Serenity Shores
A super-Earth 63% larger than our planet and with 3.29 times its mass, orbiting on the outer edge of the habitable zone of a G-type star, similar to our sun. It is a massive world, with strong geological activity and greater gravity that has allowed it to maintain a dense atmosphere, about 10 bars of surface pressure rich in nitrogen, methane, and carbon dioxide. The methane in its atmosphere, interacting with the UV radiation from its star, generates a dense orange photochemical smog in the upper atmosphere, which absorbs most of the light, creating a much darker and colder surface than expected, around -80 degrees Celsius. This has caused most of the oceans to freeze, forming an ice crust about 8 km thick, dotted with mountain peaks due to tectonic and volcanic activity. Beneath the surface, along the deepest areas and the edges of different tectonic plates, lies a subglacial ocean where the planet’s internal heat, or directly the action of volcanoes, magma, and hydrothermal vents, prevents it from freezing.
Planet summary
The following table summarizes the characteristics of this planet, comparing its mass, radius, and gravity with that of the Earth (Me, Re and g). A similar table can be found below, comparing the characteristics of the star’s mass, radius, and light with our Sun (Ms, Rs and Ls).
|
Type
|
Mass
|
Radious
|
Density
|
Gravity
|
|---|---|---|---|---|
|
Superearth
|
5,92 (Me)
|
1,63 (Re)
|
7,55 (g/cm3)
|
2,23 (g)
|
|
Type
|
Mass
|
Radious
|
Light
|
Temp.
|
Year
|
|---|---|---|---|---|---|
|
G
|
1,037 (Ms)
|
1,11 (Rs)
|
120% (Ls)
|
5757(K)
|
384,8(days)
|
Atmosphere and surface features
In the upper atmosphere, the photochemical smog gradually creates organic compounds of different complexity and weight that gradually deposit on the surface or are carried by precipitation. On the high plateaus and mountains, thanks to the high atmospheric pressure and low temperatures, compounds like methane and ethane can precipitate in liquid form, creating rivers and lakes.
There, the organic compounds that snow down from the upper atmosphere are dissolved and carried to lower and less cold areas where methane and ethane evaporate, leaving behind a viscous substance similar to oil, rich in organic compounds that slowly moves, filling depressions in the ice crust.
Life around glacial seas
In some areas, the ice crust is melted by the subglacial ocean, creating a depressed region with a warm sea or lake at its center. Here, water rich in minerals and volcanic gases comes into contact with an environment laden with organic materials.
The warm water diffuses radially, cools, and sinks at the edges of these seas, where hydrocarbons accumulate in floating masses near the coast. Huge dark fungi grow on these floating masses and sometimes on the icy coast covered by hydrocarbons, with deep roots reaching down to the mineral-rich water in the depths.
Bacteria that feed on methane and hydrocarbons dominate this environment. Creatures similar to crabs and orange worms inhabit these areas. Occasionally, over the frozen surface of lakes, chemosynthetic orange and yellow bacteria grow through cracks, forming a high-contrast web pattern.
Life in geisers fields
In other areas, hot spots in the crust create pockets of hot water hyper-saturated with minerals and volcanic gasses, which force their way through the crust and explode violently in geysers. Over time, these openings widen as the surrounding ice melts, but a layer of minerals begins to grow, precipitating on the surface, stabilizing the conduit.
On the surface, these minerals also precipitate, forming layers several meters thick, supporting thermal lakes and rivers above an ice crust. Sulfur bacteria live especially in hot areas, near geysers and thermal springs, forming a mat several centimeters thick together with colonies of multicolored tube worms.
Organisms similar to giant lichens grow on coldest areas, over mineral concretions on the coasts, that obtain minerals from the rocky substrate and are symbiotic with bacteria that consume hydrocarbons. Creatures similar to centipedes roam this area, eating lichens
An environment like Serenity Shores could exist on the super earth exoplanet Kepler-452b, located about 1,400 light-years away from Earth in the constellation Cygnus. It orbits a G2-type star, similar to our Sun, is situated in the habitable zone, and the discovery was announced by NASA in 2015, using data from the Kepler Space Telescope. In our solar system, the surface environment and atmosphere could remember Titan, the biggest moon around Saturn.
More information about Kepler-452b: