olympiad in 2732; the Nelson played an important part in the liberation of Oliver, but took heavy damage in the process. The crew of the Nelson managed to nurse her as far as the SLDF fleet station in the Castor system, only for the SLDF command to declare that the Nelson wasn't considered a viable candidate for repair. As a result of this decision the Nelson was scuttled and abandoned in a long elliptical orbit around Castor.[6]

Clan Invasion Era[edit]

With the assistance of the Word of Blake the Free Worlds League discovered the location of the SLS Nelson in the Castor system and retrieved her, transporting her to the Ionus system to be repaired in secret at the Illium Shipyards before returning her to active service under a new designation, that of the FWLS Xanthos.[6]

Political Affiliation[edit]

Planetary History[edit]

Reunification War[edit]

By the end of the Reunification War Castor was a world within the Tyrfing Province of the Terran Hegemony.[9]

Succession Wars[edit]

In June 3011 two mercenary units in the employ of the LCAF, Snord's Irregulars and the Kell Hounds launched a joint attack on Castor. The mission was to find and destroy a rumored stockpile of old nuclear weapons, and to give the Kell Hounds some combat experience in the process (their first combat mission in fact);[36] Cranston Snord also intended to try and acquire a collection of Fabergé eggs believed to be on Castor, and to have the Irregulars humiliate the Thirtieth Marik Militia. According to subsequent commentary from Captain Jonathan Taylor, Thirteenth Marik Militia, Second battalion, First company, Cranston Snord personally destroyed his Centurion during that joint raid, indicating that at least elements of the Thirteenth Marik Militia were involved in the fighting.[37] The attackers managed to identify and destroy the weapons cache just before the defenders could use the nuclear weapons on the attackers with the intent of framing them for using them. By lucky chance, Cranston Snord, while looking for the Fabergé eggs, apprehended Colonel Nage of the Thirteenth Marik Militia in the open market of Alfagemini City and also ultimately managed to secure nine Fabergé eggs for the Irregulars' museum on Clinton.[20]

Operation GUERRERO[edit]

Castor was invaded in the second wave of Operation GUERRERO by the Third Sirian Lancers. The few planetary militia units on planet were easily defeated.[38]

The Jihad[edit]

On the 23rd of September 3075 Castor was one of three worlds in the Protectorate to be raided simultaneously by unidentified forces. The raiders damaged the defending Protectorate and Militia forces, and were rumoured to actually be drawn from the Word of Blake's own Shadow Divisions.[39][40]

Military Deployment[edit]



  • Fifth Atrean Dragoons[41]






Planetary Locations[edit]

  • Alfagemini City: a city on Castor.[20]


It should be noted that different years have been given for the 3011/3012 raid on Castor conducted by Snord's Irregulars and the Kell Hounds. The history section of the Kell Hounds sourcebook is ambiguous, noting on p. 5 that the raid was planned in 3011 and then narrating how Snord's Irregulars and the Kell Hounds approached Castor from two directions around 7 June, without stating a year. On page 7, however, it is narrated that the Kell Hounds only returned from the mission in the fall of 3012. In the sourcebook's scenario section, the two scenarios referring to the Clinton battle on pp. 30-31 ("Lowering the Boom") and 56- ("Delta Romeo") are both dated 15 June 3012. Similarly, Cpt. Taylor states he fought the Kell Hounds and Snord's Irregulars on Clinton in 3012.[37] When Lowering the Boom was re-published via BattleCorps in 2008 the timestamp was changed to 7 June 3011; whilst this seems to be an oversight based on p. 5 of the Kell Hounds sourcebook, the reprinted BattleCorps scenario is the more recent publication, and the dates in that source have been given primacy in this article.

Nearby Systems[edit]

Systems within 60 light-years (distance in light years)
Closest systems first:
Devil's Rock 4.5 Pollux 9.0 Zosma 11.6 Oliver 13.0
Tyrfing 13.7 Denebola 15.3 New Dallas 17.0 Afleir 17.5
Graham IV 18.0 Zavijava 18.5 Marcus 18.5 Talitha 19.1
Alula Australis 20.1 Callison 22.2 Lipton 24.0 Hechnar 25.4
Chara 25.7 Van Diemen IV 26.1 Connaught 27.4 Wyatt 28.1
Bordon 28.1 Thorin 29.9 Dubhe 30.2 Haddings 30.8
Milton 30.9 Alchiba 33.0 New Earth 34.3 Chertan 34.3
Muphrid 34.4 Liberty 35.2 Wing 35.3 Alioth 35.8
Procyon 35.8 Dieudonné 36.0 Acubens 36.0 Phecda 37.2
Zollikofen 37.8 Hall 38.2 Cor Caroli 38.9 Sirius 38.9
Menkent 39.7 Remulac 39.8 Mizar 39.9 Irian 40.2
Outreach 41.4 Alhena 42.1 Nathan 42.1 Rigil Kentarus 42.2
Summer 42.9 Wasat 43.1 Alphard 43.3 Terra 43.7
Keid 44.0 Miaplacidus 45.9 Killbourn 46.2 Rocky 47.7
New Home 47.8 Brownsville 48.7 Shiloh 49.1 Savannah 49.3
Aquileia 49.3 Pliska 49.5 Yorii 49.8 Mandal 50.5
Blue Sava 50.6 Galatea 52.5 Gacrux 53.6 Bryant 53.7
Catroxx 54.1 Elgin 54.2 Capolla 54.4 Caph 55.7
Alcor 57.0 Altair 57.9 Lyons 58.1 Syrma 58.5
Epsilon Eridani 59.0 Elbing 59.5 Hsien 59.5


  1. 1.0 1.1 1.2 Era Report: 3145, p. 39, "Inner Sphere - 3145"
  2. 2.0 2.1 2.2 Field Manual: 3145, p. VI, "Inner Sphere - 3145"
  3. The Kell Hounds, p. 5
  4. 4.0 4.1 Handbook: House Marik, p. 13, "Free Worlds League after at their founding in [2271]"
  5. 5.0 5.1 Handbook: House Liao, p. 17, "Capellan Confederation Foundation [2366]]"
  6. 6.0 6.1 Field Manual: Free Worlds League, p. 119, "Renovation/Construction"
  7. Handbook: House Liao, p. 25, "Capellan Confederation After Age of War [2571]]"
  8. Handbook: House Marik, p. 24, "Free Worlds League after Age of War [2571] Map"
  9. 9.0 9.1 Historical: Reunification War, p. 159, "Inner Sphere - 2596"
  10. Era Report: 2750, p. 37, "Inner Sphere - 2750"
  11. Historical: Liberation of Terra Volume 1, p. 11, "Inner Sphere - 2765"
  12. Historical: Liberation of Terra Volume 1, p. 104, "Rim Worlds Republic - [2767] Map"
  13. 13.0 13.1 Historical: Liberation of Terra Volume 1, p. 138, "Operation LIBERATION Wave 1 [July 2772 - December 2774]"
  14. 14.0 14.1 Historical: Liberation of Terra Volume 2, p. 118, "Digesting The Hegemony"
  15. First Succession War (Source Book), pp. 24-25, "Inner Sphere - [2786] Map"
  16. Handbook: House Marik, p. 34, "Free Worlds League after First Succesion War [2822] Map"
  17. Historical: Liberation of Terra Volume 2, p. 122-123, "Inner Sphere - 2822"
  18. First Succession War (Source Book), pp. 112-113, "Inner Sphere - [2822] Map"
  19. Handbook: House Marik, p. 38, "Free Worlds League after Second Succesion War [2864] Map"
  20. 20.0 20.1 20.2 The Kell Hounds, pp. 5-6, 31
  21. Handbook: House Marik, p. 42, "Free Worlds League after Third Succesion War [3025] Map"
  22. Handbook: House Marik, p. 51, "Free Worlds League after Fourth Succesion War [3030] Map"
  23. Historical: War of 3039, p. 133, "Inner Sphere - 3040"
  24. Era Report: 3052, p. 10, "Inner Sphere [3050] Map"
  25. Era Report: 3052, p. 24, "Inner Sphere [3052] Map"
  26. Era Report: 3062, p. 10, "Inner Sphere [3057] Map"
  27. Handbook: House Marik, p. 54, "Free Worlds League after Operation Guerrero [3058] Map"
  28. Era Report: 3062, p. 28, "Inner Sphere [3063] Map"
  29. Jihad: Final Reckoning, p. 43, "Inner Sphere Map - [October 3067]"
  30. Jihad Secrets: The Blake Documents, p. 64, "Inner Sphere [3075] Map"
  31. Field Report: FWLM, p. 17, "FWLM Deployment Map [3079]"
  32. Jihad: Final Reckoning, p. 62, "Inner Sphere Map - [March 3081]"
  33. Field Manual: 3085, p. vii, "Inner Sphere Map - [October 3085]"
  34. Map of the Inner Sphere 3130
  35. Era Report: 3145, p. 10, "Inner Sphere - 3135"
  36. 36.0 36.1 The Kell Hounds, p. 5
  37. 37.0 37.1 37.2 Rhonda's Irregulars, p. 38 ("Raid on Bordon" sidebar)
  38. 38.0 38.1 Shattered Sphere, p. 75, "Operation Guerrero, Second Wave"
  39. Jihad Hot Spots: Terra, p. 18, "Timeline of the Jihad"
  40. Jihad: Final Reckoning, p. 54, "The Jihad In Review"
  41. 41.0 41.1 First Succession War (Source Book), p. 138, "First Succession War Deployment Table - FWLM"
  42. ComStar (sourcebook), p. 85, "Com Guards Deployment Table"
  43. Field Report: FWLM, p. 14, "Regimental Status"
  44. Field Manual: 3145, p. 170, "Clan Force Deployments - Wolf Empire"