41 Cygnus c, nicknamed Helen after the mythical daughter of Zeus and Leda, is a terrestrial planet located in the 41 Cygnus planetary system. It is the first planet orbiting from its star, and the second to be discovered in the system. It orbits 41 Cygnus at a periapsis (nearest distance) of about 158,400,000 km (99,046,600 mi), and an apoapsis (farthest distance) of about 165,600,000 km (102,899,000 mi). Helen has no known satellites.

Geological and Climatic Features[]

Helen has a mean radius of 7946 km (4937 mi), approximately 20% larger than Earth, with an equatorial surface gravity 1.3x greater. It is a very geologically active planet, with a plate tectonics system and many volcanic craters. Because of its increased geological activity, the landscape of Helen transforms and renews itself often, leaving it with many long mountain ranges, but few to rival Earth’s in height. The planet’s high gravity and dense atmosphere also play a role in keeping its mountains low. The atmospheric pressure at sea level on Helen is about 14x that of Earth. While this is little compared to the crushing extremes at the surface of a planet like Venus, this still has noticeable effects on Helen’s climate. Because the atmosphere consists of 19% carbon dioxide, this couples with the extreme density to produce a severe greenhouse effect that leaves the average surface temperature of Helen at a sweltering 135°F (57°C). The greenhouse effect also makes the surface temperature of the planet almost uniform throughout, even at the poles. Thus, Helen has no polar ice caps, and truly, no ice anywhere on its surface.

In addition, almost all the oceans on Helen have long since dried up, leaving the atmosphere with a concentration of water vapor four times higher than that of Earth’s. The rest, about 52% of the water on Helen, is locked inside underground aquifers just below the surface. The only body of water on the planet larger than a small lake is the so-called "Last Ocean", about the size of South America. The result of Helen's large concentration of water vapor coupled with the extreme heat is that the planet has many clouds, but receives little rainfall. In fact, with the exception of the lush marsh-forests surrounding the Last Ocean, rain falls somewhere on Helen only once every month or so. Considering the size of the planet, this means that some places can go without any rain for decades. However, oftentimes rain evaporates before it even reaches the surface of the planet, meaning that it actually rains more frequently than what is experienced on the ground. When it does rain on the surface of the planet, it can be very heavy indeed, and is occasionally accompanied by intense thunderstorms. These rainstorms can last for up to four days straight, traveling miles as they precipitate. Because of the extreme lack of water on Helen, 55% of the planet's surface is stony desert land, much of which does not receive rainfall for centuries, and is completely uninhabitable save for a small number of extremophile species.

The planet has an orbital period of 423 days, but its very slight axial tilt, along with the aforementioned homogenizing effect of its dense atmosphere, does not allow for much variation between seasons. Thus, the hemispheres remain exactly the same all year-round. In addition, a day on Helen is a little more than 19 hours.


This is a basic summary of the type of lifeforms found on Helen. Like Earth, 41 Cygnus c supports a wide variety of life, much of which would seem odd and improbable on Earth. To categorize life on Helen, a taxonomic system similar to that of Earth’s organisms is used, with kingdoms and genera and species and so forth. Organisms on Helen are classified according to features that are thought to have played an important part in the evolution of life on the planet.


Although the system of taxonomy is still being fine-tuned, to begin with, there are four domains into which life on Helen is classified: Microzoa, Xenofungi, and Pseudocardia. Microzoa is an informal umbrella domain for all of the unicellular and some simple multicellular organisms on Helen. The unifying characteristic seems to be a lack of cell specialization usually associated with prokaryotes on Earth. As the Microzoa domain is still extremely understudied, new discoveries will probably be made that will shed light on the classification of these organisms.

Xenofungi, or "alien fungi", is of course not true fungi like that on Earth, but multicellular fungus-like organisms. They are all chemotropic and most live in extreme environments, such as deep underground, in the hottest deserts of Helen, or at the bottom of the ocean. They all reproduce asexually, but surprisingly, there appears to be a staggering range of biological diversity in these life forms. Xenofungi share many more similarities with organisms in the following domain than those in Microzoa, leading many biologists to speculate that the group split from a common ancestor of all Xenofungi, plants, and animals on Helen, a creature that may have resembled an amoeba or protist.

Finally, there are the Pseudocardia, whose name means "pseudo-heart", so-called because of the existence of multiple heart-like organs within these organisms used to pump fluids (although in some types of plants, this organ has been lost or reduced in function). The common ancestor of all organisms in this domain was probably a highly advanced xenofungi-like organism with a rudimentary body plan containing porous channels for pumping fluids; it most likely lived in shallow waters. This domain includes the kingdoms Helenoplantae and Helenozoa, consisting of plant-like and animal-like organisms, respectively. There are some distinguishing features of both kingdoms that draw contrast to the history of life on earth.


For starters, plants on Helen were most likely originally chemosynthetic, surviving off the presence of sulfur and hydrogen vents in the profundal zone. As they gradually propagated upwards, they became increasingly more dependent on photosynthesis. As Earth’s plants are green due to the presence of chlorophyll, Helen's plants are a distinctive yellowish-orange for reasons of efficiency; though more unusual colors are noted in extreme desert and polar flora. The majority of plants have no stems or leaves to speak of, but have enormous and expansive root systems. Plants in the lush vegetative regions near the only source of fresh water compete with one another for limited nutrients in the soil, while plants in the harsh deserts must stretch their roots deep into the ground for water from the subterranean aquifers. Some plants do have leaf-like extensions, but these are usually fairly large structures and contain roots, reproductive organs, and vast vascular systems of their own.


Helenozoa is a kingdom analogous to animals. They are multicellular heterotrophs just like animals, and have many similar features to creatures on Earth, although some are quite unusual. The taxonomy of Helenozoa is still undergoing study and development, though one feature known to have influenced the evolution of animals on Helen is the development of a skeleton. In the same way that animals on Earth can be divided into the groups of invertebrate and vertebrate, Helen’s animal life can be divided into those with exoskeletons, and those with phleboskeletons. A phleboskeleton is a joint cardiovascular-skeletal system consisting of multiple small hearts at major junctions of vessels. These vessels are covered in rigid, bone-like material on the outside, but contain an inner layer of muscle that surrounds the oxygen-transporting fluid. Smaller tubes lead off from main vessels, and smaller-still capillaries (not surrounded by bone) emerge from holes in these arteries. This skeleton, though seemingly rigid and fixed, is actually quite flexible due to the role of the some hearts as “joint areas” where different vessels can pull and change position. The result is a creature with a sturdy skeleton, but a limb flexibility unseen in earth’s creatures. Creatures without this inner skeleton instead have a tough exoskeleton similar to that of insects and crustaceans, though unlike in arthropods, this skeleton does not cover the entire creature’s body, only parts vital to movement. Many creatures also lack skin, and simply have an outer layer of muscle which works similarly.

Helen’s creatures lack the smell- and taste-sensing organs of Earth’s animals, being able only to detect acidity/alkalinity. However, they also have a more advanced system of vision, allowing them to see not only within the regular color spectrum, but also infrared and ultraviolet. These visual organs are located not proper “eyes”, but bulging “optical patches” containing sight receptors. Hearing also seems to have evolved independently on Helen multiple times. Most creatures with hearing possess simple ears on their limbs or head.

An interesting feature of Helen’s animal life is the existence of three different genders: "male", "female", and "hermaphrodite". These genders are not genetically-determined, and can actually be changed throughout an individual’s life. The male gender refers to the phase in a creature’s life when it produces male sex cells (sperm) that are released to fertilize ova. Female refers to the phase when the creature produces only egg cells to be fertilized. Hermaphrodite refers to the phase when creatures produce both types of cells. When two hermaphroditic individuals breed, they impregnate each other. All three sexes can mate with one another at any given time. Creatures are born hermaphrodites, and sometimes remain as such throughout their lives, but most species can and frequently do change their sex—though the purpose of this mechanism is still unknown. There also seems to be no other behavioral or morphological differences between the three sexes.



  • Aeronautilus
  • Rain Scourge
  • Rootcrawler
  • Springheel
  • Stagwrist


  • Driftree
  • Giant Goblet Plant
  • Mazeweed