Report on Aqua (“Alpha”) and Its System: Astrophysics, Geophysics and Biosphere

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European Science Committee, in cooperation with the International Astronomical Union, the Woods Hole Oceanographic Institution and NASA.

Executive summary: The IAU and ESC recommend naming the system Ignis and the currently inhabited planet Aqua. The system is described; it consists of three planets and an asteroid belt. The geology of Aqua is found to be very active. Simulations of Aqua climate suggests that it undergoes periodic changes due to the eccentric orbit between a relatively short, stormy worldwide ‘summer’ and a longer more stable worldwide ‘winter’. The biochemistry of Aquan life is very different from terrestrial, but some nutrient exchange can occur, giving rise to ecological concerns and farm applications.

Notes on naming conventions

The IAU nomenclature meeting explored several naming schemes. One proposal suggested naming planets and moons after their closest equivalents in the solar system, but switching between the Greek and Roman pantheons (e.g. naming the gas giant Zeus in analogy with Jupiter). This was felt to be unwieldy. Finding another culturally neutral pantheon proved sensitive; both the Nordic, Japanese and Hittite pantheons were discussed. One proposal suggested naming the bodies after nations not saved in the evacuation. While creative and possibly a fitting memorial, it was noted that the number of potential names was far larger than the number of bodies. Similarly the idea of naming the bodies after gods or historical persons giving sanctuary to refugees was found to be too controversial.

In the end the naming system settled on the classical four elements. Given the extreme oceanic coverage of the third planet, the barren deserts of the second and the extensive atmosphere of the first, it was natural to assign them to water, earth and air. The sun would hence be fire. In keeping with the Latin nomenclature of the Solar system the Latin elemental names were used. The slight problem of using the name Terra for the third planet was considered to be minor; the risk of confusing it with Sol III is low. Moons would be assigned to deities linked to the element. Members of the asteroid belt will be named according to the same rules as asteroids in the Solar main belt.

It is hence IAU’s decision to name the system the Ignis system. Ignis I is Aer, Ignis II Terra and Ignis III Aqua. Ignis Iia is Redarator (roman god of ploughing) and Ignis IIIa is Salacia (Goddess of salt) while Ignis IIIb Juterna (Goddess of hot springs).

System

Central body: Ignis

Mass: 1.47 solar masses

Luminosity: 6.1100

Radius: 1.4 solar radius

Spectral class: F2V

Age: 2.9 billion years

Ignis is relatively old for a F2 star. It has already begun to increase in luminosity markedly, and will within the next few hundred million years leave the main sequence and become a red giant.

Asteroids

Ignis is orbited by a dense asteroid belt with mean distance 0.41 AU. The asteroids appear to be mainly heavy silicate (average density 6000 kg/m³). The total mass is approximately 0.3 earth masses. Major objects are tidally locked to the star.

Ignis I: Aer

Mean distance: 0.5927 AU

Year: 0.37 Earth years

Radius: 20,100 km

Density: 0.25 Earth densities

Mass: 7.81 Earth masses

Surface gravity: 0.78

Escape velocity: 18 km/s

Eccentricity: 0.035

Axial tilt: 0 degrees

Rotational period: 0.37 Earth years

Surface temperature: 247 C

Magnetic field: 3.0 Gauss

Albedo: 0.38

Aer is a small gas giant, smaller than Uranus in the solar system in terms of size and mass. The atmosphere is a dense mixture of nitrogen, carbon dioxide and water vapour, deep blue in colour due to atmospheric scattering. White clouds of ice and sulphur compounds give it a striped appearance. Due to the proximity of Ignis it has become tidally locked, likely losing any of its moons in the process. The global circulation involves massive upwellings of gas on the hot side, which produce very strong winds towards the cold side where the cooling atmosphere sinks.

Ignis II: Terra

Mean distance: 1.0483 AU

Year: 0.88 Earth years

Radius: 2,900 km

Density: 0.4 Earth densities

Mass: 0.03 Earth masses

Surface gravity: 0.18

Escape velocity: 3.3 km/s

Eccentricity: 0.18

Axial tilt: 12 degrees

Rotational period: 18 Earth years

Surface temperature: 118 C

Magnetic field: 0.0 Gauss

Albedo: 0.30

A Mars-like world with a thin atmosphere and extensive cratering. Terra is tectonically dead and appears to lack metal core.

Terra is orbited by a small moon, Redarator, a 23 kilometer silicate asteroid in a very close (5800 km) and highly inclined (66 degrees) orbit.

The extremely slow (sideral) rotation is notable. It appears likely that Terra has undergone a severe relatively recent encounter with another body. A possible cause could be the loss of the moons of Aer as it tidally locked: one of the moons passed close to Terra or impacted it. This can also explain the eccentricity of the orbit and perhaps the inclined orbit of Redarator. Several geological features could be major impact basins.

Ignis III: Aqua

Mean distance: 2.19 AU

Year: 2.68 Earth years (1,769 Aqua days)

Radius: 6621 km

Density: 1.02 Earth densities

Mass: 1.14 Earth masses

Surface gravity: 1.05

Escape velocity: 12.03 km/s

Eccentricity: 0.0250

Axial tilt: 5 degrees

Rotational period: 0.7737 Earth days (18h34m4s)

Solar day: 0. 5531 Earth days (18h33m11s)

Surface temperature: 118 C

Magnetic field: 1.2 Gauss (inclined 27 degrees)

Albedo: 0.33

Hydrosphere: 88%

Atmosphere: nitrogen 70%, oxygen 27%, argon 2.7%, carbon dioxide, inert gases, methane 0.3%

Pressure: 0.912 atmospheres

Mean surface temperature: 28.4 degrees

Greenhouse effect: 31 degrees

Atmospheric scale height: 8.6085 kilometres

Aqua is a terrestrial planet, very similar to the Earth. It has a iron-nickel core surrounded by a mantle of terrestrial composition. The surface is mostly covered with ocean with occasional island chains and minor continents/major islands.

The planet is strongly geologically active and appears to exhibit “platelet dynamics”. Rather than large continental plates the crust is far thinner and more dynamic, producing a far greater number of earthquakes, volcanoes and geological hotspots. It should be noted that all surveyed land on Aqua is volcanic in origin and geologically active.

The planet has a magnetic field twice as strong as Earth. Given the higher solar activity of Ignis this is fortunate as it blocks much of the solar wind in extensive van Allen belts. This also results in the extensive auroras seen across the Polar Regions. The atmosphere also has a thick ozone layer; the average UV-B radiation on the ground is lower than on Earth. However, the higher incidence of ‘soft’ UV-A is higher and will cause skin ageing, wrinkles, damage plastics and paint. It is hence recommended that people wear hats, sunscreens or other protective measurements to avoid sunburn. The effect on terrestrial plants is uncertain; it is likely that it will inhibit the growth of some plants under some conditions and stimulate others.

The fast rotation induces a strongly east-west weather pattern. The Coriolis force redirects air into bands rather than allowing it to flow towards the poles from the equator. This, together with the low axial tilt, tends to increase equatorial and decrease polar temperatures. However, the large ocean surface acts as a moderating force. Several powerful oceanic currents transport warmer water towards the poles. Simulations suggest that the atmospheric bands are likely not stable across the year, and can oscillate or temporarily break up into extended weather systems. Given the hot equatorial surface water tropical storms are common and propagate for long distances, especially in the convergence zones.

The low axial tilt makes the effect of summer and winter small, but the eccentricity of the orbit produces notable temperature differences. During the perihelion the average polar temperature goes up to –3.41 C while the equatorial region reaches 36.8 C. During the aphelion the polar temperatures drop to –17.8 C and the equator to 26.2 C.

The poles do not have any permanent ice caps, but glaciers exist on some polar islands and produce drifting icebergs. During the aphelion periods ice covers the poles but breaks up when southerly weather systems intrude.

Given the smallness of the moons it is likely that the inclination of the rotation axis changes over time. This has less climate effects than it would have on Earth, since most of the surface is homogeneous ocean.

Aqua was likely a glacial world for most of its history, similar to the Precambrian “snowball Earth”. Life may have persisted in geothermally heated supersaline environments under the ice sheets, occasionally emerging on the surface during periods of strong volcanic activity releasing greenhouse gasses. Relatively recently (last few hundred million years) the increased solar input caused the ice sheets to melt and enabled life to develop complexity. It should be noted that while Aqua will become uninhabitable in the relatively close geological future (hundreds of millions of years), it is no cause for concern at present. The eccentric orbit combined with high degree of volcanism makes the greenhouse effect variable. At present they combine to keep the climate stable, but as the planet warms up fluctuations are likely to grow and may cause climate collapse. This suggests that human residents should establish strict greenhouse gas controls in order not to worsen the situation.

Moons

Salacia

Average distance: 8 planetary radii (52,968 kilometres)

Radius: 311 kilometres

Density: 0.6 Earth densities

Mass: 6.9498e-005 Earth masses

Surface gravity: 0.0292 G

Period: 1.2714 days (1.6434 Aqua days)

Eccentricity: 0.33

Juterna

Average distance: 16 planetary radii (105,936 kilometres)

Radius: 820 kilometres

Density: 1.0 Earth densities

Mass: 0.0021 Earth masses

Surface gravity: 0.1285

Period: 3.5961 days (4.6482 Aqua days)

Eccentricity: 0.015

Salacia and Juterna are small, asteroid-like moons. Salacia appears to be recently captured and has a notably eccentric orbit. Both are yellowish, apparently from iron oxide compounds on their surface. Neither are large enough to cause significant tides.

Aquan Biology

Aquan biochemistry is carbon-based but notably different from terrestrial biochemistry. While many building blocks are common, such as amino acids and sugars, often the chirality and modifications of the molecules are entirely different. Aquan life uses both L- and D-amino acids, as well as sulphurated and chlorinated carbohydrates that have no similarities to terrestrial biochemistry. The genetic code does not use nucleic acids; its exact nature remains to be discovered.

Aquan organisms can be used as sources for nutrients for terrestrial organisms, but the potential for allergies in mammals remains worrisome. It is probably safe and useful to mulch aquan plants, and with some effort it would likely be possible to extract nutrients chemically from plants and animals.

Aquan lifeforms appear to have evolved for a long time in supersaline environments, and show marked salt and heat tolerance. Most land-living organisms are covered with a chitin-like exoskeleton which also contains salt deposits which are a by-product of metabolism. They are often remarkably heat tolerant. At least two species are already known that lay eggs that wait to hatch until a fire or volcanic eruption occurs. The hot springs of the planet are rich ecosystems both on land and in water, with diversity not unlike terrestrial coral reefs.

The risks to terrestrial and aquan ecosystems are great. The rapid introduction of large areas of terrestrial land with insects, bacteria and fungi (as well as sea organisms near the transport of ships) have already resulted in contamination. It is unknown how well different species can survive within the other ecosystem. In experiments insects did not survive on a pure aquan diet, but did thrive with some terrestrial nutrient supplementation. Terrestrial bacteria can break down aquan biomass, while aquan microorganisms appear less effective at breaking down terrestrial biomass. They appear to have special problems with breaking down terrestrial organic phosphates, while terrestrial organisms largely ignore the inedible sulphurate carbohydrates. However, if chlorinated carboxylic acids are released at some step then toxic risks become serious. Hence the main concern should be that terrestrial saprophytes do not invade aquan ecosystems.

So far mostly nearby land has been surveyed. Land life appears about as diverse as on Earth and will take years to fully survey. Many roles in the ecosystem appears to have analogues: small, ground covering autotrophs similar to terrestrial grasses and herbs, larger autotrophs similar to bushes and trees, herbivores grazing the plants and predators living on them. The bluish colour of most plants is not due to pigmentation, but rather a slightly reflective protective covering (against excessive sunlight, fire and possibly herbivores) reflecting the sky; the chlorophyll analogue is a mild yellow.

Aqua appears to have a wide range of species based on the same four-legged crustacean-like body plan, ranging from submillimeter “mites” (terminology yet to be determined) to the common grazing “walking tables”. The “walking tables” form herds and graze on the covering vegetation as well as the “cheese covers”. The “cheese covers” appears to be protective structures built by smaller worm-like colonial creatures, perhaps akin to terrestrial leaf-cutter ants. There are many flying “mites”, which in turn feed the “feather dusters”, flying insectivores with snakelike bodies covered with long feelers likely to act as traps for mites. None of the animals discovered so far pose any known threat to humans except possibly being trampled by the “walking tables”. Sea life is even less understood, but appears to be very rich.