Backstory
The basis of the default setting is to consider a realistic path to humanity’s expansion into the wider cosmos. I will expand upon this at a later date but it will likely include the following:
- Complete colonisation of the solar system
- Automated interstellar probes investigating alien biospheres
- Human colonisation of nearby star systems
- The divergence of humanity and its technology into various branches
Biospheres
The following fictional exoplanets each describe a potential idea I have had, inspired by scientific literature. For each of them I have done a variable amount of research into their viability though the basic idea is present. My intent is to write something about each one over the period of the blog.
Achlys
Can an ecosystem form using hydrogen instead of oxygen?
On a moon larger than Earth that orbits a super-Jupiter exists an ecosystem with unusual biochemistry. Strange life swims in ammonia oceans while iron clad bugs crawl the volcanic landscape and perpetually soaring creatures glide in the haze above. To see through the thick atmosphere sophisticated magnetoreception is common, aided by the gas giant’s strong and varying magnetic field.
- Can graphene bilayers be the membrane mimetic materials?
- Photosynthesis in Hydrogen-Dominated Atmospheres
- A Volcanic Hydrogen Habitable Zone
Anemos
What does life need to do to survive on a planet with a highly eccentric orbit?
In an extremely eccentric orbit this planet experiences massive changes in illumination through the year. During “summer” the planet is close to its star and experiences extremely hot conditions. Autumn brings more survivable temperatures as the planet recedes from the sun. Temperatures continue to drop as the long winter arrives and all life stops until spring when the planet again swings towards the sun.
- Habitability and Water Loss Limits on Eccentric Planets Orbiting Main Sequence Stars
- Habitability of planets on eccentric orbits: Limits of the mean flux approximation
- Photosynthetic Potential of Planets in 3:2 Spin Orbit Resonances
Chiaro
Can a world have longer days than nights without being tidally locked?
A Mars sized moon orbits a gas giant which orbits an F-class binary. The light from the two stars reflects from water clouds in the gas giant producing a day-night pattern very different to Earth. The abundant blue light allows lush phototrophic life to grow but the harsh UV levels cause problems for other life. A giant exoskeletal insect-like clade dominates the day and a soft skinned amphibian-like clade the night.
- Energy Budgets for Terrestrial Extrasolar Planets
- Habitability around F-type Stars
- Photosynthesis on Exoplanets and Exomoons from Reflected Light
Elais
On distant worlds can life thrive in frigid seas of liquid hydrocarbons?
A Mars sized planet orbits a distant red star. Upon on its frigid surface lie lakes of liquid hydrocarbons. Underneath lie hidden oceans of water tainted with ammonia. A bounty of organic haze is produced in the upper atmosphere during solar flares. This rains from above like manna from heaven while phototrophs survive on the infrared light that penetrates the haze.
- Solubility of Polyethers in Hydrocarbons at Low Temperatures. A Model for Potential Genetic Backbones on Warm Titans
- Titan as the Abode of Life
- Titan: Earth-like on the Outside, Ocean World on the Inside
Epimetheus
In what environment would lighter-than-air gasbag life thrive?
A massive super-Earth with a thick carbon dioxide atmosphere orbits a distance F-class star. Frequent asteroid impacts from have slowed its rotation and formed two moons. The continuing supply of dust from above seeds the clouds with nutrients. Volcanic activity and sea spray do the same from below. Due to the scarcity of solid land life moved into the sky to follow day light as it slowly moves around the world.
- The impact of CO2 ice clouds on the outer boundary of the habitable zone
- Outgassing on stagnant-lid super-Earths
- Possibilities for an Aerial Biosphere in Temperate Sub Neptune-Sized Exoplanet Atmospheres
Ginnungagap
Can life exist in the void of space?
A massive and highly eccentric gas giant orbits its host star like a comet, moving between the heat of the sun and the distant icy void. Around this gas giant is a complex system of rings and moons of various sizes. As the planet orbits, ice in the rings sublimates to vapour and refreezes back into ice, continually replenished by emissions from the frozen moons. While simple life began on a moon, it has now moved to colonise the rings and take advantage of the orbital cycle.
- Atmospheric Evolution on Low-gravity Waterworlds
- Cronomoons: origin, dynamics, and light-curve features of ringed exomoons
- What it would be like to live on a comet
Jormungandr
How much life can an almost completely ice covered world support?
A frozen world slightly smaller than Earth exists with only an equatorial belt of open ocean that moves with the seasons like a serpent encircling the world. Light from a star slightly warmer than the Sun penetrates the thin ice to support algae living on the icy ceiling. On the sea bed life survives on mana from above and chemicals from below. Under the thick ice, life extracts energy from thermal, ionic and osmotic gradients to survive. Scattered volcanic islands penetrate the ice and provide oases for the rare terrestrial life.
- The Jormungand global climate state and implications for Neoproterozoic glaciations
- Sea ice, extremophiles and life on extra-terrestrial ocean worlds
- Strategy for Modeling Putative Multilevel Ecosystems on Europa
Khthonia
How would life evolve on a world exposed to a wider spread of wavelengths of light?
A planet slightly more massive than Earth orbits a close twin red dwarf binary. Khthonia formed as a mini-neptune but over time flares from the red dwarfs have converted it into a tidally locked Earth-like habitable evaporated core. Not only has life adapted to survive the frequent flares, it also harvests light across the entire spectrum from ultraviolet flares to the short wave infrared.
- Circumbinary Habitability Niches
- Habitability Properties of Circumbinary Planets
- Habitable Evaporated Cores: Transforming Mini-Neptunes into Super-Earths in the Habitable Zones of M Dwarfs
Maelstrom
Can life survive in a purely aerial environment?
Seeded with simple life from elsewhere, this mini-Neptune became a home for life that remains permanently floating in the air. It ascends to take advantage of clearer skies and more abundant sunlight. As it grows it becomes heavier and sinks towards the core. Before reaching the infernal depths below it must reproduce to begin the cycle anew.
- Atmospheric Habitable Zones in Y Dwarf Atmospheres
- Possibilities for an Aerial Biosphere in Temperate Sub Neptune-Sized Exoplanet Atmospheres
- The Venusian Lower Atmosphere Haze as a Depot for Desiccated Microbial Life: A Proposed Life Cycle for Persistence of the Venusian Aerial Biosphere
Tezca
Where could silicon-based life be found?
Around a dying ember of a cooling white dwarf orbits a planet rich in carbon formed from the debris of a supernova. All its water has been boiled away leaving hydrocarbon and hydrogen cyanide oceans. Among silicon carbide rocks a dark mirror of Earth life has evolved that is based on silicon not carbon. Silicon crystal wings are raised to capture the perpetual sunlight and power the ecosystem.
- Extrasolar Carbon Planets
- Habitable Planets Around White and Brown Dwarfs: The Perils of a Cooling Primary
- On the Potential of Silicon as a Building Block for Life
Xeros
Can a barren desert planet produce giant sand worms?
A second generation planet formed around a white dwarf / red dwarf binary from the debris of the white dwarf’s birth. Xeros was baked almost dry while the white dwarf cooled and what remained became a cold volcanic desert. Most of the planet is barren but life stubbornly thrives in a few footholds. From the salty lakes on the light side to the temporary buffer between ice and lava on the dark side. In scattered locations, plentiful volcanic gas bubbles from beneath the sands to produce a fluidised mixture through which larger organisms can move⦠and hunt.
- Second generation planets
- Swimming in granular media
- Titania may produce abiotic oxygen atmospheres on habitable exoplanets
Yomi
What sort of life could exist on a planet orbiting a pulsar?
A dark planet with an atmosphere vastly thicker than Earth’s orbits a pulsar. It is warmed by the extreme x-rays and solar wind produced by the pulsar. The surface in the stygian gloom below is habitable in a way, though the strange life that swims through supercritical carbon dioxide is not at all like that on Earth.