Super-Earths and optimum habitability

[Coinneach]

It says here: https://www.space.com/super-earths-more-habitable-finding-more that "the most habitable planet would have roughly twice the mass of the Earth and be between 20% and 30% larger by volume".

Why?

Does optimum habitability depend on optimum gravity?

 

[rod]

IMO, no exoplanet confirmed to date, is shown to be better than Earth for life or that life lives on an exoplanet today. We have more than 5500 confirmed now and so far, no confirmation of a real, earthlike exoplanet like we live on here.

NASA Exoplanet Archive

exoplanetarchive.ipac.caltech.edu

Encyclopaedia of exoplanetary systems

This encyclopaedia provides the latest detections and data announced by professional astronomers on exoplanetary systems. It contains objects lighter than 60 masses of Jupiter, which orbit stars or are free-floating. It also provides a database on exoplanets in binary systems, a database on...

exoplanet.eu

 

[Helio]

The article could use some updating from its publication a little over a year ago....

1) Although Super Earths are more common than Earth-sized planets (a little more than 2x more common), it is Mini-Neptunes that are the most common, 3x more so than Earths. About 1/3 of all exoplanets of know radii (3969 of 5535) are these Mini-Neptunes; (625 of 5535 are Super Earths). [Uses 1.9x Earth rad. to 3.1x as Mini-Nep.]

2) Also, there are more known Mini-Neptunes orbiting M-type stars (mostly red dwarfs), not Super Earths.

3) We don't have a lot of data that includes both the star type and radii to get a clear picture yet. Only about 1000 exoplanets include both.

But the arguments the article makes favoring larger planets are worth noting:

1) Larger planets found in the HZ are very likely more massive, thus more likely than not to have a large iron core producing a protective mag. field. [Earth got lucky when Theia donated its iron core when impacting Earth and bumping our rpm.]

2) The idea that they would have shallow oceans is interesting, but if correct, could be important to life because lots of shorelines may be important, and having light reach the bottom may be important, as noted, as well.

3) Larger atmospheres are likely that help keep the planet warm enough for liquid water should be helpful, but not always.

4) Tectonic plate activity would be more likely on more massive planets, but radioactivity is also important to generate necessary heat. The older red dwarfs, I think, might be Pop II stars that might have less concentration of radioactive elements.

The long-life of the red dwarfs seems important to give life more time to develop, but more and more, red dwarfs are found to be constantly throwing tantrums -- large flares and storms that would likely be detrimental to evolutionary life forms.

Of all exoplanets, there are only 153 known that are in HZs (+ or - 10% beyond the calc. zone). Only 10 of these are Super Earths. There are 14 of these that are Earth-sized, so I'm unclear where their data is coming from.

 

[Phillip Huggan]

My avatar is an illustration of Fathom, a water world 130 LYs similiar sea and air composition. Earth often has nitrous oxide and ammonia for water but nitrogen atmospheres should be there, Another class every 200 LYs is gas giants that shrink by exploding core radiation. Here you take away some or all of the sulfur that has kept ammonia away (0.2% mostly 0.5% with hidden). Ozone is in the air and 1/4 magnetic field. You'll get sulfur species up to wombat sized. I'm there for a millenia of biology and 500 yrs after we will have water on the road getting 2x usual ship compliment. Those objects would be there for the taking still. You'll new food and restart species lists. There is a field from the salt no amphibians. We need to get the nutrient rich water that makes the other 1/2 way up like Tom Hanks described, and bring to poles. We'll desalinate lots of replenishing minerals. There are 600mph storms at least every location each 6 yrs. It has three ocean layers, bottom deep rust blue (200km Fe), middle translucent (500km Sulfur) top is bright orange or blue (130km mixed). Any ice often encases a world.

 

[Phillip Huggan]

It is habitable for micro-organisms not person habitability. There were 18 people on the inner circle for the 8 hr painting. I went hiking while 16 people intercepted 6 hrs of data.
Clades I learned in 2020 w/ help. The nature is mostly new including 100x the ocean species to date where disease isn't an issue. Every type of fish will be obsolete when the new ones are able to be customized to an ecosystem free-ranging. All the rodents will be upgraded to surviving disasters. All the plants will be better as they will be optimized for their light and heat. Obviously not for Earth itself. Desalination and water management will be better. There will never be survival here more than a 200 person Navy. We need to submerge when storms hit or evacuate on a moment's notice. The membrane filters draped around the pods should be partially submerged. Genetics here will tell us how much exercise we need. The air will take 200 yrs to filter. The water has many hazards but most of it can be cleared of hazards. It is hard enough to motivate me and we'll know if nature without land is good. Aerogels and hydrogen are the key to floating and rising above the atmosphere.

 

[billslugg]

1) Larger planets found in the HZ are very likely more massive, thus more likely than not to have a large iron core producing a protective mag. field. [Earth got lucky when Theia donated its iron core when impacting Earth and bumping our rpm.]

Iron is 0.109% of the Milky Way galaxy.
Iron is 0.117% of the Solar System
Iron is 0.014% of the mass of the Sun.
Iron is 31% of the Earth's mass

Iron is needed for generating a magnetic field to deflect cosmic rays.
Iron is needed to give higher gravity for higher atmospheric pressure.
Iron is needed for radioactive decay of the associated heavier elements in order to drive tectonic activity which is needed to sequester CO2.

Earth sure did get lucky. Even without Theia, we had an awful lot of iron.

 

[Helio]

Earth sure did get lucky. Even without Theia, we had an awful lot of iron.

It’s a safe bet that all inner planets have lots of all the metals for their size. I think Mercury is close to 3x that of Earth.

But it’s likely Theia‘s heated embrace was fortuitous, giving us a large, stabilizing moon, and perhaps some nice spin for the mag. dynamo.

 

[billslugg]

Moon is essential for tilt stabilization, also gives us the tides without which estuaries would not flourish.

 

[Classical Motion]

For some reason, educated men deny obvious design and perfection. They proclaim the design is only apparent and the result of randomness, probability and time.

Where do we find such men?

Perfection from chaos.

 

[billslugg]

Yes, perfection from chaos. It's hard to believe until you consider just how much chaos there was. As for any kind of intelligence designing things, who designed the designer?

 

[Classical Motion]

I do not know. I have yet to meet them. The designers might not be generational.

But chaos, randomness and probability are forbidden within this design we live in.

Chaos, randomness and probability are only terms for ponderment, a rational for the unknown, not reality.

Understanding always dissolves these concepts. Or I should say it use to.

Today they are welcome and needed fundamental concepts. And a balanced math equation with them is the goal. Considered success. The solution. A successful non-answer.

Could chaos, randomness and probability result in a singularity? How many singularities do we observe?

One and only one. Earth. And it's alive. And all alone.

But an explanation of coincidence is acceptable for most.

I like a little more meat.

 

[Phillip Huggan]

Orb classes: Earth's w/ nitrous oxide not forming is < 12/galaxy. Desulphuring 1000 a galaxy is there. Brown Dwarfs all have different color, are a safe bet as you can image them and have some simple predictibility, down to 60 good ones in the donut middle. Just nitrogen air is 50 in milky way, inert enough to terraform if good soil. Ammonia is permanent bad reactions and cyanide is tough to keep VIPs safe but oceanic life might survive light worlds (probes to far visible objects easier). Comet aggregate hopefully a copper asteroid coating are a grab bag of good and bad stuff but dynamic water is here outgassing faster than Mach 1....ozone layer science best.
Coal slate and stellar cores are inert. Worlds get made w/ inert gases in the soil so terraforming land may be easy and medical air is there but fluorine too. Bedrock granite can be dug into, usually is too chemically reactive. The odd big star might see VIPs at Oort and many new classes riskily visited. Colder is safer chemically and hot is few H2O reactions.
Former gas giant will not need to decontaminate land if all ocean. Magnetic reversal makes 20C-24C poles different circulation each 8 yrs. No soil, carbon makes toxins. 100km/h floating surface speed needs OK computer storm tracking. Fluorine in the jetstreams need more than drones skimming the gas off (gets 1.1g down and water out past GEO). 200% humidity 1/2 the surface will need drier pole cities. Only global gliders keep the air pure. Aerogel turbines above the too high vapour pressure. Smoother waves briny salts keep clumps from holding toxins.
Ravens maybe a king predator. Sea life (for Earth too) turns brown to avoid sunburn. 1000 yrs to mutate to pole only magnetic fields. Any swimming mammal can be exported to Earth. 20 animal ecosystems is the goal. Hoping the heat keeps the poleward, but filtration enough should enable 100 km whale ranges, they can ping the bottom. The centre ocean layer smoker risen nutrients after a storm are collected to feed everyone. We'll have 100k new species of shrimp and crab. Any ship habitat will be optimized for great ecosystems. There are no doubt other gas giants resembling classes other than Earth without land. The 200 aquamen will have ships city sized. The rest of us will be in asteroids 1 LYs away, climbing 3.5 hrs/day. There are likely 3 here and 12 in Andromeda better than Earth assuming terraforming in an ice age time. Andromeda has ice rocks surrounded by 3d waterways in one colder object. Maybe in a trillion yrs it can be made...

 

[Phillip Huggan]

Skimming the air off between LEO and GEO taken to between the brown dwarfs or to Oort bases. You "land" and takeoff using H2 or O2 in the air.
Turning O3 to O2 is needed. Then the jetstream velocity must be matched and dipping into it to filter some F out with a plane hopefully mass produced with desalinated materials. Fadeout is a communications blackout globally but not orbit when the winds anywhere reach 1000mph. Comms can't be used because the core has become charged with electricity (sea bottom) surface mostly. It will no longer be safe to go to orbit once the ions curve the motion of the air downdrafts happen 1000mph randomly as the ocean is now pulling the air to the surface via electrostatic newtons in the sky altering vapour direction. Orbital rescue w/ optical computer will reveal 1/2 the surface as safer to attempt retrieval.
The animals will be with lots of new islands dropped from He balloons sailing away from the storm. There will be green seas of fresh water drinkable for them for a day or two. They might evolve to drink this water only here. 8^0 from the poles it turns saline but is 1/2 and 1/2 before then w/ pockets of fresher water. They will cry and if die the admirals have to see how close they are to making it. If riding it out human pre-storm prep involves forming an escape-ship chain and jetting underwater faster if pooling fuel.

 

[Phillip Huggan]

Km of freshwater lens lasts 1 yr, 100m lasts 45 days. Surface floating pipes can distribute ponds to a lake. Thermoelectric is from the 2 dwarfs and 100km/h wind power is everywhere (30 poles and 130 equator avg day) but wave infrastructure is mucked. Diamond a shelled probe hits the surface floating and admits the 10% O3 turning it to O2. Buffering is the norm for super Earths, the ozone protected from radiation or 1/2 the time the world historically crusted rad rxions. Sulfur in the air is replaced with N or oxidation. The sulfur in the air need to get <2% and <5% in the water (1/3 of changes revert after a millenia and 2/3s 10k yrs). The seas salts can only be dropped 10% or precipitates happen. Bromine sunk but K salt is bad for life. Within a century we should be able to do top sulfur bio and better than smog in 200 yrs. Storms bring up sulfur 200 km from surface. The air breathers go 500km and the other 500km way w/ O2 on the way to eliminating fluorine but inert gases should be brought not harvested. 1km^2 can be dried out as pneumonia happens...not supposed to cut the water vapour in 1/2 but 1.4 bars avg is a lot. 100k Earthlings can come after for terraforming the salt ocean 0.65g Neptune world at 220 LYs there is a mineral spa planned 20 LYs from Fathom I'll wait there. 0.5 LYs away the Oort is good but the system is deadly, 0.5g asteroid cobble at best the spas are safer for water. The frozen tidal wave world between the 220LY destinations got frozen because of a moon but it can be walked on at least now...

 

[Phillip Huggan]

An equator photo of TOI 1452 instead, also maybe the last yr the Angevin Empire was expanded...

 

[Phillip Huggan]

10k-100k biosensors are good enough we could've gone. Another super Earth I'm interested in is around Sirius the 1.2g granite earthquake world apart from two Cali areas. Hitting winter CO turning into to late Spring CO a lithium patched sea good for coral reefs not fish. Then I get a 1.2g glaciered world w/ H2O2 from core to lift it and reveal granite. Hourly Mini flares night only for me and 10x worse than sunburns for animals. Sirius needs a rocket fuel substrate not enough oil. I can work on Procyon and Sirius from Neptune.
I think the idea is to get it <1.05g b4 the nova. Mine is 5C but 10% O2 surface water isn't allowed animals need caves to drink. Then an Earth two for 100k yrs 20% water 10C. I'll try to pry an Ag asteroid from Procyon and get one nanorod Jetsons building on Sirius and get to 1.14g mice dead in a week and more power than Earth for the system.