Tirane: Making it Scientifically Accurate

 Tirane

There are three major problems with Tirane, which is also called Tirene in some early Challenge articles. Essentially, Loren K. Wiseman didn't read the previously established facts about Tirane, and didn't follow the worldbuilding rules. Not following the worldbuilding rules was quite common in the Colonial Atlas, and Tirane was not the worst offender - Kie-Yuma, Nous Voila and King were far worse.

However, post-Colonial Atlas Loren's article was slowly retconned in official books, and, for example, it was confirmed by the time of the Earth/Cybertech SB that neither America nor Australia had a colony on Tirane, but this is ignored by some. However, Tirane is so messed up it has caused controversy as long as I can remember.

Orbit and Temperature

Firstly, it is disputed which orbit Tirane is even in. In the original 1986 boxed set, it is stated that Tirane is the 4th planet in the system (PG, 16), but the CA made it the first of three planets orbiting AC A. Confusion arises in the 2nd edition, when both contradictory facts are presented a few pages apart. Which is it then? It's the fourth planet, because the 2300 Resource places Tirane in an orbit at 1.05 AU, which is beyond the possible scope of the first orbit and consistent with the 4th.

To be clear, system creation rules rolled a d10 for the first orbit, resulting in 0.1 to 0.9 AU or no planets (if a 10 was rolled, it was rerolled the first time and a second 10 ended system generation with no planets). Subsequent orbits were generated by a multiplier generated from another table. The rules were sketchy about whether you rolled once and populated the system, or kept rolling. Scientifically, the former is correct.

Reconstructing putative rolls to get the lowest error gives a roll of 4 (0.3 AU) for the first orbit, and a multiplier of 1.5. Since AC B prevents stable orbits greater than ca. 3.7 AU, there are seven stable orbits, thus:

 

There are not necessarily planets in orbits 5-7, but 1-3 are filled with something, even if only belts. However, the lack of belt mining indicates no belts. Perhaps it is best thought that all the planets beyond Tirane broke up, and the chaotic structure of the system has swept it clean, with significant bombardment per the CA writeup/ 

A distance of 1.05 AU means Tirane gets 138% of the sunlight of Earth, since Alpha Centauri A has a luminosity of 1.5 Sols. This means Tirane is hot. Really hot. The optimal "Earth like" distance for Tirane is around 1.23 AU. At 1.05 AU, Tirane is still in the life zone, but is in the "inner life zone." The average planetary temperature will be 4 degrees C assuming Earth-ish albedo etc., or about 25 degrees C warmer than Earth. This means Tirane is a "polar planet" with an uninhabitable equator, but reasonably habitable poles. The equator is literally a scorched desert, devoid of life. Where the boundaries of habitability are depend very much on the insolation and the axial tilt of the planet.

Sadly, we don't even know the size of Tirane.

Tirane's Size, Density etc.

Assuming the gravity was read off the colony table in the 2nd ed. (as the CA doesn't give a value), Tirane has a 1.01 G surface gravity (but only 0.9 G in the 1st edition. See Nyotekundu SB, page 71). Assuming it was made using the GDW world generation system, and read off the tables, it likely makes a 1.01 G Tirane a 16,000 km diameter, density 0.8 world, which gives it a mass of 1.61 Earths and a MMWR of 5 with a pressure of 0.978 atm.

If 0.9 G surface gravity were used (economically advantagous) then from the tables a 19,000 km diameter, density = 0.6 world fits, but MMWR drops to 4, and so the planet would be a failed core. This could not be colonised.

The two moons given in the CA are "a small ice ball" (Esa) and a distant rocky moonlet. The first problem is that "ice balls" can only exist in the outer system (by the world creation rules). The heat of the star would have caused the moon to loose all volatiles. Instead let's assume it is an icy cored body. Since Esa is defined to be a small moon, it will not produce significant tides, nor vulcanism. This has some interesting effects, but mountains will be rare, and the lack of vulcanism, combined with the low density, will make Tirane relatively mineral poor.

 However, it is notable that Britain and France did exploit mineral production on Tirane, and so there are certainly some lodes. It's just that there will be far fewer mineral deposits on Tirane. However, in the writeup in the CA Tirane has been under heavy bombardment from the asteroids in the system, and the Azanian colony is a mining operation based at one of the Craters (like the British world of Crater). Clearly a lot of metallic asteroids fell on the planet and this probably gives us the raison d'être for the colony. The planet is pockmarked with asteroid craters, and in many of these there will be significant metal resources. These will be mostly in the equitorial desert, creating an interesting society.

The Colonies and History

The Tirane article messed up several colony names, and even identities. It also made every single colony except the French one independent. Later works have retconned them back.

Most notably, the Australian colony of New Canberra was retconned back out of existence in the Earth/Cybertech SB. The history now is that Australia planted a colony in the Japanese claim, and, after negotiation, they gained mineral rights but, as of 2300, New Canberra no longer exists. In all likelyhood, the Australian plantation was absorbed by the Japanese colony. This was, however simply stating both sets of facts - the historical ones from the CA, and the current colony list in the boxed set.

Similarly, the Argentinian colony was confirmed to still exist in the E/CS, and there is no American colony. The British colony is restated to be Wellon, and the ex-German one Garten in the boxed set, but then the names New Albion and Freihaven are later given. The boxed set said (after the CA) that the American colony was "nearly extinct."

The colonial population is nonsensical, since it would require the plantation of hundreds of millions of humans on Tirane > 100 years prior to reach 1.05 billion. The generally recognised fix is to divide populations by 10. This still requires massive emigration on a scale not seen on other worlds.

The "core" status relates to the average resident having the basic amenities of Earth like indoor toilets. In other colonies, the major cities will be something like a city on Earth, and are classified as "core." The core world status of Tirane simply indicates the majority live with flushing toilets etc. See Beanstalk for the development of BCV-4, only a few decades younger and the richest colony planet. It has a mix of high-tech cities (counted as "core"), but outside toilets and no sewers in places (counted as "frontier).

Given what we have determined about the physical nature of Tirane, it is likely the major population centres are in the northern and southern temperate zones (i.e. average temperature from 0 to 20 degrees c). The temperatures are approximately as follows.

We can make Dave Malesevich's map work. We just need to adjust things slightly.

 

Making Dave Malesevich's Map Work

The map of Tirane in Mongoose 2k3 is a modified version of the map drawn by Dave Malesevich, which in turn are modifications of the map drawn by Dan Schirren in 1996. I was one of the people suggesting modifications. Colin further modified it for 2320, stating in December 2004:

The new color map of Tirane is posted to the files section. It has

semi-official status until OK'd by Hunter at QLI. Then it becomes the

real deal for 2320.

It's pretty close to the Tirane project maps, save that it adds

another island near Tirania that is home to Santa Maria, and Enfer is

not empty, but the location of New Albion, the second British colony

on Tirane.

Thus, it has no canon status, and Dave M owns the copyright.

Per LKW's writeup, there are seven continents mentioned in the CA. Incidently, one of my contributions to the DM map was to point out that DS's map had too many continents. There was then an argument about deleting the continent of Enfer (named by me) and it simply got downsized.

So, taking the geography of Dave M.'s map, the approximate temperature zones are:

There is are two large uninhabitable islands, one of which is New Albion. The north of the ESA continent and the north of Amatersau, and the south of Santa Maria (replacing the non-existent Tirania) are pretty uninhabitable, being way into the death zone.

The Colonies of Tirane

The colonial populations are untenable, and the generally agreed fix is to knock off a zero (the same for Nibelungen). In order of initial settlement, the seven colonies of Tirane are: 

Provence Nouveau (French, 23.9 million) is the original Human colony landed on the southern shore of the ESA continent. It covers about 140,000 sq. km of inhabited area in the temperate to near desert zones (i.e. the size of the state of New York) and lays claim to about 220,000 sq. km of death zone land, upto the Tiranian Alpes (excluding Tundukubwa), which are the site of many mining camps.

Garten (French affiliate, ex-German, 19.5 million) is a satellite of the original ESA settlement allotted to Germany. It consists of the trans-Alpine region of the continent but in practice almost the entire population lives in the 50,000 sq. km fertile Limite River delta region. The Limite River provides an excellent artery to service mining encampments to the north. The whole colony, including the mining region, is about the size of Indiana. Due to French support, Garten was able to avoid occupation by Germany and has declared independence.

Tundukubwa (Azanian, 6.8 million) is the third colony on the ESA continent and is essentially a city-state built to service mining operations in a particularly rich asteroidal crater. It claims about 10,000 sq km 

Wellon (British dominion, 21.2 million) was founded separately from the other ESA colonies, with Britain investing in opening up the northern hemisphere by settling in the New Albion Islands. The main population centres are on the northern islands which only have an area of about 30,000 sq. km and the largest of them, Wellon Island (ca. 20,000 sq. km, capital = Knightsbridge), is about the size of Massachusetts. Further south is the island of New Highlands (ca. 10,000 sq. km) which is well into the desert zone, but cooled by sea currents into being merely tropical and is settled by a few million. Further south the islands of New Scotland (40,000 sq. km) and New Albion (130,000 sq. km) host only mining operations. Wellon is now, like Britain's largest colony of Alicia on Beowulf, a self-governing dominion within the British Empire, and the Imperial Parliament only controls external defence (i.e. there is no Wellon space force), trade (retaining control of the primary orbital port) and foreign relations.

Santa Maria (9.8 million Argentines and 1.8 million Mexicans) is one of the larger colonies, as they got "second pick" after ESA. It is based around Santa Maria bay, and in total is about 150,000 sq. km (about the size of California), although only half of this is habitable, with the rest being mines in the death zone.

Provinca do Brasil (Brazilian, 10.2 million) was claimed by Brazil, but not actively settled until the 2210's (see SotFA, 56). It consists of an island of ca. 70,000 sq. km and a few smaller islands in the southern habitable zone (about the size of Missouri). 

Amaterasu (Japanese, 11.9 million) was the final habitable area on Tirane to be claimed, and the Japanese thus settled it in 2184. The mountainous island of Enfer (ca. 80,000 sq. km, with only about 10,000 sq. km of habitable land) was thus settled, and tantalum was struck. Shortly afterwards the Australians tried to claim it citing a paper claim despite no actual colonisation. Thus resulted in the "1.5th interstellar war" which was quickly settled by negotiation. The Australians renounced their claim in return for a share of the tantalum. This tested the limits of the Melbourne Accords, creating the precedent that no-one could attempt to settle a colony in a reasonable claim, and confirming that actual settlement was need to claim territory (which was the whole point of the accords). There remain some descendents of the Australian settlers in Amatersau.

Additionally, America attempted to settle the unclaimed continent of Tirania in the death zone, but the colonists simply could not survive in such conditions, and the attempt was abandoned. 

A couple of small points follow. 

"Grandseasons"

The change in insolation due to Toliman (AC B) is only about 0.25 degrees C. The borders of the zones shift slightly, but there simply isn't enough insolation to have a major effect. The effect of the grandseasons is thus very mild.

Stutterwarp

All the "early stutterwarp lacked range" was retconned away by the Stutterwarp rewrite under Lester W. Smith. Stutterwaps have always had a 7.7 ly range.

Conclusion

This is really where I was going a quarter of a century ago when the Tirane SB list was started. LKW made some major errors both scientifically, and checking basic facts like what orbit Tirane was in, and what the colonies were. This corrects all that. I know it won't be for everyone.

Could you see on Aurore?

Introduction

Aurore is an interesting planet with some odd orbital dynamics etc. It receives most of its' heat from the brown dwarf it orbits, but essentially no visible light. Tithonus looks like a dull, cherry red stretched disk in the sky, but radiates so little visible light that it is practically none.

Visible light comes from Muphred, a yellow subgiant 6.5 AU away. However, that light is weak compared to Earth. The orbital period around Tithonus creates a 61 standard hour day.

Aurore is tidally locked. It's rotation period around it's axis and it's rotation period around Tithonus are the same. However, there is a slight axial tilt (given as 1 degree) and thus Aurore librates. It sort of wobbles, and I will ignore some minor effects of this.

To compare, on Earth: 

• Strong direct sunlight at equator: 100,000 lux
• Overcast day: 400 lux
• Moonlit night: 1 lux
• Moonless night 0.002 lux

There are three sources of light on Aurore. 

1. Direct Illumination from Tithonus 

Tithonus gives an insolation of 78% of Sol (assuming emissivity = 1)*, but it is almost all infrared. For Sol, a little over half the light is in the visible spectrum (52-55%), but for Tithonus only ca. 0.01% of the light is in the visible spectrum, almost all a dull red. Tithonus gives 0.016% of the visible light of Sol. This gives a light level of about 16 lux, assuming no clouds etc. standing at the hot pole of Aurore.

However, neither colony is at the hot pole.

Aurore and Tanstaafl are in the twilight region of the hot face. They'll be getting in the region of 2 mLux of red light. This is about the same as a moonless night.

Novoa Kiev is over the terminator, and cannot see Tithonus. If there is airglow, it might be the same illumination level as an overcast moonless night (< 2 ulux), but without airglow it is pitch black.

However, Human eyes would be using rods at this light level, and rods essentially do not respond to red light. In both settlement regions, Humans would be functionally blind at night. Completely blind. 

2. Direct Illumination from Muphred 

Muphred is the other major light source, being a bright yellow star 5.85 AU (+/- 0.22 AU) away. It averages 19% of Sol's insolation, but ranges from ca. 17.6 to 20.5% depending on the time of the year. Rubis can be ignored as it is so weak.

A little more of Muphred's light is visible as it is a hotter star than Sol. Say 60% is visible (which I didn't calculate). Say Muphred gives 20% of the visible light of Sol in daylight. At midday you'd get about 20 kLux without clouds, or a typical overcast day. With clouds the light would be dim, but cones would still function. It would like being in a dimly lit room.

Around dawn and dusk it would be closer to a moonlit night.

3. Reflected Light off Tithonus from Muphred

The last night source worth considering is reflected light from Muphred off Tithonus. The albedo of a brown dwarf is ca. 0.1, and so about 10% of the light that strikes Tithonus will be reflected back. This is similar to the moon (0.12 at full moon). Tithonus is 74 times the diameter of the moon and thus reflects ca. 5,500 times more light. However, Aurore orbits 2.42 times the distance of the moon. Very roughly, reflected light will be ca. 12.5 greater than Earth's moonlight. It will be yellow-white light.

The upshot is that reflected light will be quite strong during conjunction (when Aurore is between Muphred and Tithonus, which is midnight with repect to Muphred), maybe giving ca. 10 lux of illumination at the hot pole. This would be on the order of twilight on a clear day. However, the colonies aren't at the hot pole. Novoa Kiev would never see this, being on the dark side of the terminator. Aurore and Tanstaafl would get about 1 lux of white light around "midnight," being equivalent to a full moon.

The Auroran Day-Light Cycle

GDW's Aurore has a 61 hour day.** Since the colonies are tide-locked, and on different sides of the terminator, the effects are different. Auroran midday is taken as Aurore being in opposition with respect to Muphred, and midnight as conjunction. The Aurore SB (page 37) gives the normal pattern of an Auroran day, noting that a local hour is 60 minutes and 51 seconds long, and so they work 60 local hours per day.  

In Novoa Kiev it is basically pitch black for 30 h at a stretch. NK is over the terminator and so they don't get much light from Tithonus either. Passive night-vision simply does not work in NK, and active illumination or thermals are needed to operate at night. 

In Aurore and Tithonus, there is still some near infra-red and so Kafers can see perfectly well and PNG's will work. Reflected starlight becomes significant towards midnight, and the night is more like a Terran moonlit light rather than pitch black. Operating at night is more like on Earth.

So, could you see? Yes, but not that well during the daytime. At night, Novoa Kiev is pitch black, whereas on the other side of the planet they get a little moonshine.

 

* Emissivity is probably closer to 0.5, but 1 is the assumption used. Both work but shifts the habitable band of Aurore slightly.

** Colin Dunn has changed this in his universe to 9.5 days. We ignore it as a clear error-of-fact. 

Realistic Interface Transport in (GDW) 2300AD

Introduction

The formulae in the Naval Architects Manual are a mess. The fuel required for orbit is given as, using the correct order of operations:

(1)

 

 and the time to orbit is given as:

(2)

 

Both these are nonsense. There was an attempt to correct (2) in Challenge 37's Three Blind Mice, but it was also wrong.

The cost of lifting a ton to orbit (of payload) is ca. Lv4,500* in a shuttle or rocket or Lv3,000 with a spaceplane, which is about 1% of the current cost (ca. Lv200,000 per ton on a Falcon 9 Heavy to LEO, whereas 2k3 launches seem to be to a higher orbit). This is about in line with the current optimistic projections of what launches with fully reusable rockets would cost. SpaceX optimistically thinks they can get the price down to Lv2,500 per ton to LEO, with a fully reusable vehicle, which is close to 2k3 numbers.

Fuel is Lv100 per ton, and so the cost of fuel is ca. Lv600 per ton of dry weight, and if the vehicle is 50% payload (and non-thrust fuel) then the cost of fuel is Lv1,200 per ton of payload, or 27-40% of the cost to orbit. This is roughly in line with projections for SpaceX Starship's percentage etc.

From general principles, a hydrogen/oxygen rocket launching from Earth will require ca. 5/6ths of its' initial mass to be expended as fuel (and oxidiser). The fuel fraction vs dry weight should thus roughly be 5x dry mass one one (up). The 2k3 formula is explicitly two way - lift to orbit and return.

The Fix

Without giving derivations, the following formulae are approximately correct:

(3)

(4)

Tonnage should probably be dry mass.

Time to orbit should be 8-10 minutes for an Earth sized planet. Any quicker and the accelerations are liable to injure anyone onboard. Slower and the vehicle incurs additional gravity drag, and will have to expend even more fuel.

Both rockets and rocket planes are listed as taking 1 h to reach orbit, whilst scramjets take 2 h and so do catapults. Since the stutterwarp zone is about 10,000 km above the surface of Earth, once you've spent ca. 10 minutes getting to LEO, the rest is likely the orbital transfer.

Spaceplanes with airbreathing engines can use these engines in the lower atmosphere, but they rapidly get too high to get any benefit from airbreathing or lift surfaces. An option is for a shallower ascent than straight up, but this increases aerodynamic drag losses (remember, that lift is diverted acceleration) and gravity drag losses. A typical spaceplane might get upto about 25-30 km altitude and Mach 5 (1.7 kps, ca. one Mongoose Traveller "burn") before having to engage the rocket engine. From that point the fuel consumption etc. is similar.

The equation is for a round trip, although the majority of the fuel (> 90%) is burnt in the ascent.

Oddly, in terms of time, the spaceplane should be the one that takes longer to reach orbit, by both the table and common sense. Ergo, reverse the lift values for shuttles and spaceplanes. The advantage of a spaceplane is that there is no 3+ G acceleration, and the ride is acceptable for untrained non-astronauts. As described, most cargo goes to orbit in shuttles, whilst people take spaceplanes. Spaceplanes with air breathing engines can likely get away without external boosters, even if they have an external fuel tank.

The Effect

Yes, going up and down the gravity well is more difficult, or rather it is as difficult as described in the main rules.

No starship is going to be SSTO. Lifting a starship requires stacking on boosters (if the engine doesn't generate enough thrust, i.e. time to orbit isn't 10 mins for a rocket). Visiting a planet almost certainly means using landing craft. The gut check is whether the craft has 1 MW of MHD thruster per 120 tons of dry mass. Most of the fighters make this (the Bufer being the exception), as does the Aconit. The Yinma Lander doesn't, nor does the Hayabusa, LC-20 etc.

Most landers will require at least an external fuel tank to reach orbit. A Yinma, Hayabusa, LC-20, Thorez etc. will need to be stacked on a booster.

This gives problems for the likes of Bayern, but where are all the long runways on virgin planets for a spaceplane or shuttle to land on? Where are the cleared, level landing sites for thrust landings? Landing on a virgin planet, without infrastructure already in place, is a major issue.

Stutterwarps in Orbit

"Stutterwarp vessels can also leave orbit without using conventional drives."

2300AD Director's Guide, p. 62

It is continuously stated in the GDW books that stutterwarp does work inside the dead zone, and does provide enough movement for orbital maneouvres, but not enough for landings. It is explicit that stutterwarp equipped ships don't need rockets to leave orbit.

From the point of view of a starship, there is a certain truth to this. When a starship inserts itself into an orbit with stutterwarp, and makes no reaction burn, the orbit must either crash into the planet (or enter the atmosphere and land), or leave the dead zone at some point. Without a reaction drive, a starship simply cannot actually achieve a circular orbit below the threshold altitude. Thus it would never need a reaction drive to break orbit. If necessary, it could insert into an orbit with a very low perigee to launch landing craft.

For landing on the surface, one can devise deadglide strategies what obviate the need for a reaction drive to land, but for taking off, the reaction drive is necessary, and probably it's needed to reach the stutterwarp threshold.

Hence, why older players get a little confused. The reaction drive is simply unnecessary.

 

* Note: this uses GDW Livres. Mongoose Livres are far less valuable, and pegged to the Imperial Credit.

The King Problem and How It Changed 2300AD

Preamble

I've been looking into historical stuff recently, and realised that many of the planets on the Colonial Atlas had serious flaws. The most egregious were Kie-Yuma (no planets can exist in the system), Kimanjano (explosive fuel-air mixture for an atmosphere), several worlds which are tide-locked but this isn't mentioned, and several worlds beyond the size for gas giant transformation.

I am aware that some people have played games on these worlds, as described in the Colonial Atlas, and would not want to change. Indeed, I think some changes should not be made, especially those caused by new observations. An example is that in 1989 it was found that Ellis' star is in fact a double star, which means the planet literally can't exist. However, if a true 3rd edition was ever to be written, I'd like the hard science to return.

King poses a particular issue, because the author actually rewrote the Human tech-level to make the planet work, and the author of the Mongoose edition pushed this revision to a logical conclusion, after stripping the DNAM tech of the dangers (which I revised here, to make follow the Mongoose rules). It serves as a wonderful example of the dangers of making an apparently small change to a setting. The DNAM's themselves changed during GDW's run (see appendix 1).

However. you are, of course, supposed to play the game as you see fit. I'm aware that I'm a stickler for consistency, scientific accuracy and continuity.

Introduction - Before King was Defined

In the pre-Colonial Atlas 2300AD, King was a rich planet colonised by America and Australia in 2194 and 2196 respectively. (1st ed. Player's Manual, 16 and the colony table) It was not designated a high-gravity planet, or one with a toxic atmosphere. At the same time, transfecting Humans to treat genetic disease was a new and experimental development in the year 2300. (1st ed. Player's Manual, 14)

In the non-canon Traveller's Digest issue 10 (September '87), William Connors gave King a toxic sulfurous atmosphere, and stated the Pentapods, at the Life Foundations' request, developed atmospheric filter symbionts (AFS). Of course, as a Pentapod invention, this places the AFS' introduction into relatively recent times, because the Pentapods weren't contacted until recently.

The high-gravity, tantalum motherlode King then appeared in William Connor's write-up in the Colonial Atlas (February '88), and it required a complete rewrite of Human genetic engineering. There is, however, a huge problem.

King is a Gas Giant (+)

When planets form, they do so from the local material, which is mostly hydrogen and helium. As they condense, their gravity will pull heavier materials into them, but cannot hold onto lighter ones. The temperature and solar winds have an effect, but in the habitable zone, these are roughly similar across all stars since the habitable zone is defined by temperature.

With smaller protoplanets, the gravity is insufficent to hold hydrogen and helium, and these gases escape from the planet. This leads to rocky or icy planets. If the gravity is strong enough to hold onto hydrogen and helium (which are the bulk of matter), the planet becomes a gas giant, and continues to suck in hydrogen and helium from the environment, snowballing into even bigger gas giants.

For worlds in the habitable zone, the boundary between these two states is about 1.35 G. Worlds with gravity below ca. 1.35 G loose their hydrogen and helium and become rocky or icy planets with a surface. Those with greater than ca. 1.35 G but less than ca. 1.6 G retain helium, not not hydrogen, and become failed cores (or Triton-type planets). Those with greater than ca. 1.6 G become gas giants, and may snowball into brown dwarfs.

King is far beyond this figure.

Now, GDW had sensible rules. In the 1st edition world building rules the limit to non-gas giants was given as 4 Earth masses, and that planets that had hydrogen-helium atmospheres were gas giants. Now, the mass and gravity tables changed between 1st and 2nd edition (the King gravity uses the 2nd edition table), but the minimum molecular weight retained (MMWR) didn't. The 1st edition rules lacked the snowballing rules, and these were added in the 2nd edition along with clarification that all worlds with MMWR of 4 or less were gas giants:

 

Connors made the largest and heaviest possible world under the planet generation system, which required rolling six 6's in a row on d6's, and then a 10 on a d10. The chances of this extreme roll were 1 in 466,560. The MMWR is zero (0) and thus the planet is a gas giant, and should roll for snowballing. Roll d6-2, and double diameter that many times. If another 6 was rolled then the diameter would be multiplied by 2^4 = 16 times, and King is a 480,000 km diameter gas giant.

The GDW planet creation system makes King a gas giant at the supplied values. 

How Big Could a Terrestrial King Be? What Would It Be Like?

To keep the spirit of the original, we need King not to bloom into a gas giant, but rather collapse into a terrestrial planet. At a density of 1.3 Earth's, the maximum diameter is 13,000 km, or just a bit larger than Earth. This would give a mass of 1.4 Earths and a surface gravity of 1.33 G. It is essentially the most extreme non-gas giant in the life zone the system can generate.

(As an aside, the size of icy cored planets was substantially increased in the 2nd edition)

King's star is a K7V. The actual star (Groombridge 1618) is more luminous than the 2300AD star, but we use 2300AD values. We'll use the stars' real mass of 0.67 solar masses. This is a small orange dwarf, and since the mass of the star is below 0.7, and since the planet is in the life or inner zone (actually inner, see below), it is tidally locked to the star. The distance from the star is not defined (but can be found from the orbital period, see below), but it is less than 0.32 AU, and this planet and King are in the life zone.

The given luminosity of the star is 0.057 of Sol, which is weak for a K7V (average about 0.1 of Sol). By the GDW world creation system the optimal distance is 0.24 AU, the inner limit is 0.17 AU and the outer limit 0.35 AU. From the second planets location, the system would generate from 0.15 to 0.24 AU, which places King at inner part of the life zone. However, since we have the length of a year, if we assume the mass of the star we can calculate the orbital distance using Kepler's 3rd law. At 0.67 solar masses, the orbital distance would be 0.14 AU, which places King in the inner zone, not the life zone. Solar intensity is 0.057/(0.14)^2 = 2.91 of Earth. This means the planet would have lost all water, and developed into a scorched rock. This is the actual definition of inner-habitable-outer zones.

On the topic of habitable zones, the formula in GDW is based upon the assumptions in Doles' 1964 book, but the numbers in the world generation table is a bit narrower. Doles was probably a bit optimistic, and spinning worlds in the 72%-86% (ish) of optimal are likely to only have water at the poles, and worlds in the 120%-145% (ish) of optimal range are likely to have massive glaciation, and liquid water only at the equator.

The CA write-up says there are only two zones on the planet King that are habitable. For a rotating world this would be correct, and they'd be the two polar regions. The incident energy from the star depends on the sine of the angle of incidence (i.e. latitude). Since temperature equivalent is the 4th root of the energy, the equator is hotter than the poles with a spinning planet. However, with a tide-locked planet this causes the hot pole to be hottest, and the temperature to drop as we head out to the terminator.

Back in the 80's it was assumed that only the twilight zone of a tide-locked planet would be habitable. This is only true of tide-locked planets in the inner zone. For planets in the life zone, the ring of habitability is going to be on the day side, especially if we have a lot of liquid water, which King does (67% of the surface is liquid water). However, King is in the inner zone, and the solar intensity is huge. The hot poll is well above 100 oC, and the dayside is a scorched desert.

Being technically in the inner zone, the planet would have had a runaway greenhouse effect, and be a Venus type world. Ergo, we have to move it outwards.

A Revised King

Since we want to have a real colony, we have an issue. The star's luminosity condemns it to being a tide-locked desert world, without a breathable atmosphere (because oxygen comes from plants). We simply cannot have a terrestrial world with an oxygen atmophere around that star. However, if there is still ice on the cold side, we can perhaps build domes over subterranian mines, and supply an atmosphere by hydrolysis, or even from the ore they're smelting, assuming they have relatively pure oxides.

The planet could be high gravity (1.2 to 1.3 G), but it would not require any genetic adaption.

Domes would be in the twilight zone, sited to be over ore deposits and close to a glacier. Each dome would likely be based around a nuclear or fusion reactor (early ones nukes, fusion is a later invention) which provides the power to sustain an atmosphere. Under the dome, mines are sunk and ore harvested. Old mines become living spaces.

Expeditions to the cold side glaciers to bring back water would be a major economic activity. The water is needed not just to breath, but to be made into rocket fuel for leaving the planet, and taking the metals to orbit. Ultimately, pipelines may be built, with colony domes on the night side whose only economic activity is ice-mining.

This world's domes would resemble the hives of some sci-fi.

How DNAM's Changed 2300AD

Colin Dunn was (and is) far more interested in cyberpunk and transhumanism than the hard sci-fi of the 2300AD. Indeed, he once wrote he never played 2300AD proper, but rather used elements of it in his CP:2020 campaign. It is of no surprise then that he focused in on the cyberpunk elements, including the DNAM's, and magnified them. This evolved over several iterations of the Mongoose editions and is, to my mind at least, antithetical to the original. That said, GDW did this to themselves by trying to shoehorn in cyperpunk.

Thus, whilst in the original DNAM's didn't exist for much of the run, and then were a special case that was being downplayed over time, in the Mongoose edition were get an explosion of DNAM's. In fact, Colin tried to make every single colonist a transhuman. This did not go down well with some, and I intend to look at this when I compare real genetic engineering with his DNAM's.

 

Appendix 1: DNAM Development

In fact, DNAM's changed slightly over time. As mentioned, DNAM's were, until the publication of the Colonial Atlas, actually written up as beyond Human technology. The Colonial Atlas introduced them, and around the same time Bayern came out, which was also written by Bill Connors. There is a King born character in Bayern. However, that character does not appear to be a DNAM when compared to the second edition boxed set.

In the 2nd edition, a DNAM character is included in the solo adventure "Terror's Lair" They, and another DNAM encountered, cannot breath normal air, and have to wear rebreather masks. (DG, 19) The character of Diane Kamahmo on the Bayern doesn't have to wear such a mask, which would be a major hazard for her and make her an ineffective officer.

As an aside, Bayern and Ships of the French Arm are in conflict with respect to the Vogelperspektive, because the ship hadn't left the near French Arm, and hadn't done any real exploring as of 2300.