Variations On A Theme Of Earth

[Spacescifi]

Just wondering how far can one take the 'alien earthlike' world concept. From an enviromental POV?

I am not considering lifeforms as I already have that covered.

Some call it Qonos, Romulus, or Minbar, but all of them are mere scifi clones of Earth.

From my own research I have found this:

1. 'Earth' with rings like Saturn? Almost, just think rings of rocky asteroids instead of ice (sun heat this close would melt Saturn's ice rings). Also those asteroid rings will not be in LEO, since they must be in a high enough orbit to be stable and not crash into the atmospheric friction. That said,rogue asteroids would fall probably more here than our Earth.

2. 'Earth' with grass or vegetation with a main color other than green? Possible, although there has to be physically either a chemical or distance to the sun reason,  which has a limit to which it can be adjusted and have an 'Earth' still be livable. Darker colors absorb more sunlight, which is useful for plants that are evergreen...or should I say evercolored...since it can be any color?

Did I miss anything more? How far can we really push the alien Earth concept without breaking it?

[cubinator]

A highly oblate planet? (I highly suggest checking out the theoretically stable toroidal planet as a storytelling setting, but the only plausible way to create it would be artificial)

An Earth with no plate tectonics? (Think Mars if it was a moon of something with a nice big protective magnetosphere)

26 minutes ago, Spacescifi said:

1. 'Earth' with rings like Saturn? Almost, just think rings of rocky asteroids instead of ice (sun heat this close would melt Saturn's ice rings). Also those asteroid rings will not be in LEO, since they must be in a high enough orbit to be stable and not crash into the atmospheric friction. That said,rogue asteroids would fall probably more here than our Earth.

Saturn's rings are thought to be the remnants of a moon which drifted too close over time and was destroyed by tidal force about 100 million years ago. If the same were to happen to Earth, it might be a rather catastrophic event.
Other ideas:

A very cold Earth with ice covering the oceans (This has literally happened to Earth before and the microbial life that was present at the time was fine and dandy)

Binary tidally locked Earths - for extra spice make sure civilization develops on the side not facing the other planet!

[Scotius]

Apparently Earth was purple very, very long time ago:

 

[kerbiloid]

As (afaik) the dollars initially were made green just from pure economy, with the most available color in stock (and it was grass-like), the purple planet would use GBP instead of USD as world currency.

Edited November 8, 2020 by kerbiloid

[Spacescifi]

11 hours ago, cubinator said:

A highly oblate planet? (I highly suggest checking out the theoretically stable toroidal planet as a storytelling setting, but the only plausible way to create it would be artificial)

An Earth with no plate tectonics? (Think Mars if it was a moon of something with a nice big protective magnetosphere)

Saturn's rings are thought to be the remnants of a moon which drifted too close over time and was destroyed by tidal force about 100 million years ago. If the same were to happen to Earth, it might be a rather catastrophic event.
Other ideas:

A very cold Earth with ice covering the oceans (This has literally happened to Earth before and the microbial life that was present at the time was fine and dandy)

Binary tidally locked Earths - for extra spice make sure civilization develops on the side not facing the other planet!

 

Perhaps you broke 'Earth?'

 

Earth's oceans might not exist if water were not periodically subsumed by the planet's mantle and then released. Without plate tectonics driving the creation of coastlines and the motion of the tides, the oceans might be barren, with life-giving nutrients relegated forever to the stygian depths.Jun 7, 2018

Quanta Magazine › plate-tectonics-...

Plate Tectonics May Be Essential for Life | Quanta Magazine

Edited November 8, 2020 by Spacescifi

[cubinator]

31 minutes ago, Spacescifi said:

Perhaps you broke 'Earth?'

Perhaps. Though there are other types of tectonic activity like on Mars or Io which do not involve plates but still recycle material. A moon of a large planet might have a volcanic 'temperate zone' driven by tidal force.

I also heard it suggested in a geology class I took that the inverse of what you quoted is true - water is an important driver of plate tectonics, as it dissolves material in it and lowers the melting temperature of rock, allowing molten patches to form in the mantle and letting Earth gradually leak its internal energy through relatively small eruptions rather than waiting 700 million years to blow up the entire crust like Venus.

Perhaps for a more exotic approach a periodic pass through the debris field of particularly nutritious and gargantuan comets could be the source of new nutrients.

Edited November 8, 2020 by cubinator

[Spacescifi]

11 minutes ago, cubinator said:

Perhaps. Though there are other types of tectonic activity like on Mars or Io which do not involve plates but still recycle material. A moon of a large planet might have a volcanic 'temperate zone' driven by tidal force.

I also heard it suggested in a geology class I took that the inverse of what you quoted is true - water is an important driver of plate tectonics, as it dissolves material in it and lowers the melting temperature of rock, allowing molten patches to form in the mantle and letting Earth gradually leak its internal energy through relatively small eruptions rather than waiting 700 million years to blow up the entire crust like Venus.

Perhaps for a more exotic approach a periodic pass through the debris field of particularly nutritious and gargantuan comets could be the source of new nutrients.

 

Well then the planets life will be short, as comets do not last, unless it is a moon size comet.

Also in such a situation it would rain comet dust and meteors regularly. So hardly safe.

[DunaManiac]

On 11/7/2020 at 11:49 PM, Spacescifi said:

2. 'Earth' with grass or vegetation with a main color other than green? Possible, although there has to be physically either a chemical or distance to the sun reason,  which has a limit to which it can be adjusted and have an 'Earth' still be livable. Darker colors absorb more sunlight, which is useful for plants that are evergreen...or should I say evercolored...since it can be any color?

I could see this happening on planets which orbit around a different type of star like a red dwarf or a more massive star, the vegetation would be a different color to absorb the most amount of light.

On 11/7/2020 at 11:49 PM, Spacescifi said:

1. 'Earth' with rings like Saturn? Almost, just think rings of rocky asteroids instead of ice (sun heat this close would melt Saturn's ice rings). Also those asteroid rings will not be in LEO, since they must be in a high enough orbit to be stable and not crash into the atmospheric friction. That said,rogue asteroids would fall probably more here than our Earth.

Maybe something like this would not be very hospitable to life, as a large asteroid colliding with the planet every several hundred thousand years or so would not be ideal for multicellular life to evolve.

Edited November 9, 2020 by DunaManiac

[kerbiloid]

A radioactive ice moon, glowing blue.

[Terwin]

Green is not the ideal color for photosynthesis on earth, but it was just what was left over as the pink/purple bacteria of the day were sucking up the easier to use wavelengths with competition too fierce for multicellular plants to evolve.

You only see earth-clones on TV/movies because space-suit mock-ups are expensive, heavy, clunky, and uncomfortable, so they are not used unless essential for the plot, and that means earth-like worlds.

Also, if you have the choice between building your base on an earth-like world and an equally strategic barren rock, which would you choose if you care about the morale of your workers/troops?

 

Planetary ring systems are temporary, Saturn's rings are a geologically recent event and will be gone 'soon'(less than 100 million years).  It is entirely possible that Jupiter, and even Earth may have had rings in their (distant)past, they just do not last very long when talking about planetary life-spans(and the in-fall is not great for those living under them).

[magnemoe]

1 hour ago, Terwin said:

Green is not the ideal color for photosynthesis on earth, but it was just what was left over as the pink/purple bacteria of the day were sucking up the easier to use wavelengths with competition too fierce for multicellular plants to evolve.

You only see earth-clones on TV/movies because space-suit mock-ups are expensive, heavy, clunky, and uncomfortable, so they are not used unless essential for the plot, and that means earth-like worlds.

Also, if you have the choice between building your base on an earth-like world and an equally strategic barren rock, which would you choose if you care about the morale of your workers/troops?

 

Planetary ring systems are temporary, Saturn's rings are a geologically recent event and will be gone 'soon'(less than 100 million years).  It is entirely possible that Jupiter, and even Earth may have had rings in their (distant)past, they just do not last very long when talking about planetary life-spans(and the in-fall is not great for those living under them).

The dinosaurs was more geological recent
On the other hand an terrestrial planet with an decent ring might have so much mass deorbiting it would be an major extinction event. 
Joke analyze on destruction of second death star and the fate of the ewoks. 

Now an favorite of mine is an terrestrial moon like Pandora in Avatar. Its obviously tidal locked, your species evolved on the outside. You was their Leif Erikson or part of his crew traveling very far before science and the first who saw that you was orbiting. That would be a bit scary as in underwear get out of fashion  and make some impact as in how many new religions
On the other hand orbital mechanic will come earlier and even space travel is much more practical here. 

[kerbiloid]

As purple algae are the most productive, shouldn't we expect that the Earth of future will look like a mix of green (wildland) and purple (algae farms) spots?

[Spica]

Purple algae as they may have evolved on Earth would face many obstacles today and in the future.

First being that green plants reflect away the green light that purple plants need. Green plants dominate the productive regions of the Earth, leaving little room for purple plants to take hold.

Additionally green plants produce oxygen which would have been highly toxic to any purple plants that came before, just as elemental chlorine is toxic to green plants and other aerobic organisms around today.

And anyway, green-plant photosynthesis as it stands is such a "hard" process to evolve that it seems very unlikely that a new, dramatically more efficient process would arise in the future without drastic changes to Earth's chemical environment.

[kerbiloid]

That's if mix the green and purple plants in the same biosystem.

But I mean: green plants in wild nature and gardens, and purple algae in hydroponic vats with no contact with the external medium. An agricultural industry.
All we need from the algae is cellulose and basic proteins, and they can be probably fed with methanol and ammonia, or so. This presumes that they are fully isolated  in any case.
So, the greens and purples wouldn't affect each other in any sense.

Edited November 10, 2020 by kerbiloid

[sir rocket]

On 11/7/2020 at 8:49 PM, Spacescifi said:

1. 'Earth' with rings like Saturn? Almost, just think rings of rocky asteroids instead of ice (sun heat this close would melt Saturn's ice rings). Also those asteroid rings will not be in LEO, since they must be in a high enough orbit to be stable and not crash into the atmospheric friction. That said, rogue asteroids would fall probably more here than our Earth.

How much damage would this deal to the poles, because maybe life could evolve there? When I can I'll simulate it

[Spacescifi]

21 minutes ago, sir rocket said:

How much damage would this deal to the poles, because maybe life could evolve there? When I can I'll simulate it

 

How will you simulate it?

Also...as for origins, I am not worried, since in my scifi life origins are actually KNOWN. For at least SOME races

Because:

1. Some scifi races are born biologically immortal. The first ones (their dad and mom) are the stuff of legend and are rumored to be in hiding ever since they had a falling out with their children. These immortal races have a nigh impossible time not being mindful of their origins when their culture is impacted heavily by rivalries lasting for millenia. To cut the story short...some support the idea of Dad and Mom ruling, yet by far and large most do not, and tend to attempt to sway those who do from doing so.

2. Mortal races also exist. Some still debate their origins (like IRL Earth). Yet some other races do not concern themselves with such topics at all, as they rather spend time working out their aims on a grand scale.

 

[sir rocket]

14 minutes ago, Spacescifi said:

How will you simulate it?

universe sandbox

[Spacescifi]

1 hour ago, sir rocket said:

universe sandbox

 

What program? KSP?

[sir rocket]

It's a game. search it up on steam.

[Spacescifi]

2 minutes ago, sir rocket said:

It's a game. search it up on steam.

Name?

Universe sandbox?

Either way...I look forward to seeing your results.

[sir rocket]

Just now, Spacescifi said:

Name?

Universe sandbox?

exactly

1 minute ago, Spacescifi said:

Either way...I look forward to seeing your results.

probably tomorrow