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Terraforming Questions

Terraforming in Traveller

For those interested in long-term changes to planets, the following is a system you can apply for terraforming them that uses the existing UWP characteristics.

Start with the base values of the world. What you will be doing is altering these up or down. Each value may be altered by one (1) point at a time using the tables below.

The three characteristics that can normally be altered are atmosphere, hydrographics, and a broad category explained below called other.

There are some rules about the order values have to be altered in some cases. These are:

  • The world size must be 1 or greater to have an atmosphere. The atmosphere cannot be greater than planet size by more than 5.
  • The world must be size 2 or greater to have hydrographics. The atmosphere must be 3 or more.
  • Size cannot be altered with extant game level technologies. TL 16 and up can attempt to alter a planet’s size.
Only one characteristic of the planet may be changed at a time. At TL 16 or above two characteristics may be changed at a time. In all cases, the original UWP profile is used as the baseline for all changes.

The time period per attempt (roll) is 10 standard years.

The table below gives the base values for success. Roll 2D6. The resulting value, with modifiers has to exceed the value on this table for the terraforming attempt to be successful.

Change from base _______value Roll needed

  • 1_________________________6
  • 2_________________________9
  • 3________________________12
  • 4________________________15
  • 5________________________18
  • 6________________________21
  • 7________________________27
  • 8________________________35
Note, changes of more than 3 to a world’s UWP are not possible without modifiers. The change can be to increase or decrease the base value. The base value is always used to determine the difference.

Technology effects:

Tech _________Level Modifier

0-3____________ -12

4-7 _____________-8

8-9 _____________-4

A-B _____________-2

C-E ____________+1

F _______________+2

G ______________+4

H ______________+6

I _______________+9

Population effects:

Population_______ Modifier

6-7_______________ +1

8 _________________+2

9 _________________+3

A _________________+4

Economic impact on the economy of terraforming.

A planet can deliberately choose to put more economic effort into terraforming at the expense of the economy in general. The baseline assumes that no major impact is made to other portions of the economy when doing terraforming.

If a planet chooses “some impact” a +2 modifier is given. The population must be greater than 5 to choose this. This results in the planet’s economic situation becoming the equivalent of an amber zone and should be treated that way for purposes of trade. This reflects the local economy putting more resources into terraforming.

If a planet chooses “Major impact” a +4 modifier is given. The population must be greater than 5 and the government cannot be types 0,2,4, or 7. The world is now treated as equivalent to a red zone for trade. That is, the maximum amount of local economic effort is being put into terraforming and there’s nothing left to trade on.

Outside influence:

It is possible that other worlds or interstellar governments could be involved in terraforming a planet. When this is the case, the following guidelines are used:

  • The TL of the terraforming is the TL of the world or government doing it, rather than that of the world being terraformed.
  • The economic impact modifiers can be applied to this operation without penalty to the planet being terraformed economy. Note, if the outside influence is a single other world, the penalties apply to that world instead. An interstellar government suffers no penalty so long as the number of worlds being given economic help are less than 2% of the total worlds controlled. When this is exceeded, the impact is as noted in the rules.
  • The population modifiers are reduced by two levels to reflect that more of the population on the terraformed world are involved in this operation. That is, a population of 4 on a world equals a population 6 when outside assistance is being applied.
Other changes that can be made (optional):

These changes can only be made by TL 9 worlds and above. Anything below that, and they cannot be done.

Terraforming can also change the following characteristics of the planet:

Magnetosphere: That is, the magnetic field of the planet. For each attempted 10% change this counts as 1 one change from the base value.

Sunlight: To increase or decrease the amount of sunlight on a planet by 10% represents a change of 1 from the base value.

Gravity: To change the gravity of the planet by 10% using artificial means represents a change of 1 from the base value.

Changing the orbit of the world (eccentricity and/or distance) by 5% represents a change of 1 from the base value. In addition, the size of the world is considered the difficulty level. That is, if the world is size 4 the difficulty base is 4 needing a base roll of 15.

Adding or removing a satellite: The base difficulty is the satellite size S, 0, and 1 use 1. This is really little different than moving a large asteroid to be used as a ship, only it is assumed to take more time as the movement rate is lower. For satellites larger than 0, there must be an asteroid belt present. For satellites size 2 or greater, there has to be an existing one in the system for use.

Shell worlds. These are possible at higher tech levels. There are two versions: The first is hollowing out the existing world and building a biosphere within the shell. The second type is encasing an existing planet with a mini-Dyson sphere. The minimum tech level necessary is 16 and the difficulty of doing either is considered a shift of 6.

Special cases for atmospheres:

Because the tables for atmospheres above 9 are specialized, the following special case rules are necessary:

An A atmosphere changes to a 9, a difference of 1.

B and C atmospheres change to an A, a difference of 1

D atmospheres change to a 9, a difference of 1. They are treated as an atmosphere type A for the starting point for further modification.

E and F atmospheres change to a 5, a difference of 1. Once converted to a 5 their base value for further modification is considered a 4.

Economic impact of terraforming:

Where the economic impact of terraforming is needed, the following table gives a rough set of percentages as guidelines for use. These percentages represent the portion of the GDP of the world being applied to terraforming. This portion would be applied to reducing trade and exports.

No serious economic impact = 3 to 7%
Some economic impact = 15 to 20%
Major economic impact = 30%+

Where a world is receiving outside assistance the “No serious economic impact” values apply regardless of the amount of extra economic input being put into terraforming.

Terraforming expertise

In the case of civilizations that practice terraforming on a wide scale, or as a business, a + 1 to +4 can be added to rolls for their level of expertise.

Some expertise = +1

Ongoing, regular expertise = +2

Experts in terraforming = +4

It pays to hire experts if you can afford them.