STARTING PARAMETERS

PAART'S INITIAL PARAMETERS REFER TO WHAT IT WAS LIKE AT DAWN OF COMPLEX MULTICELLULAR LIFE

MORE SPECIFICALLY AT ~3800 PMA
PMA = Paart's Mean Age in millions of years

PHYSICAL PARAMETERS

Mass
4,76 septillion kg 

(0,798x Earth's)

 

Diameter

11.786 km 

(0,9249x Earth's)

Avg. Density 
5,56g/cm³ | comparable to that of Earth

(1,01x Earth's)

 

Surface Gravity
9,15m/s²
(0,93x Earth's)

 

Mean Composition
O 38%; Si 20% ; Bi 14%; Al 9%; Fe 8%; Ti 5%; Ca 3%; 2% K, 0,5% Zn, Na, Mg and other trace elements ~0,5%.

Orbital Distance

1,11 AU | e ≃ 0,018

(~166,5 million km)

 

Orbital Period

442 Earth days

Internal Structure

Core Mass: 17,51% (0,1398 Earth-masses)

Core Radius: 2.809,4 km

ATMOSPHERIC & CLIMATIC PARAMETERS

Bond Albedo

~0,362 | 0,192 surface

Top of Atmosphere Insolation

60,25% that of Earth's

(~825,4 W/m²)

Mean Atmospheric Parameters

Atmospheric Mass: 2,52x that of Earth's

Starting Composition:

N²        83,0%     O²        10,0%

CO²     5,00%     CH⁴      0,70%

NH³     0,20%      H²O     0,24%

SO²     0,0095%    Argon, Xenon, and other trace gases 0,85%

Molecular Weight: 29,25 g/mol

Density under STP: 3,45 kg/m³

Surface Pressure: 278,4 kPa (2,75 bar)

Air Density at Sealevel: 3,5 kg/m³

Scale Height: 8.75 km

Kárman Line: ~108 km

Mean Surface Temperature

10,8°C (modeled from Sci-Fi guide)

        (Hot Desert)

AVG ~ 23.5°C

    (Tropical Forest)

AVG ~ 26.4°C

    (Polar Circle)

AVG ~ -20°C

Earth Similarity Index (does not imply certain habitability)

0,865 from Radius and Stellar Flux*

0,911 from Radius and Surface Flux*

*requires further updates

Suitability for humans?

Pressure and N²/O² ratios are within human-life thresholds.

Ammonia levels are 4x higher than what's considered immediate harm to human life and health.

Carbon Dioxide levels are above 40kppm, and considered an immediate danger to human life.

Breathing Paart's air mixture can lead to fainting or coma in within 10min, and be fatal within 30min of exposure.

The atmospheric pressure at sea-level is comparable to being under 30m of water on Earth, it may cause extreme discomfort and breathing difficulties.

Wearing a pressurized suit is vital for human survivability on Paart's surface.

 

Symptoms of atmospheric sickness manifest in the form of: irritation of the nasal, laryngeal and eye regions, coughing, laryngospasm, edema of the glottic region, strong respiratory stimulation, dizziness or nausea, confusion, headache, and shortness of breath.

What about its suitability for other life forms?*

*requires further updates

MICROORGANISMS

Short answer: the atmosphere of Paart is rather reducing and dense, harmful to Earth-like macro-organisms, but does not present a significant risk to bacterial growth.

On Earth, relatively high ammonia levels in the local atmosphere causes microbes to develop high levels of polyamines (which can include putrescine, a compound that contributes to the smell of rotting flesh), high oxidation stress response, and antibiotic resistance to some extent (particularly, for Tetracycline).

High levels of ammonia also indicate the presence of high-density colonies of bacteria, under mats or embedded in medium / semi-open systems, the exact quantity of ammonia needed to overcome it's 'good' effects and become toxic seems rather unknown due to the small array of bacterial specimens tested, but was demonstrated to be as high as 10~30milimols per liter (or 0,17 to 0,51g/L), which depends on the availability of peptides in the environment for metabolic reactions.

Another study, shows that levels of 2,56g/L (151mM) are enough to impair Earth bacterial growth, however the strain tested naturally lives in environments where the concentrations are in between 3,4 ~ 8,5g/L, in the form of ammonium sulfate, and thus, the figures for ammonium sulfate toxicity may not really reflect the toxicity of ammonia itself. The study concludes that

"Ammonium is in contrast to the situation in animal cells and plants not toxic for the studied model bacteria C. glutamicum, E. coli, and B. subtilis, even in molar concentrations."

It completes, stating that bacteria also tend to choose ammonium over air as a reliable source of Nitrogen - I must also recall that's why we use ammonium compounds as fertilizer for Nitrogen fixation.

This other study points out that bacteria can survive perfectly when exposed to 15,8g/L of ammonium, and some up to 8,5g/L of ammonia.

More specifically, under a pH of 9 (alkaline medium), and above stated concentrations of ammonium and ammonia, only 2 out of 40 strains managed to grow, or 5%.

Ammonia vapor levels in Paart's air are only about ~5,54mg/L (or 2000ppm), which is not even close to what's considered a risk for bacterial growth.

When compared to Earth bacteria (which is exposed to nearly 0% ammonia from the atmosphere), Paartian microbiota may still prove to be slightly more resistant to antibiotics, stinks when isolated, and is highly dense and competitive.

In the atmosphere free ammonia quickly reacts to become ammonium, which falls back to the soil during rain - in theory, this should keep atmospheric ammonia levels close to 0%, however there must be an imbalance in ammonia production vs environment absorption, where in the end, there is a net positive influx of ammonia to the atmosphere via some serious microbial bioturbation from gram-negative bacteria, likely inhabiting beaches and mud further inland.

Aside from the ammonia effects, the Paartene atmosphere is nothing really strange to Earth's microbial collection. However is unlikely other Earth animals could survive its atmosphere.

Water concentrations of ammonia as low as 0,02mg/L are lethal to freshwater fish, and 0,66mg/L for freshwater invertebrates like Daphnias - as we will see later, water contents of ammonia can top at 330mg/L depending on whether or not it's fresh rain or sea-water.

PLANTS

Short answer: the average soil of Paart is rather acidic but fertilized, friendly to Earth-like plant-life growth.

Earth's plants can survive annual concentrations of ammonia around 75 micrograms/m³ of soil (or about 3,75mg/kg), or up to 15 hours with concentrations of 3,4g/L, as free ammonia itself is an inhibitor of photosynthetic phosphorylation, ie, it absorbs the free electron released by photosynthesis.

On Earth, Nitrogen contents in soil can vary between ~2,2 and +200 mg/kg of soil, the latter when fertilized - an arbitrary content of 50mg/Kg corresponds to concentrations of 250kg of Nitrogen per cubic meter, we are assuming a soil density of 5g/cm³.

Using Earth's Nitrogen Cycle (in the Arctic Ice) as a model, we can account at least 27~28% of atmospheric Nitrogen becoming ammonium due to microbial activity.

Given a cubic meter Paartene air has 2,216 kg of N², a 27,5% Nitrogen fixation gives the soil about 609,4g/m³ of ammonium - which corresponds to a concentration of ammonium about 160 micrograms/kg, which may seem particularly poor, but given the ammonia/ammonium ratio at pH 8 (slightly alkaline) an temperature of 20°C, our free ammonia levels are about 6,1 micrograms/L, or ~12 micrograms/L if at 30°C.

It seems that from a purely ground-based perspective, Paart's soil presents no harm to Earth's plant life.

With such high levels of ammonia in the air and higher volcanic activity, one should not be surprised by acid rain falling down to earth.

1L of simulated acid rain may contain up to 2,3 mg of ammonium, 11,1mg of sulfuric acid, 1mg of chlorine, and 7,1mg of nitrate, among other ions.

With 2,59x more atmosphere than Earth, as much more water as that, given both planets present a similar size, an annual precipitation of ~1800mm would not be far-fetched, Paart's atmosphere would rain 41,32mg of ammonium and 200mg of sulfuric acid per square meter of soil, yielding a final concentration of 268 micrograms/kg.

If we consider Paart became particularly rainy over the last 350 million years preceding the Cambrian, we may get an accurate figure of the current soil content of ammonium.

The Amazon rainforest precipitation can range between 2.000mm to 10.920mm, or 2,7 to 14,95x the global average.

Following this line of thought, if the Albanian period bore 8x the typical rainfall "capacity" of its atmosphere, we would get ~14.400mm of rain a year, 19,72x more than the Earth's average - it's not far-fetched that the rainiest period of history would be the one with most ammonia, which is a cloud forming aerosol.

Typical water weathering would erode 112,32 micrograms of material a year (1micromol per 130d from granite).

Assuming a soil moisture of 0,3m³/m³, or 300L of water per 3800kg of soil.

Typical Paartene weathering during this 350My period would erode  +2,215mg of material a year, while the rainfall would deposit +330,5mg of ammonium, the typical ammonium content in the soil would be what it can actually retain, about 8cm deep in the soil, so we are limited to 800ml of water-containing ammonium/ammonia per m³ of soil, or, with a solubility of 31% at 25°C, we get a maximum of 248g, or 65,2mg/m³.

At this rate, 1,3g would be deposited every 1My, and in 246My would be at its maximum.

At the time, the actual landmass area was near to 40~44% of the planet's surface, while 17~20% of the planet's area under a thick sheet of ice - the actual surface area that would be exposed to this kind of treatment would be the remaining +55 million km² of continent, with the polar caps melting and the continent splitting, the water flow would have helped spreading it both inland and wash it away to the ocean, if we assume half of this amount remained inland, we get an average ammonium content of 7,8mg/m³, or 2080x what's considered toxic for Earth plant-life.

With a little more math, we can tell there is about 2,59*10^16 kg of ammonia in the atmosphere at the start, if it's deposited 1,3g of ammonium every million years, with a planet that's 5,68*10^14 m² in area, over the course of 350 million years we would have deposited 0,99~1,02% of atmospheric ammonia, assuming a more smooth weathering process for the past 3.550My, gives us 4,88% deposited in total, once the influx of ammonia production is broken, we will have a drastic decrease of the substance in the atmosphere.

Ammonia normally stays in the air for a week before reacting or self-dissociating (if built up from 10~12 days first), if it built up in the atmosphere for 200My, and we assume a cut-out of bacterial activity, it deposits as nitrite and nitrate over the next 70My, so it's likely to assume these quantities of ammonia won't hold up on the atmosphere for more than 100~150My after peak Albanian period.

Of course, it's also reasonable to assume that the bulk of this material would be embedded in the sediment in the form of ammonium sulfate, given the sheer amount of potential sulfuric acid available for the reaction, the soil would actually have something around 24mg/m³, or 6,3 micrograms of ammonium sulfate per kg of soil, which in by itself wouldn't acidify the soil to much lower than pH 7 (not alone, but the SO4 would do quite some)**, and is inside the 150mg/kg plant toxicity limit.

 

**Corrected calculations for a solution of SO4 and NH3 - point a pH value of 4,58 (rainwater) and 4,79 (wet soil), or similar to that of coffee left over to sit for 24h - however places where the rain is minimum, ie, further inland of Sthalika, the acidity could be as low as pH 6,69 - equivalent to that of milk or Earth normal rainwater.

What if we sell it?

352.620.921,22 (352,62 million) USD from early 2020

45.421.859,93 (45,42 million) USD from 2009