The Cleaved Helm

Naval Intelligence World Profile: Entrope

"Considerable tension still exists . . . concerning three worlds . . . claimed by the Sword Worlds. . . . The [Darrian] Confederation disputes the claim, citing the fact that the worlds were originally settled by Darrians."
— Roger Moore, "Contact: The Darrians,"
Journal of the Travellers' Aid Society #14

Entrope^[*]

World	Location	UWP	Ba	Trade	Remarks	Al	PBG	Stars
Entrope	05S03C	C336777-9	-	-	-	In	210	G6V M1D

Entrope is located in the Entropic spur, along the Main core-spinward of the Horseshoe. It has a substantial population composed primarily of the descendants of ancient Darrian settlers and has received substantial development assistance in recent decades from the Darrian worlds. It has established a small agricultural settlement on neighbouring Wynstan and a small mining settlement on neighbouring Ansehelm. In cooperation with the Darrians another small mining settlement has been established on neighbouring Irka.

Entrope world map^[ᚠ]

The name of the world Entrope is derived from the Darrian word for hypoxia or oxygen deficiency, the physiological condition resulting from trying to breath the planet's atmosphere unaided.

Entrope and surrounding worlds
(Modified from The Traveller Map)

Entrope is a barely-hospitable, mineral-resource planet orbiting Bynoth, a yellow dwarf (main-sequence) star with a mass of [- redacted -] and a stellar luminosity of [- redacted -], in the life zone (fourth orbit) at a distance of 25 light-minutes. It has an orbital period of 1800 standard days, with almost no orbital eccentricity. A red degenerate-dwarf companion, Doon, is in the fourteenth orbit.

Entrope is a small planet with a diameter of 4800 kilometers and a molten core. The density is 1.0 standard, the mass is 0.05 standard and the surface gravity is 0.4 g (with an escape velocity of 4 kilometers per second). The rotation period is 13.4 standard hours and the axial tilt is 16 degrees. The atmosphere is a very thin oxygen-nitrogen mix, requiring a respirator, with a surface pressure of 0.23 atmospheres. Mostly frozen surface water covers 61% of the planet. The base temperature is -57 °C, with a summer high of -47 °C at the equator and a winter low of -73 °C at the poles. Entrope has very primitive flora and fauna on its land (and frozen water) surface but advanced flora and fauna in its oceans. It as three major continents and three minor continents separated by two major oceans. There is little vulcanism with no notable volcanoes.

The Entrope system consists of the central star, Bynoth (derived from Darrian word for "haze"), four inner, rocky planets (Entrope is in the third orbit), the planetoid belt, Doon's Moat, in the fifth orbit, and the dwarf star Doon (derived from Darrian word for "spark") in the seventh orbit (the sixth orbit is vacant). There are no gas giants and no planets beyond the star Doon, though Doon does have two, small, planet-sized moons.

Detailed World Data (GS, p. i; WBH, p. i) Under construction

UWP: C336777-9 (S03, p. 6)

Location: 05S03C (S03, p. 6)

Date: 11 Nóvember 44 D.E.

Size-related Details

Diameter (3): small (4800 km) (MT2, p. 22)	Density: [‑‑ Redacted ‑‑]	Mass: [‑‑ Redacted ‑‑]
Surface gravity: 0.4g	Primary (star) mass: [‑‑ Redacted ‑‑]	Primary (star) radii: [‑‑ Redacted ‑‑]
Primary (star) 100-diameter limit: [‑‑ Redacted ‑‑]	Orbit number: 3 (1.0 AU) (B06, p. 46)	Orbital period: [‑‑ Redacted ‑‑]
Rotation period: [‑‑ Redacted ‑‑]	Axial tilt: [‑‑ Redacted ‑‑]	Orbital eccentricity: [‑‑ Redacted ‑‑]
Seismic stress: [‑‑ Redacted ‑‑]	Orbit number (if satellite): [‑‑ Redacted ‑‑]	Orbit period (if satellite): [‑‑ Redacted ‑‑]
Satellite: [‑‑ Redacted ‑‑]	Satellite orbit: [‑‑ Redacted ‑‑]	Size - notes: [‑‑ Redacted ‑‑]

Atmosphere-related Details

Atmosphere (3): Vacuum (very thin) (MT2, pp. 22-23)	Composition: oxygen-nitrogen mix (GT01, p. 45)	Surface pressure: [‑‑ Redacted ‑‑]
Stellar luminosity: [‑‑ Redacted ‑‑]	Orbit factor: [‑‑ Redacted ‑‑]	Energy absorption: [‑‑ Redacted ‑‑]
Greenhouse effect: [‑‑ Redacted ‑‑]	Base temperature: [‑‑ Redacted ‑‑]	Eccentricity modifier: [‑‑ Redacted ‑‑]
Axial tilt effects: [‑‑ Redacted ‑‑]	Daytime effect: [‑‑ Redacted ‑‑]	Nighttime effect: [‑‑ Redacted ‑‑]
Native life: advanced fauna	Atmospheric terraforming: none	Greenhouse terraforming: none
Albedo terraforming: none	Climate: frozen (GT01, p. 45)	Atmosphere - notes: [‑‑ Redacted ‑‑]

Temperature-related Details (WBH, p. 68)

Hex Row

Base Temp

Lat Mod (WBH, p. 66)

Row Base

Summ Max

Tilt Fact (WBH, p. 66)

Summ incr

Day Max

Ecc incr

Row High

Wint Min

Wint decr

Nite Min

Ecc decr

Row Low

Hydrosphere-related Details

Hydrosphere (6): wet (61%) (S03, p. 6; GT01, p. 45; MT2, pp. 22-23)	Composition: water ice (GT011, p. 45)	Tectonic plates: [‑‑ Redacted ‑‑]
Hydrosphere terraforming: none (WBH, p. 66)	Terrain terraforming: none (WBH, p. 66)	Major oceans: [‑‑ Redacted ‑‑]
Minor oceans: [‑‑ Redacted ‑‑]	Small seas: [‑‑ Redacted ‑‑]	Scattered lakes: [‑‑ Redacted ‑‑]
Notable volcanoes: [‑‑ Redacted ‑‑]	Trade classification: none (MT2, pp. 21, 25, 48)	Natural resource exports: [‑‑ Redacted ‑‑]
Processed resource exports: [‑‑ Redacted ‑‑]	Manufactured good exports: [‑‑ Redacted ‑‑]	Information exports: [‑‑ Redacted ‑‑]
Weather control: none (WBH, p. 70)	Hydrosphere - notes: [‑‑ Redacted ‑‑]	Hydrosphere - notes: [‑‑ Redacted ‑‑]

Population-related Details

Population (7): moderate (20,000,000) (MT2, pp. 22, 25)	Very large cities: [‑‑ Redacted ‑‑]	Large cities: [‑‑ Redacted ‑‑]
Orbital cities: none (WBH, p. 74)	Progressiveness: [‑‑ Redacted ‑‑]	Aggressiveness: [‑‑ Redacted ‑‑]
Extensiveness: [‑‑ Redacted ‑‑]	Local customs: [‑‑ Redacted ‑‑]	Population - notes: [‑‑ Redacted ‑‑]

Government-related Details

Government (7): regional rivalry (MT2, pp. 22, 24)	Division of authority: [‑‑ Redacted ‑‑]	Primary authority organization: [‑‑ Redacted ‑‑]
Secondary authority organization: [‑‑ Redacted ‑‑]	Tertiary authority organization: [‑‑ Redacted ‑‑]	Allegiance (In): Independent
Religious profile: [‑‑ Redacted ‑‑]	Religious deity view: [‑‑ Redacted ‑‑]	Religious spiritual aim: [‑‑ Redacted ‑‑]
Religious devotion required: [‑‑ Redacted ‑‑]	Religious organization: [‑‑ Redacted ‑‑]	Religious liturgical formality: [‑‑ Redacted ‑‑]
Religious missionary fervor: [‑‑ Redacted ‑‑]	Religious adherents: [‑‑ Redacted ‑‑]	Government - notes: [‑‑ Redacted ‑‑]

Law-related Details

Law (7): moderate (MT2, pp. 22, 24)	Legal profile: [‑‑ Redacted ‑‑]	Uniformity: [‑‑ Redacted ‑‑]
Weapons: [‑‑ Redacted ‑‑]	Trade: [‑‑ Redacted ‑‑]	Criminal: [‑‑ Redacted ‑‑]
Civil: [‑‑ Redacted ‑‑]	Personal freedom: [‑‑ Redacted ‑‑]	Law - notes: [‑‑ Redacted ‑‑]

Technology-related Details

Starport (C): routine quality installation (MT2, pp. 17, 23)	Technology level (9): pre-stellar ( MT2, pp. 23-24)	Bases: none (MT2, pp. 20, 24, 29)
High common: [‑‑ Redacted ‑‑]	Low common: [‑‑ Redacted ‑‑]	Energy achievement: [‑‑ Redacted ‑‑]
Computers / robotics achievement: [‑‑ Redacted ‑‑]	Communications achievement: [‑‑ Redacted ‑‑]	Medical achievement: [‑‑ Redacted ‑‑]
Environmental achievement: [‑‑ Redacted ‑‑]	Land transport achievement: [‑‑ Redacted ‑‑]	Water transport achievement: [‑‑ Redacted ‑‑]
Air transport achievement: [‑‑ Redacted ‑‑]	Space transport achievement: [‑‑ Redacted ‑‑]	Personal weapons achievement: [‑‑ Redacted ‑‑]
Heavy weapons achievement: [‑‑ Redacted ‑‑]	Novelty: [‑‑ Redacted ‑‑]	Technology profile: [‑‑ Redacted ‑‑]

Detailed World Data notes:
[‑‑ Redacted ‑‑]

Primary Star System Data (B06, pp. 51-53; MT2, pp. 26-29) Under construction

Primary: Bynoth	Spectral class (G6): red (M3, p. 23; B06, pp. 22-23, 28, 41-43, 45; MT2, pp. 18, 26)	Size (V): dwarf (main sequence) (M3, p. 23; B06, pp. 22-23, 28, 41-43, 45; MT2, pp. 18, 26)
Companion orbit number: [‑‑ Redacted ‑‑]	Maximum orbit number: [‑‑ Redacted ‑‑]	Available orbits: [‑‑ Redacted ‑‑]
Habitable orbit: 3 (B06, pp. 29, 30-31, 34, 35, 43, 46; MT2, pp. 18-19, 27, 28; WBH, p. 59)	Empty orbits: [‑‑ Redacted ‑‑]	Captured planets: [‑‑ Redacted ‑‑]
Gas giants (0): none (M3, p. 23)	Gas giant orbit number: n/a	Gas giant size: n/a
Planetoid belts (1): Doon's Moat (M3, p. 23)	Planetoid belt orbit number: 5 (B06, p. 35; MT2, pp. 19, 28)	Predominate planetoid diameter: [‑‑ Redacted ‑‑]
Planetoid belt zones: [‑‑ Redacted ‑‑]	Planetoid belt width: [‑‑ Redacted ‑‑]	Primary - notes: [‑‑ Redacted ‑‑]

Companion Star System Data (B06, p. 51-53; MT2, pp. 26-29) Under construction

Companion: Doon (B06, pp. 22-23, 28; MT2, pp. 18, 26)	Spectral class (M1): red (M3, p. 23; B06, pp. 22-23, 28, 41-43, 45; MT2, pp. 18, 26)	Size (D): dwarf (M3, p. 23; B06, pp. 22-23, 28, 41-43, 45; MT2, pp. 18, 26)
Maximum orbit number: [‑‑ Redacted ‑‑]	Available orbits: [‑‑ Redacted ‑‑]	Habitable orbit: none (B06, pp. 29, 30-31, 34, 35, 43, 46; MT2, pp. 18-19, 27, 28; WBH, p. 59)
Empty orbits: none (B06, pp. 23, 28; MT2, p. 28)	Captured planets: [‑‑ Redacted ‑‑]	Gas giants: none (M3, p. 23; B06, pp. 28, 34, 35, 39; MT2, pp. 18, 25, 28; WBH, pp. 53, 60)
Gas giant orbit number: n/a (B06, pp. 34, 35; MT2, pp. 18, 28)	Gas giant size: n/a (B06, pp. 28, 39, 48; WBH, pp. 53, 60)	Planetoid belts: none (M3, p. 23; B06, pp. 28, 34-35, 39; MT2, pp. 18-19, 25, 28; WBH, pp. 52-53, 61)
Planetoid belt orbit number: n/a (B06, p. 35; MT2, pp. 19, 28)	Predominate planetoid diameter: n/a (WBH, pp. 52-53, 61)	Planetoid belt zones: n/a (WBH, pp. 52-53, 61)
Planetoid belt width: n/a (WBH, pp. 52-53, 61)	Companion - notes: [‑‑ Redacted ‑‑]	Companion - notes: [‑‑ Redacted ‑‑]

Primary System World and Satellite Data (B06, pp. 51-53; MT2, pp. 28-29) Under construction

Orbit

Radii

Name (UWP)

Remarks

Companion System World and Satellite Data (B06, pp. 51-53; MT2, pp. 26-29) Under construction

Orbit

Radii

Name (UWP)

Remarks

Entrope History

SW	OEU	Historical event
-	c3181	Darrian explorers reach Entrope. (AM08, p. 9; GT31, p. 6; GT23, p. 34)
-	c3389	Darrians establish scientific outpost on Entrope. (AM08, p. 9-12; GT31, pp. 6-7; GT23, pp. 34-36)
-	3596	Though beyond the range of physical disruption caused by the Maghiz, outpost on Entrope loses contact with Darrians, becomes self-sustaining settlement. (AM08, pp. 9-12; GT31, pp. 6-7; GT23, pp. 34-36)
c2 F.E.	c4123	Sword Worlders from Gram discover Entrope but make no contact with inhabitants (instead begin plans to establish colony on Hrunting).
c135 F.E.	c4257	After encountering Sword Worlders at Tizon, Darrian explorers from Mire reach Entrope.
c212 F.E.	c4333	First Gram-Sacnoth War begins.
?	?	With assistance from Darrians, Entrope establishes agricultural colony on Wynstan and mining colony on Ansehelm. Entrope and Darrians establish joint mining colony on Irka.

^[*] Sacnoth Dominate Naval Intelligence (SDNI) World Profiles are a reference resource produced by SDNI with almanac-style information about the worlds surrounding Sword Worlds space. It provides a brief summary of the planetography, sociography and political-economy of the inhabited worlds in the Sword Worlds surrounds. Some information is redacted from publicly available editions for security purposes. (Note: the information presented here for Entrope relies extensively upon Daryen's Entrope Landgrab. Daryen — Mike West — also makes an interesting alternate choice for the New Era: switching the physical UWP data for Entrope and Winston. But West's original Landrab History — a later version of a 2002 draft posted to the Traveller Mailing List — offers a reasonable explanation for the large population on barely-hospitable Entrope.)

Entrope Canon and Apocrypha
(AAB entry / Webb's Canon)

Excerpts of Dominate-era information about Entrope from various published Traveller^® sources (in order of original publication).

— 1979 —

• Supplement 3: The Spinward Marches (S03): "Querion Subsector," pp. 6-7 (Milieu 1105 world and system data for Entrope).

— 1982 —

• Introductory Adventure: The Imperial Fringe (A00): "Querion Subsector," p. 27 (Milieu 1105 world data for Joyeuse).

— 1985 —

• The Spinward Marches Campaign: Adventures in a War Ravaged Sector (M3): "Fifth Frontier War: The Darrian Campaign," p. 11 (Joyeuse Fleet movement and engagements in the War); "The Spinward Marches: Querion Subsector (E)," p. 18 (competing Darrian and Sword Worlds claims to Entrope); "Spinward Marches Data," p. 23 (Milieu 1105 world and system data for Entrope).

— 1987 —

• Alien Module 8: Darrians: The Secret of the Star Trigger (AM08): "History of the Darrian People: The Darrian Explosion / The Golden Age of Darrian / Darrian's Ultimate Disaster," pp. 9-10 (ancient Darrian exploration and settlement in region around Entrope); "The Effects of the Maghiz (-925 to -907)," p. 11 (ancient Darrian outpost on Entrope avoids physical disruption of the Maghiz); "History of the Darrian People: Night Time," p. 12 (Darrian settlements in Entropic Worlds region lose contact with Darrian worlds); "Darrian Colonies," pp. 24-25 (ancient Darrian settlements in Entropic Worlds region struggle).

• Imperial Encyclopedia (MT3): "Spinward Marches Data," p. 95 (Rebellion Era world and system data for Entrope).

— 1992 —

• MegaTraveller Journal #3 (MTJ3): "Domain of Deneb Sector Data," p. 48 (Rebellion Era world and system data for Entrope).

— 1995 —

• Regency Manual 1: Keepers of the Flame, The Regency Sourebook (RM1): "Spinward Marches Subsector E: Querion," p. 40 (Rebellion Era and New Era world and system data for Entrope).

— 1998 —

• Behind the Claw: The Spinward Marches Sourcebook (GT01): "0720 Entrope (Darrian)" p. 45 (Milieu 1120 world data, brief description for Entrope).

— 2000 —

• Journal of the Travellers' Aid Society (online), August 29, 2000 (GJ0829): "The Sword Worlders" (discussion of conflicting canon on Darrian and Sword Worlds historical control of Entrope).

— 2003 —

• Humaniti: The Infinite Variety of Mankind in Space, (GT23): "The Darrian Explosion," pp. 34-35 (ancient Darrian exploration and settlement in region around Entrope); "Night Time," p. 36 (Darrian settlements in Entropic Worlds region lose contact with Darrian worlds); "Rebuilding the Darrian Community: The Sword Worlds," pp. 36-37 (early Sword Worlder detection of Darrian settlements in region, reluctance to engage Darrians).

— 2004 —

• Sword Worlds: The Day After Ragnarok (GT31): "History: The Darrians," pp. 6-7 (ancient Darrian exploration and settlement in region around Entrope, ancient outpost on Entrope); "History: The Second Dominate," pp. 17-19 (Darrian and Sword Worlds conflict over the Entropic Worlds); "Library Data: Thorfinn Burkhardsson Aagard," p. 80 (Milieu 1120 era Sword Worlds claims to Entropic Worlds); "Library Data: Court in Exile," pp. 82 (historical Sword Worlds claims to Entropic Worlds); "Library Data: Entrope and Entropic Worlds," p. 82 (Milieu 1120data for Entrope).

— 2008 —

• The Third Imperium: The Spinward Marches (3I:SM): "Querion Subsector," p. 74 (Milieu 1105 details for Entrope), and "Querion Subsector" (table), p. 76 (Milieu 1105 world and system data for Entrope).

Image credits:
^[ᚠ] Map derived from original map illustration from Daryen's Entrope Landgrab. No endorsement of The Cleaved Helm has been made or is implied.
^[ᚡ] Map modified from The Traveller Map. No endorsement of The Cleaved Helm has been made or is implied.

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