Teegarden's Star and its two planet candidates

[AstroChara]

Got the news from OA's Facebook page. Apparently, there might be two Earth-massed worlds orbiting around the star. The first one orbits in 4.91 days, and the second one 11.4 days. Both planets' minimum masses are 1.1 Earths.

https://www.centauri-dreams.org/2019/06/...red-dwarf/

https://www.nationalgeographic.com/scien...dens-star/

Considering the star, it probably didn't have enough material in the disk at where both planets orbit, so they (or their material) would have to migrate from the outer system, like TRAPPIST-1's seven known planets. It is probably equally likely that Teegarden b is a rocky planet or an ocean planet, but Teegarden c is most likely an ocean planet, AKA a planet covered by tens, or even hundreds of kilometers of water.

For Orion's Arm, I can already hear Rynn saying 'no' to terraformation, so we should go for something else. Creative ideas welcomed

[sandcastles]

Maybe on the ocean planet, there are a few whale-like creatures, call them Hwaets.  The creatures are so huge, they are like islands, many kilometers across.

They are peaceful herbivores.

Another group, similar to sharks, call them Hsaiks, are the constant enemies of the Hwaets.

Most other life is somehow connected to one of those creatures.  What they do is either parasitism, symbiosis, mutualism or commensalism.  

Other species, even the plantlike life, tend to gravitate toward either a Hwaet or a Hsaik for protection.  (That doesn't really work very well, since the predators are going there, too.)

A few other species have no interest in either, and they are the main food of the Hwaets and the Hsaiks.  Examples are seaweed kilometers long, life similar to plankton, flying electric eels, aggressive sea anemones and swimming coral.

Occasionally one might catch a glimpse of chemosynthetic tube worms a kilometer long/tall, some of which have detached from the ocean floor and began to float.  Some are using compressed air or methane for propulsion and/or defense.  

Another flying creature reproduces with eggs.  But there's no land, and the eggs might get eaten by the creatures living in/on the ocean.  So the eggs have glider wings, and float in the air for days.  They aren't released from the bird's body until they're almost ready to hatch.  So the eggs float in the air until some ppredator tries to eat it.  The egg hatches and the baby eats the predator from the inside.  I guess that would work just as well if the eggs were laid in a nest, but I was trying to excuse the floating/flying eggs.

Most of the planet is ocean, and the gravity is higher--two factors which inhibit spaceflight.  But the sentients' astronomy is very good, they know about Sol's planets and hope somebody will come help them leave their planet.  

Maybe the reason they can't leave is the Hwaets and the  Hsaiks are the sentients.  It would be an interesting and enormous task to get them into orbit.  
Their relationship could be a Cold War, very civil to each other, but using spies and proxy wars.

I've read that a denser atmosphere is more significant than a lower gravity, regarding whether creatures evolve flight.  But this ocean world has several moons which drew away some atmosphere, so the atmospheric pressure is the same as Earth's.  So they don't have balloons or large flyers.  The tides will be complex, so swimmers will have to develop the intelligence to adapt to the tides.

In Orionsarm, is there a description of launch platforms on water instead of on land?

I have another crazy idea.  Planets can have continental plates which move around.  Maybe gigantic scaled creatures can have scales which for some reason move around like continental plates, I don't know why.  And instead of pimples, they have something like volcanoes which spew forth stuff...I hope you didn't mind reading that
 suggestion!

[Drashner1]

I like the basic idea of the xenosophonts, but placing such so close to Sol would require major restructuring of the OA timeline and many (possibly many many) articles throughout the EG. As such, I would suggest shifting sandcastle's suggestions for this world to someplace in the Hinterregions or Outer Volumes (red dwarf stars are common, after all).

Re what might be done with the planets around Teegarden's star:

Perhaps the water world could be home to a mix of aquatic tweaks, provolves, and neogens adapted to different depths. Perhaps the second planet could be a dry world and home to one or more clades of vecs adapted to the high temperatures.

Just some thoughts,

Todd

[stevebowers]

Even if these planets are tainted by carbon monoxide, they could still probably be made perfectly habitable. In the worst case they could be inhabited by tweaks or neogens. Note, however, that this star is only 12 light years from Earth, so it would probably be an early target for colonisation. Tweaks and neogens that could withstand an poisonous atmosphere would probably not be available in the early days of colonisation, so the colonists would presumably live in sealed habitats or in space for at least a thousand years.

[AstroChara]

As for my own idea,
The star system was colonized by a group of ahumans early on. These ahumans apparently sculpted the inner planet (I want to name it Pravdo/Pravdo’s world, after one of the co-discoverers of the star)’s crust into some weird block-shaped (computronium?) mass. The majority of the AIs lived in the ocean world (Hicks/Hicks’ world, another co-discoverer), however.
The ahuman system later opened up to the Sephirotics, and various biont clades settle both worlds. Pravdo was partially/completely terraformed, but the weird terrains were preserved. The original AIs have mostly moved into the ocean world, databanks elsewhere in the system, or left the system entirely.

[sandcastles]

I'd like to look for another star for the planet I posited.
Whats the closest the two planets come to each other? I was thinking of a long cylindrical habitat which orbits between the two planets, transporting visitors and cargo from one planet to the other.
And maybe the microorganisms in the water world oceans have some strange, unexpected effect on one or more of the AIs living there--it might be something the AIs allow/tolerate. Maybe an AI absorbs some and is altered somehow.

[Drashner1]

I'd like to look for another star for the planet I posited.
Whats the closest the two planets come to each other?   I was thinking of a long cylindrical habitat which orbits between the two planets, transporting visitors and cargo from one planet to the other.

I don't think orbital mechanics would allow such a structure to work. Everything is moving in a different orbit and orbital velocity - so planets or habs could be relatively close to each other for part of each year - but they couldn't hold position relative to each other. And interplanetary distances are too great for anything made of conventional matter to bridge them.

And maybe the microorganisms in the water world oceans have some strange, unexpected effect on one or more of the AIs living there--it might be something the AIs allow/tolerate.  Maybe an AI absorbs some and is altered somehow.

A cybernetic AI wouldn't be effected by micro-organisms. Or would have systems to remove/kill any such that could effect it. Maybe the AI could be biological. However, what 'alteration' are you proposing that would fall within OA Canon? And what could any living organism do to or for a Terragen AI that it couldn't just do some other way?

Todd

[stevebowers]

Long cylindrical habitats that travel between two nearby planets are called Aldrin Cyclers, since the idea was discovered by Buzz Aldrin. Is that what you mean? We've got one that travels between Earth and Mars in the scenario, known as the Valparaiso:
https://www.orionsarm.com/eg-article/51802602b7abd

More about the Aldrin Cycler here
https://en.wikipedia.org/wiki/Mars_cycler
Note that for a cycler to work, the planets don't need to be particularly close together.

[sandcastles]

I was thinking of Aldrin Cyclers, thanks.

I don't know if my idea about the biologicals made sense, but I think maybe a sufficiently advanced AI with free will might decide to do things its creators hadn't intended, like ignoring its purpose, ignoring its creators, turning itself into a Space Whale and absorbing the Aldrin Cyclers into itself, etc.

[Drashner1]

I was thinking of Aldrin Cyclers, thanks.

I don't know if my idea about the biologicals made sense, but I think maybe a sufficiently advanced AI with free will might decide to do things its creators hadn't intended, like ignoring its purpose, ignoring its creators, turning itself into a Space Whale and absorbing the  Aldrin Cyclers into itself, etc.

AIs operating as independent entities with free will are an everyday occurrence in Terragen civilization. So what you describe is certainly possible.

Todd