Planetary Size

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Planetary Size: Worlds are classified according to their physical size.

Please see the following AAB Library Data articles for more information:

Description (Specifications)[edit]

Planetary density and size are two primary factors when determining a planet's gravity.

Planetary Size Data[edit]

The following table outlines the UWP codes for the size of a body:

Planetary Size
Code Description Diameter (Km) Expected
R Asteroidlet / Planetary Ring

(...around a world)

Multiple < 1 Microgravity
(0.01 G or less)
Planetary Ring (Tiny World)
D Debris 1+ < 200 Microgravity
(0.01 G or less)
Debris Field / (Tiny World)
0 Asteroid / Planetary Belt

(...around a star)

Multiple < 200 Microgravity
(0.01 G or less)
Planetoid Belt (Tiny World)
S Very Small 200-799 Very Low Gravity
(400 km, 0.02g - 0.03g)
Very Small World
1 Small 800-2399 Very Low Gravity
(1,600 km, 0.05g - 0.09g)
Small World
2 Small (e.g. Luna) 2,400-3,999 Low Gravity
(3,200 km, 0.10g - 0.17g)
Small World
3 Small (e.g. Mercury) 4,000-5,599 Low Gravity
(4,800 km, 0.24g - 0.34g)
Small World
4 Medium (e.g. Mars) 5,600-7,199 Low Gravity
(6,400 km, 0.32g - 0.46g)
Meso World
5 Medium 7,200-8,799 Standard Gravity
(8,000 km, 0.40g - 0.57g)
Meso World
6 Medium 8,800-10,399 Standard Gravity
(9,600 km, 0.60g - 0.81g)
Meso World
7 Large 10,400-11,999 Standard Gravity
(11,200 km, 0.70g - 0.94g)
Macro World
8 Large (e.g. Venus / Terra) 12,000-13,599 Standard Gravity
(12,800 km, 0.80g - 1.08g)
Macro World
9 Large 13,600-15,199 Standard Gravity
(14,400 km, 1.03g - 1.33g)
Macro World
A (10) Huge 15,200-16,799 Standard Gravity
(16,000 km, 1.14g - 1.48g)
Big World
B (11) Huge 16,800 - 18,399 High Gravity
(17,600 km, 1.49g - 1.89g)
Big World
C (12) Huge 18,400+ Very High Gravity
(17,600 km, 1.9g - 2.0g)
Big World
SGG Small Gas Giant (no futher codes) 40,000-120,000 Macrogravity
(2.01 G or higher)
Gas Giant
LGG Large Gas Giant (no further codes) 120,000-240,000+ Macrogravity
(2.01 G or higher)
Gas Giant
  • NOTE-1: Please note that the size code D ( Debris ) is non-standard. It is included to cover such cases as Comet Mid-Rift (Deneb 3234), which are less than 200Km, but not part of an asteroid belt, yet important enough to have mention.
  • NOTE-2: Please note that gravity values are estimations based on a standard planetary density. Planets with less or more dense cores may have very different values from the suggested average.

History & Background (Dossier)[edit]

When the UWP was created, any number of planetological figures were considered for inclusion. Initial discussion led to 16 and 32-factor descriptive chains, but theose were too many, especially for a Universal Code. Eventually the UWP was pared down to just eight factors. Of those eight factors, one of the most disputed was Planetary Size.

Size included many, many factors including:

  • Gravity
  • Physical measurement parameters
  • Planetary density
  • Tectonics
  • Vulcanism
  • etc.

A very unhappy compromise was eventually settled upon even though it as serious shortcomings.

Basic UWP Stats[edit]

Physical Stats (...the entire sequence):

SAH Sequence (planetology):

PGL Sequence (socioeconomics):

TL (technology):

Image Repository[edit]

No information yet available.

References & Contributors (Sources)[edit]

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