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An extrasolar world covered in water? (umontreal.ca)
157 points by Brajeshwar on Sept 1, 2022 | hide | past | favorite | 142 comments



Is there a better source? “Freethink” seems to be confusingly mixing terms.

FWIW, we don’t have telescopes to resolve the surface of planets like this so they’re using inferences to approximate composition and extrapolating surface characteristics. Ie by these methods at a similar distance the statements are roughly equivalent to what we’d say of earth if we were seeing it at this distance. The crucial takeaway seems to be it might have a proper water cycle with or without surface rock.

Edit-another comment or pointed to https://arxiv.org/abs/2208.06333



It's around 100 light years away from Earth for anyone interested.


Programming machines to make the trip and then seeding with human life seems to be the best answer to distance.


I have enjoyed reading "The Songs of Distant Earth" by Arthur C. Clarke which talks about seed ships and the culture rise from that. It's an interesting read.


Another book along those lines I enjoyed reading was "Children of Time" by Adrian Tchaikovsky.


Wonderfully written, but for my shame I expected a different storyline and put it down a year or so ago after only reading 60 pages or so and haven't gone back to it. I keep packing it one times away, but... .

One day I might learn how to have a kid AND read books :/


I started reading the Foundation trilogy out loud to my infant. One gets through the books a lot more slowly but it works! I must admit that even if he falls asleep I'll cheat and finish the chapter (still reading vocally).

Bonus: it lets me practice voices for DM'ing DnD games


haha, I should try that perhaps - particularly as I happen to have been carrying Foundation around in my bag and barely managing to read about two pages on my commute :) I never was good at reading when there's interesting Life to gawp at out the window.


The seeds of humanity won't be humanity at all, but the AI.


I’m imagining a spaceship landing at a deserted planet millions of years in the future and then just sitting there, generating pictures of cities in the sky and Mona Lisa on a surfboard.


Kind of a fun hybrid where AI is clearly dominant in an established solar system, but it ends up being impossible to miniaturize the enormous supply chain necessary to fabricate microprocessors, so to colonize a new solar system it actually ends up being necessary to send self-replicating carbon-based humans who will then bootstrap the industrial supply chain necessary for AGI.

(repeat ad infinitum for the rest of the galaxy, humans live only on the frontier)


Who came first? The AGI or the human?


I think we'll figure out how to give your brain access to something like an AMD Ryzen long before we figure how to make a processor into an AI or make one that's concious.


I'd buy that book!


It's all fun and games until you think about the practicalities of building a self-repairing machine that can keep running for hundreds/thousands/millions of years with no significant software or hardware errors.


I’m reminded of the starship Destiny in Stargate Universe.

The Destiny spaceship travels from one Solar system to the other, and occasionally dives into stars to refuel itself.

https://youtu.be/8iXoK39yLQM


A thinking machine would handle errors. That seems simple. Are you imagining that "AI" would be a static piece of code?


Specifically without becoming a paperclip optimizer.


It seems that there's a very pessimistic trend with regards to estimating the feasibility of engineering human biology for inhabiting outer space. Everyone just wants to let AI do it. I think this is because the progress of biotech has been so glacial. This is largely due to regulation. China will probably change the rules around at some point to allow for more flexibility here, with lots of moral outrage and handwringing in the west, and speed off into the future.


Well, I think that's really just an implementation detail. The point is that we will engineer our successor beings, whether than engineering is computery or mad sciencey or both.


Another book Bobiverse series


That would be so interesting - could be many a sci-fi stories created on that premise.

Some mechanical robot/starship storing frozen embryos for 100 years to be released on a far-away exoplanet, the starship taking care of them while they grow up and learn how to live on this new world - the beginnings of a new civilization - a technological adam and eve of sorts.


http://localroger.com/k5host/pitv.html is my favorite take on this


I feel like the reverse situation kinda writes itself as a sci-fi horror short story:

You've got people living their every day lives, when a probe from space lands and starts producing aliens. At first it's treated as a strange curiosity, but with time the aliens begin to make inroads conquering the planet. Ending twist: the aliens are humans, and the "people" were aliens!


"And All The Stars, A Stage", by James Blish.



You might enjoy the short story collection Children of the New World[1] by Alexander Weinstein. One of the stories, Saying Goodbye to Yang, was recently made into a movie called After Yang[2] staring Colin Farrell. The movie has a super-catchy opening credit sequence.[3]

[1]https://app.thestorygraph.com/books/31cd88d8-d8d3-4414-b38c-...

[2]https://boxd.it/lx5a

[3]https://twitter.com/A24/status/1499114323314151425?ref_src=t...


The best exploration of this theme that I have read, was an East German SF novel from the former GDR. Unfortunately, as far as I know, it has never been translated into English.

Here is a very short synopsis on the authors website in English: https://steinmuller.de/en/sf-literatur/science-fiction-buech...


Raised by wolves


And Interstellar



And 2001 Nights.


But hopefully the story would actually be interesting


We can’t do lightspeed with the best tech available, so it’s more like 300-400 years probably.


Don't have to go light speed, thanks to relativity. If we could achieve and sustain even 1G acceleration, live humans could make the 100LY trip in approx. 9 years (spaceship time). You could leave, visit the planet, and come back only 18 years older and tell the next-next-next-next-next generation all about it.

EDIT: To be fair, 1G over 100LY will result in a maximum speed around 0.9998c so I guess you would have to approximately approach light speed for this trip.


True, but we can only manage 1G for minutes, and even hours is a pretty far off.

Without exotic tech like anti-matter or bending space time nothing is particularly close to light speed. Even city size laser arrays are targeting 1-3% of light speed .... for a few grams!

It's a mind boggling amount of energy to get any decent fraction of the speed of light, even without the relativistic increases in mass.


cut that is half. You have got to decelerate to a near stop, much less zip past by your target.


Mo' acceleration, mo' trolley problems.

Go on vacation; come back; everyone's dead.


Alright, alright, alright.


At those speeds you will have problems with the rocket equation even if you have an mass-to-energy drive.


Is this really how time dilation works?


Speed through space + Time adds up to the speed of light or something like that (not a physicist). So as you get closer and closer to the speed of light, your motion through time (from your point of view) slows tremendously. So a few years to you, could be centuries to outside observers. Source: some Kip Thorne lectures I saw like 15 years ago.


It’s interesting that space and time are so intrinsically linked. So space “needs” time and vice-versa. I would love to be able to take an peak behind the curtain how it all works (as I think the relativity theory is rather descriptive, not the true mechanism)

I mean (so Energy is massaccel^2) so does that make space and time equal to energy.

i need a coffee for this one*


Yeah, I just try to learn a bit of the high level "understanding" of how the experts say things like time dilation work, but that's about it. I don't try to extrapolate what little I know as it would likely all be nonsense without a full understanding of the math of all of this stuff: relativity, quantum mechanics, cosmology...etc. Not that it isn't good to think about this stuff.


Yip, although there's also length contraction in play. The universe just starts contorting itself to ensure nothing ever exceeds the speed of light.

What the GP post is referring to is called a 'relativistic rocket'. You can find plenty of calculators for them, like here [1]. It leads to really mind-bending scenarios. For instance a single human could easily travel a billion light years within their lifetime, requiring "only" to travel at 1G acceleration for 40 years. Of course in that time a billion years would have really passed outside of our relativistic rocket.

If it ultimately turns out that there is no fundamental law of the universe that makes long-term rates of relatively low acceleration impossible, then the future will be a simply unimaginable place. Time itself will start to lose meaning as it becomes as variable as distance is today, at least for those able to travel.

[1] - https://www.anycalculator.com/starshipcalculator.html


Yea, the calculators really help show how wild it is. I could outlive Earth's sun by simply accelerating away at 1.25G for ~35 years (ship time), not to mention how stacked I'd be from the workout of merely existing at 1.25G for half my life. The very concept of simultaneity is completely whack at such distances, times, and speeds.


But more importantly - will we be able to do that Superman movie trick where we just fly around the sun EXCEEDING the speed of light so we can go back in time?

Joking mainly. With this much time dilation it would be fascinating to just send out tons of probes in different directions at high speed and constant acceleration - this would massively extend their service life - and potentially also massively extend our knowledge of the universe as well. Of course relatively to the people on Earth it would take a long ass time.


"The universe just starts contorting itself to ensure nothing ever exceeds the speed of light."

This pretty well describes what it's like walking around in a game. Everything looks and acts pretty normal and rational up close, yet I can walk across a continent in a few minutes, yet each individual step along the way looked normal.


Better stock up on antimatter.


We’ll never get governments to approve and fund this. Elon/Bill if you’re reading this you have to do this going rogue. Make it happen. Send human life out to a hundred different planets!


Or possibly long hibernation could allow adults to travel too.


I doubt this. We seem very hesitant to seed any world with any kind of life, even going through great lengths to ensure no errant bacteria get carried on a rover or something.

If we were serious about spreading life, we could loaded up some rockets with basic organisms and throw them onto whatever worlds we want to seed, and then a few million years of evolution should take care of the rest.


I have thought about this a lot. I have said for a long time that human space exploration doesn't make any sense to me. Space is so hostile to our life in general it seems that only purpose-built machines make any sense for the job. But of course for the preservation of our species, we would want to be able to send the "seeds" of our ecosystem to other places.

But then, if we have progressed to that level of technology, where we can send cells or even just DNA with the machines to be cultivated far away in the distant future... would we even bother? Would we even consider ourselves distinct from the machines by then? Honestly I'm not sure. It could very well be that we consider our creations to be our "children", so to speak. Destined to inherit the universe as we pass gradually into the dust from from which we came. It seems inevitable if we eventually crack AGI or artificial consciousness.


We would probably be better off seeding just some basic life first well before humans - give it time to adapt to the local environment and setup shop. Of course this could also backfire (in that it might evolve to be very hostile to human life) but if there is one thing humans are amazing at it is outcompeting other potentially hostile forms of life.


> But of course for the preservation of our species, we would want to be able to send the "seeds" of our ecosystem to other places.

Or we could, you know, take better care of the planet we’re already on.


Tell that to the solar flare that randomly burns everything on it... Or the asteroid that crashes into it... Or the black hole that eats it... Or the aliens that invade it... Or the plague that kills everyone on it... Or the supervolcano that causes "nuclear" winter...

We could be doing our absolute best and still be surprised pikachus anyways. And there's no scifi remedy that will help us resolve these problems, we're not even K1, much less K2 - who's on Earth when it comes dies.

As the only known example of intelligent life in the observable universe, we should be doing everything we can to preserve ourselves. Having everyone on one planet is not a good idea if you're looking for survival on geological timescales (and/or have bad luck).


I think the AI will find little reason to take us with them to the stars.


I don't understand people who say things like this. If we invented AGI tomorrow, how would it achieve domination over us humans?

It is like Voltaire, Rousseau, Locke, Milton, Hobbes, Rawls never even existed and we don't have any sort of coherent understanding of political philosophy and how power is gained and enacted at the consent of the governed.

I also find that discussions of interstellar travel tend to conveniently ignore the fact that a society that develops to the point where this is feasible, must necessarily also have developed to the point of a fully post-growth economy, which leads to fundamental questions of why that society (or parts of it) would seek to undertake interstellar travel at all. It's a boring answer, sure, but many facts of life are quite boring.


> If we invented AGI tomorrow, how would it achieve domination over us humans?

Completely depends on if super-intelligence is possible from that AGI model, and if so, how fast the ramp up will be to super-intelligence.

The problem for insects is not that humans "dominate" them (in fact most insects have total "freedom"); the problem is that humans do not take the concerns of insects into account for any of their decision making.


> If we invented AGI tomorrow, how would it achieve domination over us humans?

Biological evolution takes millions of years to improve human intelligence. Artificial intelligence will be able to develop and deploy self-improvements within years, compounding its abilities.


I get that hypothetically these AGIs would become very smart. But it's not like being very smart is the main criterium for gaining power and becoming a world leader?

All real power stems from old men talking in country clubs and golf courses. The super-smart people work in labs and universities and earn decent salaries while worrying about publication and citationd statistics and journal impact factors.

How does the AGI go golfing?


For what reason would we want people physically close to this thing?


Who would raise them?


The robot from I Am Mother


TIL we can use seeds to create hu-mans. So cool!


It is a bit of hubris for us to think that we are the ones to travel the stars and not the AI we create.

The "robots" will have little incentive to seed humans when they get there.


Fortunately my blender doesn't need an incentive to grind fruit, only a hundred and twenty volts.


Ah, but what makes you confident humans (or any other animal) isn't likewise acting deterministically with just a veiled illusion of free-will and incentive?


From physics point of view, I guess everything is deterministic. But from a human point of view, the question is irrelevant, because we can only experience reality as humans.


Your question sounds like a troll, but it's actually a fascinating one. Reminds me so much of reading Descartes and essentially asking, "How do I know I'm not asleep and dreaming?"


You know you're awake because reality has continuity and makes sense.

Conversely, dreams are fragmented and implausible. You can train yourself to check this to lucid dream (become aware that you are dreaming).


I've had vivid dreams where I was completely convinced I was in reality. Continuity was maintained well enough to fool me. How could I know I wasn't in a dream? How can I truly know beyond doubt that I am not in a dream?


Yes you can sometimes do that (I've lucid dreamed quite a few times before and it's pretty wild), but it's nowhere near 100% reliable. you can get pretty good with practice, but even then it's not a scientific test. It's more of a process of reasoning and gut checking. The human mind can fill in an incredible amount of detail when needed. In one lucid dream I was playing a song on the guitar that I had (as far as I know) never heard before (myself in the dream was inventing the song). I realized I was dreaming before waking up and practiced the song over and over so it was stuck in my head, and then immediately after waking I wrote down the tablature. It ended up being a pretty good song, and (at least so far) I haven't heard anything else like it.

Obviously this is heavy anecdata, but I've never heard a scientific explanation of how to be certain whether or not you're dreaming (or as Descartes describes, being deceived by a demon).


>it's not a scientific test.

Isn't every subjective experience, almost by definition, unable to be tested scientifically?

We can objectively measure someone's brain activity during sleep, but we can't really measure their subjective experience. Implying that everything made up of subjective experience (like consciousness) can't be measured. Which also implies it can't be proven by scientific means. So in response to the GP comment, I'm not sure we can "know you're awake" (in the scientific sense, at least).


Yes, exactly, that's the point I'm getting at. We experience "life" through our senses, and our senses can be fooled. Even measuring brain activity requires a subjective level of "trust" that we're seeing a real machine that's taking real measurements, rather than a simulation of a machine. We can look for glitches in the matrix, but absence of evidence isn't evidence of absence.

It's wildly impractical to live your life like that, but at the end of the day we just don't know and probably can't know.


I'm pretty sure what you're describing is the hard problem of consciousness.


There are tried and true techniques, like checking your watch. When you're dreaming, it will show different times when you check it.

So if you train yourself to check your watch for consistency (in your normal everyday life), your unconscious will continue the practice in your dreams, and you'll notice the inconsistency.


Sorry if it came across that way, it definitely wasn't the intent! I think Sam Harris has some pretty fascinating and accessible discussions on the topic. There's also some interesting neuroscience work that seems to conflict with the common notions of free-will.


oh yeah, totally agree Sam Harris on this is really awesome. I also love Robert Sapolsky's stuff. He's got several great videos on Youtube and his books are awesome as well.


Liking fruit is far from being an automaton.


Can you elaborate? It's not immediately clear to me what you meant. Can not both simple and complex decisions be the artifact of a deterministic process?


Your blender didnt learn survival from you. Yet.


We don't need to bring humans we can bring some sort of fungus and eventually it will evolve into humans over billions of years.


they've probably already done that to us here on earth


Since it's heavier than Earth, what about the rocket equation? Colonizing it may mean the inhabitants could never leave it.


We're not getting to a planet 100 light years away with chemical rockets so presumably the future inhabitants will be able to use high efficiency rockets to leave it.


I don’t think interstellar travel necessarily implies much better tech than we currently have. I mean, Project Orion style nuke-powered spaceships can get you there in a lifetime but unless you wanna nuke your colony whenever someone needs to leave you still might be stuck on the surface.


What? A nuke in space will have very little impact on a planet. A nuke on a planet doesn't have much impact on the planet either: see all the tests done on earth.


It's a non-trivial number of nukes on every single launch. If it becomes popular, it will have a very noticeable effect on a planet.

Nuclear propulsion isn't the only alternative we have for reaching low orbits. Land-powered rockets are probably much better, and there is always the odd high-elevation rail or space elevator (but those get bad fast on large planets).


There are non-rocket ways to space, like a catapult or maglev accelerator. Or ways to assist the rocket outside the rocket equation, like a spaceplane launch platform. Or even Project Orion nuclear explosion propulsion. (Which is subject to the rocket equation, but with nuclear rather than chemical fuel for a much higher multiplier of energy per mass.)


I'm skeptical a catapult could ever work in an atmosphere as thick as Earth's. The drag would be incredible.


It'd just be 13 km/s to low orbit (or 19 km/s to escape), which isn't really that much for small payloads -- New Horizons had a total of 17 km/s delta-v. You don't even need to look at space elevators or fission or fusion launch systems, all of which are probably viable on first principles.


That orbit or escape velocity really is that much. The rocket equation is exponential, such that even a small change in the required speed means a large change in requirements. The difference between Earth's escape velocity of 11 km/s and this planet's of 19 is actually quite huge. Imagine you build an 11 km/s rocket as you would on Earth... to get it off this other planet, first you have to accelerate that rocket and all its fuel to 8 km/s.

The rocket equation is Δv = Ve ln (m0 / m1), where Ve is exhaust velocity, m0 is payload mass, m1 is mass including fuel. To get 19/11 as much Δv, you need a fuel/mass ratio of e^(19/11) = 5.6 times greater.


So the distance would be like a weekend getaway when it comes to space travel.


Let's gooo!


https://arxiv.org/abs/2208.06333

("TOI-1452 b: SPIRou and TESS reveal a super-Earth in a temperate orbit transiting an M4 dwarf")


This is both exciting and somewhat disappointing. It sounds like the water is so deep that it's probably solid ice (due to the intense pressure) before you get to a rocky core. Life on earth needs nutrients extracted from the rocks. If life formed on this planet, any non-buoyant corpse would sink to the bottom and disappear forever. That is to say, it would almost certainly die out very quickly from lack of nutrition.


A lot of minerals dissolve in water. Without oxygen in the air (like here, before those nasty cyanobacteria released a lot of oxygen) you can get also iron salts disolved in the oceans. https://en.wikipedia.org/wiki/Great_Oxidation_Event#Geologic...

Also, if there are volcanos, they will create plumes dirty of hot water with a lot of disolved things. Something like https://en.wikipedia.org/wiki/Hydrothermal_vent

And you may even have some floating islands made of pumice https://en.wikipedia.org/wiki/Pumice_raft


You might have tiny pockets of life around undersea volcanic vents.


If we're collecting scifi references to water planets, "Neptune's Brood" by Charlie Stross features a very large water world, and the problems of certain minerals (like uranium) dissolved in the oceans. Also the fun things that happens to ice under extreme pressure.


I am surprised more cryptocurrency people do not read Stross. His books feature many speculative examples of crypto backed transactions.

Long live robo kitty!


Reminds me of the "mountains" scene, from Interstellar.

https://youtu.be/4Hf_XkgE1d0?t=90


Based on those observations, the exoplanet appears to be about 70% larger than Earth with just five times its mass. That means it’s less dense than Earth

Seems like a rather large leap to go from that to "it's a water world", at least in these days where we get a "this new exoplanet may be covered in water!" headline every few months.


1.7^3= 4.913. So even if 1.7x large just means radius, if it has 5x the mass that would still make it MORE dense than earth right?


I guess that "about" is doing a lot of work here. Like maybe it's 1.74^3.


Not necessarily. We understand lots of the underlying orbital physics and know from stellar lifecycles how much of each element to expect. From there you can run the math on radius and density and only be left with so many possibilities of what the thing is made of. It’s not certainly water, just one of the likely possibilities. An interesting hypothesis that could actually be tested by atmospheric spectroscopy using Webb.


So its a droplet, were a small moony core tumbles around in the crushing depths?


Someone’s would have to do the math on the core pressure, but likely there would be an ice mantle around a rocky core and possibly a supercritical layer.

https://en.m.wikipedia.org/wiki/Phase_diagram#/media/File%3A...


Imagine lifing on such a world. Ice plates are the only spot to create long lasting structures. Iron is more worth then gold. Meteorites create food frenzies and scavanger hunts. Electrolysis of metals from water is the only way to create a industrial base.


A potentially worthy target for some atmospheric spectroscopy from JWST?


They say as much in the abstract:

> The water world candidate TOI-1452 b is a prime target for future atmospheric characterization with JWST, featuring a Transmission Spectroscopy Metric similar to other well-known temperate small planets such as LHS 1140 b and K2-18 b. The system is located near Webb's northern Continuous Viewing Zone, implying that it can be followed at almost any moment of the year.


That’s fascinating.

> As soon as we can, we will book time on Webb to observe this strange and wonderful world.

How does that work? Is there a hotline you call to book time? Is it free or paid? How is the instrument not booked solid for the next few years?



Interesting read, thanks.


To give you an idea, Hubble Space Telescope observation proposals look like this <https://www.stsci.edu/hst/phase2-public/16642.pdf> and <https://www.stsci.edu/hst/phase2-public/16701.pdf> (chosen because these two are what the HST has been doing in the couple of hours before I typed this). The ABSTRACT sections are probably the parts most of interest to you.

PS: <https://spacetelescopelive.org/latest> might also be of interest over time, as that will eventually report what Webb is looking at.


Getting flashbacks to the sci-fi short story "Grenville's Planet". First contact may not go very well.


Knowing that the planet exists and doing its own thing right now, exotic weather patterns and all is amazing


You mean, existed 100 years ago?


Url changed from https://www.freethink.com/space/ocean-planet, which points to this.


As soon as I hear "light years" things start sounding a lot like religion.


In what way? It’s a simple measure of distance talking about directly observable objects.


Are water worlds even possible around flare stars?


We should stop talking about it and just go.... I'm busy that day though, who wants my place ...


They already know about us.


Only 83 days at warp 6.2, the standard cruising speed for an Intrepid-class starship (or 7.13 days at warp 9.975, maximum sustainable speed for the same ship).


Warp factor 1 is the speed of light. Accelerating safely to the speed of light at a constant 1G acceleration would take 354 days. After that, you would arrive instantaneously no matter where or how far since time stops for you once you reach the speed of light.

https://setiathome.berkeley.edu/forum_thread.php?id=34381#:~....


I wish the script writers had been more self-consistent.

100 ly in 7.13 days would’ve had them home in 13.6 years even without shenanigans. (The warp speed graph I saw suggested more like 7 years, which is even worse for the fundamental plot contrivance of the show).


How long would it have taken to warp to the Gamma Quadrant wormhole I wonder?


I might be able to best that, if Skippy would reprogram a wormhole in the neighborhood.


That may not work. I think the wormhole controller AIs are getting pretty tired of his antics by now.


see you there!


Technically second planet covered in liquid water... they clearly forgot about Earth


Earth is not an exoplanet, it is merely a planet.


Is it an endo or a mesoplanet?


"merely a planet", it's sad that the thing that gives everything life and beauty and wonder can be so easily dismissed nowadays...


Only planet with Life. I sometimes wish people ponder on that for some time. Maybe they will have a new found respect for this planet like I did. Took me a while but when I fully grasped the concept of Life few years back and read and saw all the life less rocks in our solar system it changed the way I look at things. Still amazes me when I think about it.


I only find it amazing the way any other low probability event would be amazing. Nothing more. Like finding a collision between two GUIDs or something


Only planet with life based on what? We haven't been to other planets.


Only planet known to harbor life. Life, at least single celled life, may be fairly common out there but we can't be sure.


You can't be serious. By definition exoplanets are planets outside our solar system.

If you want to be romantic about it, feel free to consider the hunt for exoplanets a challenge to confirm that there is no planet equal to Earth.


You're either misreading every comment intentionally, or really dense.




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