Expanding Atmosphere Types

[Santiago]

Been there done that- In my personal mod I added chlorine, nitrogen, sulphur dioxide, helium and neon. I wasn't going for the realism that you are. But don't rule out the noble gases- they are used as exotic diving gases- Argon and Xenon are too narcotic, Krypton causes dizziness and Radon is radioactive. Neon though expensive is a good replacement for helium.

Trimix is also good as it is a mix of O2 He and N2.

Hydrogen sulfide is a good choice but causes smelly planets

If you're just looking for other possibilities;
Nitrous Oxide---A very happy planet

Ethylene---ancient Egyptians, who would gas figs in order to stimulate ripening.

Sulfur hexafluoride---SF6 is the most potent greenhouse gas, with a global warming potential of 22,200 times that of CO2.

Hydrogen chloride---Very corrosive forming HCl acid in the presence of water/humidity

Nitrogen Dioxide---This reddish-brown gas has a characteristic sharp, biting odor. NO2 is one of the most prominent air pollutants and a poison by inhalation.

Vinyl chloride monomer---Until 1974, VCM was used in aerosol spray propellant. Prior to the removal of VCM from hair spray the accumulation of vinyl chloride vapor in hair salons may have exceeded the NOAEL (NO Adverse Effect Level) exposure guidelines. Just an odd fact.

Deuterium Gas---Don't know much about this one

Phosgene---This gas gained infamy as a chemical weapon during World War I, but it is also a valuable industrial reagent and building block in organic synthesis. It is colourless, but can appear as a white or yellowish haze when released into air, Chlorine light.

Silane---chemical compound with chemical formula SiH4. It is the silicon analogue of methane. At room temperature, silane is a gas, and is pyrophoric — it undergoes spontaneous combustion in air, without the need for external ignition. Silicon based life forms?

Hydrogen cyanide (HCN)--- is a colorless gas with a faint bitter almond-like odor. Very poisonous.

Dimethyl sulfide--- In vapor form it is produced by cooking of certain vegetables, notably corn and cabbage, and seafoods. It is also an indication of bacterial infection in malt production and brewing,and a disagreeable odor. DMS is the most abundant biological sulfur compound emitted to the atmosphere. Emission occurs over the oceans by phytoplankton.

[StarShadow]

Also, generally speaking, as far as the atmosphere types go, wouldn't they just specify what the 'majority' gas is? Although going by that, the earth is a nitrogen planet since our atmosphere is about 78% nitrogen and only about 20% oxygen. In any case, with the exception of 'none', I don't think any planet has an atmosphere that consists solely of one gas.

[narf poit chez BOOM]

Variety is the spice of life.

[Renegade 13]

I think H2S (Hydrogen Sulfide) would be a good choice, given how it's possible to be used to slow metabolic processes of mammals to an extreme level. The race that breathed it could be said to possess an extremely low metabolic rate, and evolved over time to utilize it instead of oxygen as their home planet's atmosphere became slowly innundated with H2S.

[dmm]

Slightly off topic:
It seems to me that most solar systems should have LOTS of tiny no-atmosphere or thin-atmosphere planets, especially around the fringes. In other words, a Kuiper belt.

Also, if you're going to aim for realism, then planets must have temperature attributes. I would think that the extremes of temperature would be more important for colonization than atmosphere type. If a planet's climate at its equator is like Antarctica in winter, then you're not going to get undomed colonies of humans even if the atmosphere is nitrogen/oxygen. Conversely, if a planet is very Earth-like except that it has little atmospheric oxygen, then colonists just need to carry an O2 supply/generator when they go outside -- domes aren't really needed.

[Fyron]

Planets have gravity, temperature and radiation values, but they don't have any actual effect.

[Baron Munchausen]

Fyron said:
Planets have gravity, temperature and radiation values, but they don't have any actual effect.

Despite months of hounding MM to make them have an effect.

[dmm]

I forgot some stuff:

Huge planets should always have several Tiny planets nearby. These would represent very large moons like Titan.

Making None atmospheres common (in order to be more realistic) would mean a big advantage for None "breathers." So to compensate you'd have to make sizeable None planets extremely rare, which is probably realistic anyway. (That would make None races very interesting to play. Lots of room for expansion in every system, but lots of planets to defend.)

If planets had temperatures, these would generally get more frigid the further away planets were from their star.

And while I'm talking about realism: what's up with having two (or three!) main sequence stars close together, at the center of a star system, surrounded by planets?

[Fyron]

How else would you do binary stars? There isn't a whole lot of room to place them far apart.

The planet temperatures do get colder as the planets get farther away from the star, based on type even (in FQM anyways). Its a nice geometric formula, with distance^2 instead of the silly distance used in stock:

Name := Formula Planet Terr Temperature
Formula := MAX(-240, 100 - ([%HexDistanceToCenter%] * [%HexDistanceToCenter%] * 3) + Random(-50, 25)) + (([%NumberOfStars%] - 1) * 50)

Name := Formula Planet Ven Temperature
Formula := MAX(-240, 360 - ([%HexDistanceToCenter%] * [%HexDistanceToCenter%] * 3) + Random(-50, 25)) + (([%NumberOfStars%] - 1) * 50)

Name := Formula Planet Moon Temperature
Formula := MAX(-240, 80 - ([%HexDistanceToCenter%] * [%HexDistanceToCenter%] * 3) + Random(-50, 25)) + (([%NumberOfStars%] - 1) * 50)

Name := Formula Planet Ice Temperature
Formula := MAX(-240, 20 - ([%HexDistanceToCenter%] * [%HexDistanceToCenter%] * 3) + Random(-50, 25)) + (([%NumberOfStars%] - 1) * 20)

Name := Formula Planet Gas Temperature
Formula := MAX(-240, 40 - ([%HexDistanceToCenter%] * [%HexDistanceToCenter%] * 3) + Random(-50, 25)) + (([%NumberOfStars%] - 1) * 25)


Compared to the lamo (excessive) stock formula:

Name := Formula Planet Temperature
Formula := IIF([%HexDistanceToCenter%] <= 3, 500 - ([%HexDistanceToCenter%] * 100) - Random(0, 100), IIF([%HexDistanceToCenter%] >= 7, 0 - ([%HexDistanceToCenter%] * 20) - Random(0, 50), Random(-50, 50))) + (([%NumberOfStars%] - 1) * 100)

[Captain Kwok]

Woohoo for the inverse square law of radiation.