Alternate Planets, Suns, Stars, and Solar Systems Thread

Post all material relating to the physical properties of alternate planets (climate, geology, geography,...), alternate suns/stars, and alternate solar systems (planetary properties, Goldilocks Zones,...) here!

Also, questions to those materials are to be asked here.

@Dorozhand: Here, you can post about Huitzilopochtli and you should also consider copying all Huitzilopochtli material over to this thread. What do you think?
 
Some changes to the Solar System provides us with three habitable world's. :p

Solar System:
Mercury

Mars / Moon / Moon
Mars is in a closer orbit coupled with a full-sized moon and a diminutive asteroid as well as the positive effects of an active magnetic core have made incredible changes to Mars. No longer a dying world the red planet is still red, but green and blue also invade the surface. With a gravity about half that of Earth's, and a atmosphere roughly comparable to our own Mars is a lush planet with large Iron-rich deserts, and the solar system's largest active super volcano.

Mars itself has an day/night cycle of 25.75 hours, nearly identical to that of the Earth.

Earth / Moon
- Same as modern day

Venus / rings / Moon
The twin of Earth, Venus is the fourth planet from the sun and is very temperate - a little warmer then Earth because of the more robust greenhouse gas effect, but still quite habitable.

Scientists believe that the ring system of Venus was formed after two Moon-sized object collided hundreds of millions of years ago. The asteroid debree couldn’t reform into a moon, and instead became trapped in a circularized orbit around the planet Venus. Venus is the only Terrestrial planet in our solar system to have developed rings like the outer gas giants, and even though the rings have consolidated their orbit at an equatorial 125 km circular orbit they are visible from almost everywhere on the surface of the planet.

Venus itself has a uninhabitable moon, approximately the same size as our own Moon. This moon has over the eons stabilized the rotation of Venus, and allowed an 28 hour "day." Venus is a wet jungle world, drier then Earth but wetter then Mars or Vega. Scientists have calculated that 65% of Venus is covered by water, and that ninety-three percent of the water on Venus is salt water. Air pressure and Gravity are both approximately 85% that of "normal sea-level" conditions on Earth.

Vega / captured asteroids
Vega is the Mars analogue planet, dead or dying - just on the border of the inner habitable zone, and close enough to the asteroid belt to guarantee the capture of a number of asteroids from the main belt Vega is about as inhospitable as they come. Vega has no active core, and it has a surface water percentage of 15% liquid water on its surface which is quickly evaporating along with the decaying atmosphere.

Asteroid Belt

Jupiter

Saturn

Uranus

Neptune

Pluto
 
Also, any information related to xenobiologies (boron- or silicon-based, ammonia-, ethane- or HF-dissolved, nitrogen-breathing or using arsenic,...) should go here, too, unless it is from published fiction.

The Race, e.g., belongs in some other forum, but the xenobiologies invented by DOrozhand in the Huitzilopochtli system belong here, too!
 

Dorozhand

Banned
Huitzilopochtli - Metal-rich Class-B blue star about 8 times the mass of Sol. Bathes everything in the system in a pale-blue glow, a lot of UV radiation, habitable zone very far out but also very wide. Metal rich composition allowed for a good amount of terrestrial planet formation. Rather long estimated lifetime of 7 billion years allowed for native life to actually form and evolve.

Intraxiuhtecuhtlian Asteroids (Scorched Belt) - As the name implies, these asteroids are extremely hot half-molten lava-balls. Correspond roughly to the theoretical "Vulcan Asteroids" once thought to exist within Mercury's orbit.

Xiuhtecuhtli - Innermost planet, about the mass of Terra. Incredibly hot, covered in seas of liquid metals and minerals and bathed in the haze of an atmosphere of Sulphur, Mercury, and Sodium vapour.

Mixcoatl - About the mass of Mercury, and of a similar temperature and composition, though slightly less dense. High albedo makes for a brightly visible body.

Huixtocihuatl - Of great interest to scientists, geologists, and miners alike is this planet, which was apparently once covered in ocean. Orbital instability due to proximity to Teotlale, set off by an impact sent it spiraling disastrously inwards about 2 billion years ago. Once outside of the habitable zone, its oceans boiled off, and all that's left now is an immense, world-spanning salt flat. It's about .85 the mass of Earth and its orbit is extremely offset from the rest of the system's plane. The impact which sent it to its fate also gave it a moon, Nextepehua, the god of ash.

Intrateotlalean Asteroids (Tempest Belt) - Believed to be the ejecta from a large impact on Malinalxochitl which greatly reduced the moon's size, these asteroids are unstable and chaotic. A great hazard to anyone attempting to mine them or even travel through them. It is lucky that Teotlale's three moons and Atlacamani's freakishly large moon acted as impact shields, or life may have been extinguished there.

Teotlale - The first world within Huiztilopochtli's habitable zone, though barely. Bombarded by UV radiation, the harsh blue disc in the sky is an unmerciful mistress. The baked sand is nearly lifeless on the surface, but underground bacteria thrive. Multicellular life tightly hugs little oasis ponds which spring from the earth, and large plants with orange fan-like leaves are as big as life gets even there. The only significant area of surface water are two small lakes almost on top of the north and south poles, each less than about 500 km in surface area and .5 km deep. They are the only places which host significant permanent animal life. Tiny herbivores and shelled, gelatinous cephalopods which evolved in geothermal vents, slowly creeping to the surface over a billion years. Teotlale has no plate tectonics, which probably saved the life as volcanism would have belched forth CO2 and the world may have ended up like Venus.

Teotlale has three moons.
-Nexoxcho
Stained red with iron oxide, spectacular from the surface. Only about 45 km in size.
- Malinalxochitl
About 200 km wide. Used to be larger, but an oblique impact threw off significant mass and created an asteroid belt in the process.
- Chalchiutotolin
This one is interesting. It's about the size of Europa, and has a thick atmosphere. It's covered in lush jungle rainforest which looks like paradise, or early sci-fi's conception of Venus, from orbit. You don't want to go down though, as the comparison to Venus doesn't end there. Everything is poison. The life of the moon uses Hydrofluoric acid as a solvent, and oceans and an atmosphere of the stuff cover the world in a greenish haze. Exobiologists had a field day studying it, and the deaths were almost worth the knowledge that they gained.

Atlacamani - Atlacamani is squarely in the center of the habitable zone, and thus has a mild, temperate climate similar to earth. The planet is .95 the size of earth and slightly less dense, this lighter gravity makes the world a particularly comfortable place to live. Its surface is mostly land, with 40 % covered by seas. Its plate tectonics is somewhat more active than earth's, and this produces higher mountains and lower trenches, there is even a range thrust up by a corona. It is not a metal-poor world, its metal content mostly consists of aluminum, Vanadium, and other lighter metals, with a bit less Iron.

Its biosphere is rich and varied, containing animals, fungi, other phyla harder to define, and plants. As with most plant life in the system, Atlacamani's is bright orange to scarlet. The planet possesses polar, tundra, steppe, temperate, and tropical temperature zones, and rain is very common. Cloud cover and a slightly thicker atmosphere than earth prevent a lot of the harshest of the blue sun's rays from irritating human eyes. This also produces spectacular sunrises. One view of an Atlacamani sunrise, as the azure orb stains the sky with shades of purple, magenta, aquamarine, and maroon is often enough to convince visitors to stay. The day is about 27 hours long, leisurely compared to earth without being oppressive like Teotlale's 38 hour days.

Atlacamani has one moon, but what a moon it is! Chicomecoatl is the size of Ganymede and appears as a spectacular light-brown disc in the night sky, thrice as large as Luna. It even possesses pockets of single-celled life of its own in its soil and deepest caves, and is believed to have once had oceans of liquid water. It was likely created by a gargantuan impact which occurred very soon after the planet's formation, Atlacamani's more elastic materials allowing for it, though barely. The moon accreted more dust after it formed, growing larger still. It is named after a god of agriculture, as it is vital in maintaining Atlacamani's axial tilt of 34 degrees, and its seasons which are created thereby.

Nonohualco - This is the third and final inhabitant of the Goldilocks zone, and is quite frigid. Its land mostly consists of gloomy, windswept tundra, containing cold-resistant life-forms, although oases of warmth near hot-springs on the geologically active world produce pockets of rich biosphere. Its atmosphere is thinner than earth's, about Thibetan levels at the surface, at least tolerable to humans. Its temperature averages 12 degrees Centigrade, but is fairly uniform throughout the world due to geologic activity. Seas cover about 15% of the surface, and teem with life.

Nonohualco possesses two moons. One, Cipactonal, is almost the size of Europa and has an atmosphere similar to the parent world, although its life is more rudimentary. The other, Tepeyollotl, is geologically active like Io due to tidal stress between Nonohualco and Cipactonal, and possesses extremely tall mountains.

Huehuecoyotl - The last of the inner planets, there is very little to say about this Mercury-sized lifeless ball of rock other than a peculiar quantity of Vanadium in its crust.

Intraxochipillian Asteroids (Great Belt) - This is a massive belt of asteroids stretching from the edge of Huehuecoyotl's hill sphere to Xochipilli. The massive gas-giant's tidal forces prevent any bodies larger than Triton from forming. Rich in metals, it is fodder for mining operations.

Xochipilli - A gigantic gas giant 2.3 times the mass of Jupiter, named after the Aztec god of jollity and contentedness. It contains a lot of Methane, which, along with the light of Huitzilopochtli, gives it a staggering bright blue hue. Storms larger than the great red spot rage all across its surface. One is nearly six times the size of Atlacamani. Two spectacular rings orbit the planet, the remnants of a moon collision.
Of its many, many satellites (all but the two largest named after gods of wine), the most interesting are:
Mayahuel - Twice the mass of Callisto, it shepherds the two great rings, riding almost exactly between them.
Patecatl - The smallest body in the system to independently evolve life, it is about the size of Triton. Tidal forces warm ice below its surface, which resulted in a Europa-like ocean forming. Life is very simple, mostly orange algae clinging to the bottom of the ice. Small animals have evolved from polyp fungi at the warmest regions of the equator and at the bottom of the ocean at vents, but reach no more than a decimeter in size.
Camaxtli - A blue moon. Tidal forces between great Xochipilli and the Mars-sized Xolotl result in a geologically active body and significant atmosphere. Greenhouse gasses trap heat, and create a climate almost like earth. The world, .78 the size of earth, is an oasis of life in the cold outer system, oceans covering 82% of the surface and continents rich with great orange forests.
Xolotl - about the mass of Mars, Xolotl is a dry but life-bearing moon. Tidal forces keep it just warm enough, though greenhouse gasses are less concentrated and plants are black, in order to get as much of the star's light as possible.

Ometeotl - A binary gas giant. Two planets, one slightly larger than Jupiter and one a bit smaller, orbit one another at a common barycenter. The larger, Ometeotl A, is pale blue, while the smaller, Ometeotl B, is an aquamarine colour, like Uranus but slightly greener. Both worlds rotate very fast, and have great storms the size of planets.
The moons of Ometeotl are all lifeless except for Ethane covered Xocotzin. It contains lakes of liquid hydrocarbons which, remarkably, have produced fragile colonies of bacteria which use it as a solvent. Xocotzin is also remarkable for another thing. It possesses its own tertiary satellite called Tlazolteotl.

Ehecatl - A gas giant consisting mostly of hydrogen, helium, methane, and, most strikingly, Ammonia. The planet is over 7% Ammonia! How this came to be is unknown, but its consequences shook the world of biology to its core.
Tloxipeuhca, a world about the size of Mars, possesses oceans of liquid Ammonia. These seas have produced an entire fully realized biosphere using Ammonia as a solvent in lieu of water. Ammonia lakes, rivers, storms and hurricanes, and continents covered in Ammonia life! Animals, plants, fungi, and a kingdom of fungi-like animals which use alkali metals and oxygen dissolved in the water to produce energy and recycle waste. Boron-based biochemistry allowed for variable divergences and sped up the process of evolution. Fish, cephalopods, vertebrates, and even land megafauna of phyla and purpose wild and exotic formed. An exobiologist's Eden. It also happens to be one of the only places known with an easily accessible natural supply of Rubidium and Caesium. The moon also has a tertiary satellite of its own.
Perhaps the most staggering thing about Tloxipeuhca is the presence of intelligence. A land-dwelling, radial, vertebrate species with a gelatinous body encased in calcium borate armor plates which used evolved "hands" (branched crinoid-like tendrils) to manipulate its environment, use tools, master combustion (possible on Tloxipeuhca), and spread across the world. Great care is taken not to interfere with their cultural development, only to observe from orbit or with robotic probes. Any rogue mining company which attempted to exploit the moon in any but the most controlled and supervised methods (tiny robotic probes in the oceans to extract Rubidium and Caesium) would face an immediate liquidation of all assets and a war of extermination against its leadership. Even what little mining that is allowed is planned to be completely discontinued at the first sign of transoceanic voyaging on the part of the sentients.
Tloxipeuhca is the last world in the system to harbor life.


Xantico - This gas giant, about the size of Neptune, contains a peculiar quantity of Sodium, which stains its clouds magenta. Other than that, it is a garden variety gasbag. Its moons are all lifeless. Two of them, Tlatlauhqui and Nanahuatl, are of interest in that they contain large quantities of liquid Nitrogen.

Ixquimilli - One of the two "Outer Terrestrials", considered planets by virtue of their Mercurian masses, they were likely moons ejected from either Xantico or Zacatzontli. Ixquimilli has a high albedo, making it bright in the night sky of Atlacamani. The world is frozen solid nitrogen, water, and ammonia ice, with a rocky core and some deposits of Iodine, which hint at an origin with Zacatzontli.

Oxomo - less visible than Ixquimilli, but larger. It is also frozen solid, and one of the coldest objects in the system.

Zacatzontli - A gas giant, slightly smaller than Neptune, containing some quantity of Iodine, which stains its clouds purple. A lonely world at the dim edge of the system, named after the god of the night-road. Beyond it lay the Outer Belt. Its moons, while not frozen solid, are very cold. Itzpapalotlcihuatl and Cihuacoatl are famous for having geysers of liquid nitrogen.

Transzacatzontlian Belt (Outer Belt) - A lonely field of ice-balls no larger than Luna dwells here. Very unexplored, but may contain resources yet untapped.

One last world, the Earth sized Miquiztlitecuhtli is a dim marker of the boundary of the system. No one knows just how it got there, or exactly what it's made of, but its mass has sparked debate over whether it should be classified as an Outer Belt Object or the 15th Planet.

The Comet Sphere - like Sol's Oort Cloud. The origin of comets.

http://i.imgur.com/dlrjIcA.png
 

Dorozhand

Banned
I have some rather scientific questions on the system of Huitzilopochtli...

1) Why so many planets? I find that good, really good, but do such stars accrete so many planets, or was it just done for creativity's sake?

2) Huitzilopochtli is a blue star. What does that mean for distances? How far are the planets from the sun, especially Atlacamani? How far is the innermost Xiuhtehcutli? There are some systems were planets are really close, or really far, so it could be anything between a tiny fraction of an AU and 1-2 AU for Xiuhtecutli.
The same applies to all other planets, e.g. Atlacamani could be 1 AU away just as Earth is, or much less, or much more if Huitzilopochtli is hotter. The same for all other planets... and: How far is Zacantzontli?

3) What rotation periods ("days") and orbit periods ("years") do the planets have? Is the Atlacamani year similar to the Earth year, or longer? Or shorter? And, on this note, why would you see a 38-hour-day as it prevails on Teotlale as "oppressive"?
What days and years do the life-bearing moons have in relation to their primaries?

4) How high are the highest mountains, how deep the deepest trenches on Atlacamani? How high is this "Corona range"? What is the highest mountain on Tepelloyotl?

5) Of what substance is the xenojungle of Chalchiutotolin made in order not to be attacked by a HF atmosphere? Is such a leaf poisonous itself, or is it just the HF atmosphere and "rivers" and "oceans" that are? Why is the xenojungle green, and what colour do the seas have?

6) Regarding Tloxipeuhca: Why would the Atlacamanians would to exploit the world at all? For what valuable minerals would they do that? Or are you referring to Humans? The same with "would face... liquidation of their assets and a war of extermination...": By whom? By the native Tloxipeuhcans, by Atlacamani, or by us Terrans? Or by a combination of the three?
Also: Both Rubidium and Cäsium are, as you can see from Wikipedia, highly reactive. So why would you mine the two elements, for what use would Atlacamanians use such reactive substances which (on Earth, at least) need to be stored under inert gases or petroleum oil? To form some compound?

7) What temperatures (surface) do the living (and, if possible to say, also the non-living) worlds have? We know that Atlacamani is more or less Earth-like (hotter or colder?), and that Nonohualco has 12 C. What temperatures are there, e.g., on Chalchiutotolin, and the same basically for all other (living) worlds?

8) What about gravities? How strong or weak are they?
Excellent questions.

1) The star is much larger than Sol, and just as metal rich. More material for planet formation.

2) Huitzilopochtli, being a type B, is more powerful and luminous than Sol by a large margin, about 900 times more luminous to be exact. The temperature range is on a much larger scale, and the solar wind blew dust farther out.
Even blazing Xiuhtecuhtli is over 3 AU from the star
Mixcoatl is 10 AU
Huixtocihuatl is 18
Teotlale is 24
Atlacamani is 32
Nonohualco is 38
Huehuecoyotl is 55
Xochipilli is 90
Ometeotl is 200
Ehecatl is 390 (radiation here roughly somewhere between Saturn and Uranus)
Xantico is 551
Ixcuimilli is 640
Oxomo is 690
Zacatzontli is 740
Miquiztlitecuhtli is over 2000 AU!

Light and material was thrown farther out. There was quite a bit more of it to begin with though (the star formed in a nebula which possessed already a significant degree of metal content), so planets of good size coalesced in roughly the same timeframe.

3) The days of the terrestrials are similar to relative earth equivalents. Xiuhtecuhtli is tidally locked

Mixcoatl rotates slowly

Huixtocihuatl is an oddball, with a retrograde rotation due to the orbital shenanigans that killed it and gave it a moon

Teotlale's day of 38 hours I saw as "oppressive" simply because it's a long time to spend in gruelingly hot temperatures (an average of 48 degrees Centigrade) that bake the ground sizzlingly hot by afternoon. Standing in the open you'd have a bad sunburn in minutes or even seconds

Atlacamani's day is slightly longer than earth, but the average temperature is also slightly colder, so it gives the day's character a more laid back feeling

Nonohualco's day is shorter than earth, at about 21 hours, creating strong polar catabatic winds which gouge spectacular features in rocky uplands. Like North Dakota's badlands on a continental scale

Huehuecoyotl's day is about 19 hours

The gas giants have short rotations of about 9 hours on average. Their moons are mostly tidally locked, except for the outermost ones, which sometimes have independent rotations of their own. The outer moons of Ometeotl in particular have "days" averaging about 40 hours long

4) The highest mountain on Atlacamani is a peak of 34,000 feet above datum in the corona range (a region of crust being thrust upwards by plates converging from all sides at once). Barring the corona, the highest is a shield volcano in the southern hemisphere of about 32,000 feet. Barring that, the highest is 30,000 feet. The ever so slightly lower gravity and more vigorous tectonics allows for higher mountains.

The lowest point on Atlacamani is the bottom of a sea trench 10 miles below datum.

The highest mountain of Tepeyollotl is a gargantuan peak rising 15 miles above the world's mean elevation. Elastic materials stretched by tidal forces and a semimolten interior.

5) Naturally occurring polytetrafluroethylene chains form the basis of lipid-like substances that allowed the formation of cell membranes. The formation of FNA, a repeating chemical based on sequential units of complex organofluorine molecules bound by Vanadium and Arsenic compounds allowed for the coding of genetic information. The seas are a deep blue-green from orbit and there is a greenish haze due to yellowish hydrofluorine mixing with the blue light of Huitzilopochtli. The plants themselves are yellow to orange, with some magenta mixed in. Green plant trunks and stems are due to HF in their vascular systems. Being based on Teflon and other Organofluoriness, and filled with HF, they are quite poisonous to carbon life.

6) Human colonists in Atlacamani as well as the human government based from Terra. Chemical companies would exploit the natural supply of Rubidium and Caesium if allowed to do so, and would endanger local life. Humanity considers Tloxipeuhca a priceless marvel that should be handled with the utmost care possible. Any chemical company that tries it would face a war of extermination from the Terran army tasked to protect the world.

7) Xiuhtecutli's temperatures are in the thousands of degrees Centigrade

Mixcoatl's average is Mercury-like

Huixtocihuatl's is around 120 degrees Centigrade

Teotlale's, as mentioned, is about 48 C, Chalchiutotlin's is around 80 C

Atlacamani's is about 16 C

With Nonohualco I overestimated my head conversion :eek:. It's meant to be more like 6 or 7 degrees C

Huehuecoyotl is about -34 degrees C

Camaxtli is a balmy 17 degrees

Xolotl is about 3 C

Tloxipeuhca's temperatures are around -60 C

Ixquimilli and Oxomo have temperatures nearing the range of 30 Kelvin, colder than Triton

8) Xiuhtecuhtli's is about earth's

Mixcoatl's is Mercurian

Huixtocihuatl's is a bit less than earth's

Teotlale is 1.2 times more massive than earth

Atlacamani is .95 of Earth's mass and less dense. Gravity is comfortably less powerful without being crippling to anyone returning

Nonohualco is .89 as massive of earth

Camaxtli's is only three quarters as pwerful as earth

Xolotl's is a 1.4 times more than Mars

Tloxipeuhca has Martian gravity
 
Last edited:

Dorozhand

Banned
Complete map of Tloxipeuhca

Some features are named after celestial bodies, which kind of gives them a multifaceted meaning

Ammonia9.png

Ammonia9.png
 
Last edited:
One question remains unanswered, Dorozhand:

What year lengths do the planets, especially the living ones, have?

Also, you wrote about a "Terran army sent to protect [Tloxipeuhca]". What equipment is used to a) survive the temperatures and b) live and sustain a presence on a world made of Ammonia? Must everything be imported from Terra (possible if we are advanced enough)? Or can you live with no, or few, imports on Tloxipeuhca?

By the way, is it poisonous or what would (probably) happen if you just drunk from the liquid ammonia ocean?
 

Dorozhand

Banned
One question remains unanswered, Dorozhand:

What year lengths do the planets, especially the living ones, have?

Also, you wrote about a "Terran army sent to protect [Tloxipeuhca]". What equipment is used to a) survive the temperatures and b) live and sustain a presence on a world made of Ammonia? Must everything be imported from Terra (possible if we are advanced enough)? Or can you live with no, or few, imports on Tloxipeuhca?

By the way, is it poisonous or what would (probably) happen if you just drunk from the liquid ammonia ocean?
1) A Xiuhtecuhtli year is about one Terran year.

A Mixcoatl year is 12 Terran Years

Huixtocihuatl's year is about 27 TY

Teotlale's year is 41 TY

Atlacamani's is 64 TY

Nonohualco's is 84 TY

Huehuecoyotl's is 140 TY

Xochipilli's is 311 TY

Ometeotl is 1030 TY

Ehecatl is 2600 TY

Xantico is 4400 TY

Ixquimilli is 5600 TY

Oxomo is 6300 TY

Zacatzontli is 7000 TY

Miquiztlitecuhtli completes one orbit in 30,000 years!


2) There is a constant Terran military presence on Camaxtli colony which monitors activities around the outer system. Satellites in orbit around Ehecatl and Tloxipeuhca are used for both research and surveillance. An advance base populated by scientists on Vitztlanpaehecatl, Tloxipeuhca's Phobos-sized tertiary, also keeps watch on things, occasionally going down to the surface to do research.

I shouldn't have to say that Ammonia is quite poisonous :D

If you drank it you'd die from the Ammonia, and you'd burst into flames from the dissolved Alkali metals
 
Last edited:
Now we know that Atlacamani's year is a whopping 64 Terran years! Doesn't that get some time to get used to, approximately 16 years of summer, or, for that sake, winter? Especially as you said that some Terrans are convinced of staying on Atlacamani...

Or do maybe Atlacamanians call a different period a "year", and if so, how is a "year" defined? Or might this division be nonexistent?

How do the Terrans on Atlacamani, and the local Atlacamanians, do this with months, and payments and so on? Is a payment really only to be paid in 5,33333.... TY if it is payable in "one Atlacamanian month", or how do you deal with this? The same with wages: Do you get your wage every 5,333 years only?
 
Or do the people just use vast calendars with 768 months, and, at the end of the Atlacamani year, just pay e.g. a whopping insurance premium of approx. 64 times the Terran yearly rate?

Can you grow food on Atlacamani in it's winter, too (I think you can, as you specified that it also had a polar, temperate, tropical,... climate zone)? Where would you otherwise get food in the 16 years of winter (especially since the nearest source, Chalchiutotolin, is lethal to you as it is made of Teflon and filled with HF!)?
 

Dorozhand

Banned
Now we know that Atlacamani's year is a whopping 64 Terran years! Doesn't that get some time to get used to, approximately 16 years of summer, or, for that sake, winter? Especially as you said that some Terrans are convinced of staying on Atlacamani...

Or do maybe Atlacamanians call a different period a "year", and if so, how is a "year" defined? Or might this division be nonexistent?

How do the Terrans on Atlacamani, and the local Atlacamanians, do this with months, and payments and so on? Is a payment really only to be paid in 5,33333.... TY if it is payable in "one Atlacamanian month", or how do you deal with this? The same with wages: Do you get your wage every 5,333 years only?
There is one more complicating factor. Atlacamani's axial tilt also goes through a large gyroscopic precession once every 13 Terran Years, due to the impact which created Chicomecoatl. It isn't certain, but it's believed by some that the impactor may actually have been a rogue planet flung from a nearby system, as it seems to have come in at nearly a 45 degree angle (which is also the angle of Chicomecoatl's orbit). This means that the seasons go through a 13 TY main cycle, while also going through the 64 TY yearly cycle.

Atlacamani's 13 year calendar goes through all of the seasons, and is divided into 13 sections of approximately TY length (with leap days and the like to correct for the small discrepancy) which in turn are divided into 13 "months" around which you'd (unless you're a farmer) really base your time. The larger calendar also maps out the precession as it relates to the turning of the years and how the seasons metamorphose through this period.
 
Last edited:
What exactly is the effect of that gyroscopic precession? It is spring for what, 13 TY (= 1 Atlacamani calendar year), then summer, autumn, and winter? Or is the season length variable, or are there a few short "seasons" in between, or what?

However, a system of 13 (near-Terran) months in 13 Atlacamani months in 13 TY is very interesting! So, you would per "calendar year" recieve 13x13x13= 2197 payments if residing on Atlacamani.

What is the exact length of this calendar year, so that we can calculate the exact length of an Atlacamani month?

Sorry... I am not an astronomic expert, and thus I don't know much about effects of (gyroscopic) turning patterns on planetary seasons.

EDIT: Beautiful mappings of molecules, Dorozhand, and really informative they are!
 
Last edited by a moderator:

Dorozhand

Banned
What exactly is the effect of that gyroscopic precession? It is spring for what, 13 TY, then summer, autumn, and winter? Or is the season length variable, or are there a few short "seasons" in between, or what?

Sorry... I am not an astronomic expert, and thus I don't know much about effects of turning patterns on planetary seasons.

EDIT: Beautiful mappings of molecules, Dorozhand, and really informative!
The axial tilt goes through revolutions. It stays at the same angle, but through a 13 TY cycle moves in a circle so that the hemispheres swap directions (and therefore winter/summer) every 6.5 TY. In the temperate zones, there are rough analogues of the four familiar seasons.
-In winter, snow falls and plants go into dormancy
-In spring, the snow melts and plants regrow their foliage
-In summer, plants release fruit and most fungi release spores
-In autumn, the leaves of the plants turn yellow, green, blue, and violet, before falling to the earth and providing detritus for the growing fungi

In the tropics, there is a wet season, where the wet-weather plants thrive. Towards the end of the season, they release fruit, and seeds go into the ground and lay dormant.
-Then there is a dry season, during which wet weather plants suffer a massive dieback and dry weather flora take over. Cactus-like organisms as well as bulbous balls of orange photosynthesizing flesh bloom and cover the dry landscape. Before this season ends, they release fruit and/or put down deep roots for asexual reproduction. The seeds and roots lay dormant.
-When the rains come again, the dry weather plants die off and are washed into the inland seas by torrential floods and refilled rivers, where they fertilize the sea and allow for an algal and fungal bloom

In the steppe, there is a cold-dry season where the ground is covered in frost, the grasses die, and the sky throws down freezing rain and hail. This is followed by a warm-wet season where grasses and small trees bloom. After that is a third, cold-wet season where grasses grow extremely tall, cold rains fall as the trees fan out their leaves to gain as much sunlight as possible. Then the cold-dry season begins again.

In the tundra, there is a season of relative warmth where small shrubs manage to grow above the permafrost, followed by a very harsh winter.

This happens over a period of 13 years.

It is also of note that the true orbital year of 64 TY also affects the seasons, which go through subtle changes in length and intensity as the perihelion and aphelion are reached.
 
Top