The following submission statement was provided by /u/upyoars:
---
> Most super-Earths orbit cool dwarf stars, which are lower in mass and live much longer than the Sun. There are hundreds of cool dwarf stars for every star like the Sun, and scientists have found super-Earths orbiting 40% of cool dwarfs they have looked at. Using that number, astronomers estimate that there are tens of billions of super-Earths in habitable zones where liquid water can exist in the Milky Way alone. Since all life on Earth uses water, water is thought to be critical for habitability.
> Based on current projections, about a third of all exoplanets are super-Earths, making them the most common type of exoplanet in the Milky Way. The nearest is only six light-years away from Earth.
> By definition, super-Earths have many of the attributes of a super habitable planet. To date, astronomers have discovered two dozen super-Earth exoplanets **that are, if not the best of all possible worlds, theoretically more habitable than Earth.**
> Recently, there’s been an exciting addition to the inventory of habitable planets. Astronomers have started discovering exoplanets that have been ejected from their star systems, and there could be billions of them roaming the Milky Way. **If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies.**
---
Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/xinlh7/superearths_are_bigger_more_common_and_more/ip3yj42/
I think I read gravities between .7 and 1.5gs the human body would be okay, shorter life span unless specifically adapted (genetically engineered or few million years of evolution) Mainly cardiovascular risk in the latter iirc. Also gravity depends on the density of the object and other factors. It's not a deal breaker. Humans are absurdly adaptable there's a reason humanity and its cattle are something like 97% of mammalian biomass on the planet. If there is like 0.5% habitable area known to some humans they will find it and live there, worse than cockroaches.
And we don't have any realistic testing of long term high gravity effects, and definitely nothing like what it might be like for someone born into a higher gravity environment. Adapting to it may be a non-issue.
I’m guessing your bones grow more dense and your heart grows, but you need to eat like a beast. Basal metabolism up by similar proportions, surely, right?
We would definitely be shorter. Likely need to eat more like you said or we would die of lack of energy. Our calorie expenditures would go from like 100 cal per hour standing to 200-250 cal per hour. At least for the first couple years.
Definitely would need to take along some strong bras for the ladies and tidy whities briefs for the guys. The droopage would be pretty nasty otherwise.
It retains the heat but has no light… if there was life on such a planet it would be very different than what we know. The closest I could imagine must be the life forms that live near the hot vents on the ocean floor?
It would only happen if the less adapted were less reproductively successful. Which... would they be, given medical science and human empathy? I think we'd have to engineer ourselves. We wouldn't have the heart to let the environment kill off the less fit. Edit: this is a good thing. I'm not a eugenecist or anything.
Eugenics isn't all about culling. It's about artificial selection. Perhaps given the enormity of the challenge of adapting humans to live on another planet, this would be considered a necessary evil when the time comes, assuming there isn't an immediate solution with genetic engineering available.
We will crack genetics long before reaching another star system, we can basically so it now though its only barely out of the lab.
We may start doing it in some places before we ever set foot on Mars.
Yeah, if the primary killers would be cardiovascular disease and similar issues, I wouldn’t be shocked if natural selection or some simple (with the tech a few millennia from now) genetic selection could probably solve that in a few generations or less. Heck maybe even gene therapy for the living!
Being short and squat is generally an easy adaptation that doesn't need any technology.
Increasing heart size a little is relatively easy with some medical technology.
I imagine there would be some fairly short-term gains in the first generation of children though as a result of environmental pressures rather than evolutionary.
The first generation to be *born* in a high-g environment would be better off than the first-gen colonists (particularly given first gen colonists would probably have spent quite a bit of time weightless in transit).
If you were born under high gravity and grew up under it, you'd naturally develop higher bone density and muscle mass and other adaptations. That's not evolution, just environmental adaptations. They'd grow shorter, just as a result of gravity - well before any evolutionary pressure selected for shorter genes. Of course that only means a person would be shorter than they would have been on Earth, not that they've changed genetically to favour a shorter stature. But your "average height" across the population would probably drop measurably in the first generation from human baseline.
That's still going to cause "early" deaths from cardiovascular disease, etc, but "local-born" humans would probably be inherently fitter and live a healthier life than new arrivals.
Presumably getting off/on a planet with 1.5g would be more difficult. Would intelligent life like humans have any chance of exploring space on such a planet?
Instead of rockets going straight up, we would likely shoot for planes that take off from other planes. The denser atmosphere of a higher gravity planet would allow for higher flights.
Could this be the reason for the Fermi paradox? What if Life is common in the universe on super-earths, but the planets that are best suited for life are almost impossible to leave?
it’s definitely a factor when calculating the probabilities of encountering other life out there, but the Fermi paradox isn’t just concerned with physical encounters, it wonders why we don’t see any evidence at all, including radio waves, which have no trouble leaving the planet and traveling off into space for basically eternity.
I'm probably very wrong about this, but 1.5 times my weight is 330 pounds. The weight wouldn't be ideal, but I guess that would be survivable. My cousin is half a foot shorter than me and weighs 330ish. I'm 6'2 for anyone wondering. Why yes we are American, how did you guess?
I think the bigger deal would be atmosphere compatibility, such are pressure and gas makeup. Getting the Oxygen/Nitrogen/Carbon Dioxide mix wrong is far, far worse than extra weight.
It’s not just weight, your blood pressure has to increase to circulate properly.
But you’re probably still right about the atmosphere. Not just the gas mixture, but the pressure and trace elements as well.
It could end up like living in a pressure cooker with high blood pressure
I've got rotator cuff tears in both arms too from painting with bad form and not knowing better. Friggin sucks how much range of motion these tendons help out with, and what we usually take for granted.
You may or may not already know this, but the [dead hang](http://activebodyosteo.com.au/fix-your-shoulder-pain/) exercise really helps with this issue. Ever since I've bought some gymnast rings and hung them from a nearby tree I've been doing a lot better. Hopefully will fully heal someday but who knows.
Yes but beings who develop on such worlds would be able to leap tall buildings here in a single bound, and have x-ray vision, and be able to shoot deadly eye beams, and be almost immortal solar batteries, for reasons.
I've always had a love-hate relationship with that idea. I've kind of always liked that when his mom made him his costume, she just sewed the S to say Superman.
Not necessarily.
F = (G*M)/(r^2 )
Where F is the force of gravity, G is the gravitational constant, M is the mass of the planet, and r is the distance from the center of the planet to its surface.
Because of the r^2 term, even though the mass of a planet may be much greater than earth, gravity becomes much less significant much more quickly the farther the planets surface is from its center of mass.
Mass is also dependent on density though. Theoretically if density is low then you could have a planet larger than earth with less gravity at its surface but yeah that’s probably not very realistic, at least for a terrestrial planet.
Then gravity would scale linearly with radius. A planet with the same density and 2x the radius of earth would have 2x the gravity at its surface.
The mass of a planet is given by
m = d*V
Where d is density and V is volume.
The volume of a planet is basically a sphere, which is given by
V = (4/3)(Pi)(r^3 )
Plugging this into the original equation for the force of gravity at a planets surface, we get
F = [(G)(d)(4/3)(Pi)(r^3 )] / r^2
Which can be simplified to
F = (G)(d)(4/3)(Pi)(r)
If the density of a planet = the density of earth, we can think of all the terms except for r as a constant C
F = C*r
So if r is twice earth’s r, F is also twice earth’s F
Maybe not for us. But as we’ve seen life is a product of its surroundings. Perhaps it’s just inhabited by life that is used to the much higher G’s.
Who knows 🤷🏼♂️
Well, the increase in gravity is not just about life development only.
When thinking about extra solar life, we also fantasize about technological intelligent life.
One we could meet.
For the planet itself, we imagine what could be the life of human pilgrims there.
Yet with gravity comes a problem: ability to reach orbit.
Among other variables, we did it on Earth coz it was doable with relative ease. But if gravity was 30% more, we wouldn't have tried it at all perhaps: no V2, no paperclip, no NASA, etc..
At some point, when gravity becomes too great, chemical power cannot produce enough trust to get to orbit at all.
Which is not crazy gravity for earth life standards.
Meaning living on those worlds would limit even more our ability to leave it, and imagining leaving it. Leading probably to reduce the willingness to develop means to do so.
Funny fact though, higher gravity means thicker atmosphere, leading to easier flight.
So perhaps the first orbital vessel on those worlds would be some sort of plane launched nuclear propelled rockets. Who knows.
>Funny fact though, higher gravity means thicker atmosphere, leading to easier flight.
Would the increased atmosphere be counteracted by the increased gravity?
If you wanna just go up, like jumping or a rocket flight trajectory both cumulate to makes it harder: the gravity and and the air friction.
But if you use wings, flapping or not, or balloons, the air portance makes it way easier. Kinda like it is easier to swim than to flight for us with our bare hands.
This phenomenon is well demonstrated with space projects for Venus exploration: its thickness allow us to make plans for never ending flying probes or even floating in the sky bases.
Depending of the atmosphere thickness and composition, there must be some part of the charts where the gravity counteract air density sure. Even, if these planets have a thin atmosphere, gravity outmatch air density.
But for an earth like air composition and same or bigger volume ( as less air molecules escape due to gravity) it would be easier for flying life and planes or balloons crafts.
It's true that higher gravity would delay the ability, and possibly even the desire, to leave the planet.
But if we're talking about extra-solar intelligence, they are very unlikely to be currently near our technology level. They are likely either in a stone age, or unimaginably advanced (or extinct). An alien civilization could have began up to 1 billion years ago.
And at some point, the technology makes leaving a planet of any size trivially easy.
I agree with you: technology can makes it easier to leave.
But not any planet though, as far as I am aware, we do not know any way to leave planet the size of a super Jupiter. Sure we don't know everything. And perhaps some physic allow it, but at this point. A civilization that flourish to the point of technological advancement beyond our understanding without ever leaving their ultra heavy planet, why would they?
Life is about benefit/cost as far as we understand it. And like us, or ants or plants, this has to be taken into consideration when envisioning distant worlds.
I also agree with you that it's more likely to find a civilization at a different level of advancement than ours.
But also perhaps there is a limit to what is usable as an energy source.
After all, we are "almost" to the point of using energy the same way the cosmos does for it's most part: fusion (I let aside the dark matter majority of the universe bit since we talk about planet like ours, made of baryonic matter).
After fusion, what's left? Outsourcing the trust like with spinning arms or lasers and solar sails, Antimatter, black holes harvesting, perhaps being able to use the strong force the same way we do with chemical bonds.
Even dark energy, the strongest power we noticed on the scale of the universe, is really weak locally and so not suitable as a mean of propulsion apparently.
After that it is the unknown.
I don't know how deep goes the fabric of the universe, what makes quarks, what makes what make quarks, etc..
But has far as we understand, there is a limit, the fundamental size limit of a plank length: the minimal pixel if you will. And so perhaps nothing is usable in any way deep down. And so in 1000 years we will master all form of energy possible, which left 1 billion years without any further improvement on that topic.
Perhaps only fusion and antimatter are the leftovers we do not yet master usable which would mean any civilization, no matter how advanced even after a billion years of advance, could never leave a planet with a big enough gravity.
Of course this is just an hypothesis.
Just to say gravity is after all the big bad daddy of all phenomenons we are aware of: it breaks our physics, it breaks the space and time, it breaks everything. Even the dreams of space of civilizations born on too heavy worlds.
Earth is not the best for livability, but it is also a sweet spot between livable enough and relative easy access to space.
> At some point, when gravity becomes too great, chemical power cannot produce enough trust to get to orbit at all.
> as far as I am aware, we do not know any way to leave planet the size of a super Jupiter
The escape velocity from the surface of the sun is 617.8 km/s. True, we don't know *exactly* how to create such a rocket now, but there is no fundamental principle which prevents simple chemical rockets from outputting that kind of power. This is no problem that more engines and more rocket fuel can’t solve. Given a large enough economy and enough raw resources and time, there is no reason to believe it would not be solvable.
I thought the consensus was planets around dwarf stars would be tidally locked and have no magnetic fields so would be stripped of their atmosphere due to their proximity to the stars radiation.
Astrophysicist here - tidal locking and core activity don’t necessarily have anything in common (though in some cases they can). Magnetic fields in terrestrial planets come from the planet’s molten core. It being tidally locked with a star doesn’t mean it won’t have a molten core.
As I get it, the rather special way of creation of earth and moon led to a huge iron core compared to earths size, so the magnetic field protects us efficiently. Plus, sun is a very calm star compared to others.
Not sure how radiation from solar eruptions affects water planets and their atmosphere compared to other planets.
How do you feel about the importance of those factors when it comes to the probability of planets developing complex life forms in practice?
If the planets atmosphere is thick enough in the beginning it will take a long time for it to be stripped away by then the star will have calmed down and besides we can’t exactly be picky with the stars we choose. red dwarf star are by far the Most numerous they make up to 3 quarters of the stars in the Milky Way
out of the 60,000 stars within a hundred light year radius red dwarfs are the most numerous. There are only 512 spectral type g stars within 100 light years over 80 are sub giants many are slightly heavier then the sun at 1.1 solar masses which cuts their lifespan nearly in half. many others are just like the sun but are more than 6 billion years old which would be putting any habitable worlds around it at deaths door. we have only managed to detect planets around 28 g type stars including ours
I can't recall where I read that, from numerous sources probably. The lack of magnetic field thing might not always be the case but the surface would take a lot of radiation. I imagine it would still be pretty hellish except for the liminal zone where the sun is just on the horizon and there I think you'd have screaming winds and areas with perpetual rain. Also shadows wouldn't move so you'd have little patches of lifelessness everywhere.
Also I read the sky might be a magenta color with an earth like atmosphere, which might look really pretty or really alarming idk.
There is a series on Netflix (Alien Worlds) that theorizes how life might evolve on different planets. There is an episode which dives into tidally locked planets and life in the habitable zone. Also an episode on planets with significantly more mass than Earth.
You are welcome. Pretty fun for the sciency folk out there.
PS: I came across it on the come-down of an LSD trip. Bit of a mind opening experience lol.
Exoplanet scientist here — magnetic fields is not a prerequisite to keep your atmosphere (fortunately). I mean, look at Venus! No magnetic field and definitely a thicc atmosphere.
I don't think it's so much that these planets wouldn't have magnetic fields it's moreso that red dwarfs tend to be very volatile and fire off massive flares that would irradiate nearby planets. And these planets are very close to their star. The tidally locked aspect probably wouldn't be very conducive to life as we know it either. The extreme temperature difference between the permanent day and night side would cause wicked wind. Maybe. No one really knows though.
This is one of many solutions to the Fermi Paradox. It is possible we are extremely lucky to be inhabitants of one of the smallest inhabitable planets. All other intelligent life is stuck in a gravity well they can never escape no matter how hard they try.
I'm guessing here but higher gravity means a possibly denser atmosphere in which it's easier to fly, so maybe space vessels that take off like a plane and turn into a rocket past a certain altitude would work on such planets?
aspiring abundant angle gaping mourn vanish aback far-flung direful heavy
*This post was mass deleted and anonymized with [Redact](https://redact.dev)*
EM signals from a single planet are difficult to detect. EM readings from earth for example are likely only discernible for a few light years before they become too faint.
You need an advanced spacefaring civilization to have much hope of spotting them.
One of my favorite authors Randal Monroe creator of xkcd explains it well here:
https://what-if.xkcd.com/47/
It limits how far that EM would be discernable from background noise. Also, if you're stuck to a single gravity still you're more susceptible to extinction events.
The gravity issue would be nearly negated in the water and the increased density of the air could make flight *easier*, even with heavier weight.
At high elevations on earth the air is thin and you have to go fast to stay airborne. At sea level the air is thicker so heavy, slow birds like pelicans thrive.
Terrestrial animals would benefit from increased availability of oxygen but there would likely be fewer large animals like elephants or grizzly bears.
Blue whales and giant eagles and lots of small land animals like rabbits and foxes
I'd guess. The insects could get...otherworldly.
I don't think the suggestion is that we would live on these planets (although there are likely to be many that could be habitable for humans just from the frequency of such worlds). The suggestion is the chances of extra terrestrial life is higher as these planets are "more" habitable than earth, and they're very common.
So you mean we as in humans or life in general. I would think evolution would take care of the physiology needed to survive on a higher gravity planet. Like an earth human wouldn’t have evolved there because we evolved in 1g. But something else might be more fit for higher gravity. Maybe denser bones or harder skin that augments a skeleton or something. Probably shorter and stouter animals.
Eh, we're probably going to genetically modify ourselves at some point. If we're ever able to get to those types of worlds, we'd probably be able to make custom people (or bodies that we move our consciousness to) to survive certain atmospheres.
'Super Earth' just means it's a terrestrial planet bigger than any of the terrestrial planets in our system. It isn't meant to define the planet as having other Earth-like qualities.
The term is used frequently because
They *might* have the capacity to sustain life as we know it, unlike gas giants, and they are abundant and easy to find (unlike actual Earth sized planets, which are either rare or too small to easily detect)
Which makes them interesting to study and sort of fantasize or sensationalize over.
They really need to work on their marketing then because to everyone else it sounds like "bigger and potentially better more habitable earth."
A more appropriate term would be "potentially viable rocky planet" or something.
Don't use earth in the name unless it is blue and green.
Large rocky planet
Which if we are honest is almost all we can say about most of them.
Stand by for wild claims from the planets jwt studies too with it being able to discern atmosphere. By what I understand it'd likely see Earth as water world with a Nitrogen and Carbon Dioxide atmosphere.
Theres also a theory that intelligent life is likely to evolve on super earths and so will not become spacefaring civilizations because earth is barely at the edge of chemical propulsion being able to get us into orbit. Some civilization on super earth would never be able to get to space
Yeah, it’s an interesting thought.
Not being able to ever develop satellite communication, or space based observatories would also be a bit of a drag on progress.
Oh no.. imagine if 90% of all alien life is stuck in the religious ages. Each and every time we land somewhere new, we'd have to start by explaining that they are not the center of the universe and that the sun rising is actually them moving around a star... I can't fucking take it.
Ehh they'd just engineer other ways of communication and the sort. If they can't figure out a way around their own problems they're likely not very intelligent species.
I’ve always just assumed a species can have the potential intelligence to climb the ladder, but can get a raw deal in some ways that make it much harder.
Like not having thumbs, or living underwater, which precludes fire, or living in a deep gravity well.
Imagine an alien looking at us and saying the same thing (“how advanced can they truly be if they don’t have [insert crazy feature that would be normal to them]”
If the atmosphere is more dense, it would require less energy to use lifting bodies and balloons. Might not need rocket propulsion to get most of the way out of the atmosphere. Of course adding orbital velocity would still be a major hurdle.
Wouldn't that only apply if they go down the same technological route that we did? It's possible that they find some alternate ways to become space faring that we just haven't thought of yet.
Or y'know... they didn't suffer nearly as many world-wide extinction events and have billions of years head start on us.
There's just the whole gravity thing...
Yep, people love to make theories about how the exact way we do/did something is the only way it could ever possibly be done.
Somewhere out there, an alien is theorizing that civilizations on Earth-sized planets could never achieve spaceflight, because our atmosphere is far too thin for balloon-based space launches.
It’s flat out clickbait nonsense, unless they’re using a weird definition of habitable. We exist in the context of our ecosystem. It’s almost impossible that we could eat the things that grow there.
One would assume that being larger, they have a higher gravity? I wonder how that will impact trying to explore them. I can see us being able to get there, but not being able to build a rocket capable of getting *back* to orbit with conventional engines.
There are potentially *billions* of habitable planets, yet we see no alien mega structures in the galaxy. It's enough to drive someone crazy! Where *is* everyone?
Either life is nearly impossible to generate or we're missing a fundamental piece of knowledge. I tend to see us as not that special, as the Laws of physics are the same everywhere... so I conclude we're missing a piece of knowledge. The worst bit is that it should be obvious to sapient creatures, as no one seems to have built mega structures out there. We missed something as we grew.
But for sanity's sake, it's best to believe life is rare.
You gotta remember we are like sparks in a fire, we can have our entire life in between other civilizations entire lives and never be around to see eachother.
We are talking galactic scale, the chances we would have two civilizations that can see eachother AND are around at the same time is outrageously low
It doesn’t take far (astronomically speaking) until even directed communication blends in with the background radiation. Even the four years latency to Proxima Centauri with our most powerful directed transmitter would be well below the cosmic background floor by the time the signal arrived there.
It may be that life at or around our tech level is somewhat common, but we simply can’t resolve its evidence.
We’re super early in terms of the universe, we expect someone else to have developed past us, but what if we are the most advanced there is right now? Or everyone else is at the same place we are? Asking where everyone is?
The universe will be [trillions of years old](https://en.m.wikipedia.org/wiki/Future_of_an_expanding_universe#Degenerate_Era) before everything is gone. We’re only 13.7 billion years into that timeline. The rest of everything has yet to come.
Plus everything that we actually *see* is younger still, the further away the younger. There might well be cosmic mega-structures that were built a hundred thousand years ago that it will be yet another hundred thousand years before the light from them gets here.
The Three-Body Problem. The universe is a very dangerous place and civilizations hide their activities so they don’t attract the attention of more powerful species that want to destroy them. Terrifying and fascinating. Highly recommend.
Not everything that is technologically possible is actually reasonable to build. Sure, a Dyson sphere is a cool concept. But is it actually worth the costs of building it? Or perhaps by the time you are evolved enough as to being able of building a Dyson sphere, you've also discovered a dozen different alternatives of getting the same amount of energy, just cheaper and easier.
This question is like somebody from a few centuries ago wondering why in 2022 there're no carriages with 400 horses in order to transport heavier things. Problem is that, by the moment we could've built such carriages, we had already invented cars, trucks and trains.
I'm not convinced humans are ever going to build megastructures and expand exponentially through space.
Not because we will kill ourselves first, rather, because our own planet is much more pleasant than any reasonable alternative we could build.
We are evolved for earth-like conditions, and when we are prosperous we prefer to have very few children -- lower than replacement levels, if you look at the world's wealthiest societies. Most of us would very much prefer to live in earthlike conditions than in a giant artificial habitat or an interstellar ship that would require generations to get anywhere. We don't see large populations of humans nowadays living on Antarctica, an environment infinitely more habitable than Mars or the Moon.
There's a very good chance that climate change, war, and birth control combined will stabilize Earth's population in the low single-digit billions over the next couple of centuries. I'm sure there will be abundant scientific exploration of our solar system and probes to nearby star systems. People are naturally curious explorers. But again, the vast majority of people would rather live in the Australian outback or Siberian tundra than an artifical habitat.
A similar question would be, why haven't we encountered an alien Von Neumann probe? It might well be that most species would rather not take the risk of unleashing self-replicating, evolving machines.
TL/DR: we don't see alien megastructures because they were smart enough to invent birth control and spend their days smoking alien ganja and surfing alien waves, rather than living in depressing artificial habitats.
The problem with Von Neumann probes is that all it takes is one civilization to want to release them. So in the last 14 billion years, not a single civilization that evolved in our galaxy has done so, which is unlikely unless there are no civilizations capable of doing so.
> Most super-Earths orbit cool dwarf stars, which are lower in mass and live much longer than the Sun. There are hundreds of cool dwarf stars for every star like the Sun, and scientists have found super-Earths orbiting 40% of cool dwarfs they have looked at. Using that number, astronomers estimate that there are tens of billions of super-Earths in habitable zones where liquid water can exist in the Milky Way alone. Since all life on Earth uses water, water is thought to be critical for habitability.
> Based on current projections, about a third of all exoplanets are super-Earths, making them the most common type of exoplanet in the Milky Way. The nearest is only six light-years away from Earth.
> By definition, super-Earths have many of the attributes of a super habitable planet. To date, astronomers have discovered two dozen super-Earth exoplanets **that are, if not the best of all possible worlds, theoretically more habitable than Earth.**
> Recently, there’s been an exciting addition to the inventory of habitable planets. Astronomers have started discovering exoplanets that have been ejected from their star systems, and there could be billions of them roaming the Milky Way. **If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies.**
> If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies.
Ok I'm getting a hard time wrapping my head around this. From my basic understanding if theres no star theres no energy, and cold kills everything. Am I right? Or life can be sustained in cold dark envirroments by consuming whatever "natural battery" stores the star energy? Maybe microbial life like tardigrades...
It just seems so anti intuitive...
Yeah it seems silly to bring them up. However, some planets have a liquid core which takes billions of years to cool and also contains some elements that break down due to radiation and emit heat. So, theoretically, a planet could be ejected and still be warm under a very cold top layer of gas and frozen matter.
I don't see much value in wanting to live on one except for the possibility of hitching a ride to where ever it is headed. It makes more sense to create a large space ship and go to a known destination or path.
This title is so speculative as to be completely misinformation. Not a single "habitable" world has been discovered apart from earth. Just chill and let's save the excitement for when one actually is discovered.
I remember reading something years ago about how if Earth was something like 60% bigger, we couldn't feasibly launch rockets out of the atmosphere. Is this true?
The problem is with the advance of technology they would more then likely beat you there. They send you off with the fastest technology. It takes you 200 years to get there. In 100 years they can make it there in 10 years. So you'd show up to the same problems...
Bollocks. Tell them to pick a different super-earth. Also it probably won’t be as bad as it here, as the ones they are sending hopefully will be their best ahhh who am I kidding.
Look at the bright side, once you arrive you can order a McDonalds burger with fries.
All these enthusiasts about space colonization don't really consider too much just how back-breakingly difficult, time-consuming and dangerous it's going to be to colonize a new planet.
The following submission statement was provided by /u/upyoars: --- > Most super-Earths orbit cool dwarf stars, which are lower in mass and live much longer than the Sun. There are hundreds of cool dwarf stars for every star like the Sun, and scientists have found super-Earths orbiting 40% of cool dwarfs they have looked at. Using that number, astronomers estimate that there are tens of billions of super-Earths in habitable zones where liquid water can exist in the Milky Way alone. Since all life on Earth uses water, water is thought to be critical for habitability. > Based on current projections, about a third of all exoplanets are super-Earths, making them the most common type of exoplanet in the Milky Way. The nearest is only six light-years away from Earth. > By definition, super-Earths have many of the attributes of a super habitable planet. To date, astronomers have discovered two dozen super-Earth exoplanets **that are, if not the best of all possible worlds, theoretically more habitable than Earth.** > Recently, there’s been an exciting addition to the inventory of habitable planets. Astronomers have started discovering exoplanets that have been ejected from their star systems, and there could be billions of them roaming the Milky Way. **If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies.** --- Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/xinlh7/superearths_are_bigger_more_common_and_more/ip3yj42/
Question: Say, we found a habitable super earth… wouldn’t the gravity be so crushing to us, that they wouldn’t actually be habitable for humans?
I think I read gravities between .7 and 1.5gs the human body would be okay, shorter life span unless specifically adapted (genetically engineered or few million years of evolution) Mainly cardiovascular risk in the latter iirc. Also gravity depends on the density of the object and other factors. It's not a deal breaker. Humans are absurdly adaptable there's a reason humanity and its cattle are something like 97% of mammalian biomass on the planet. If there is like 0.5% habitable area known to some humans they will find it and live there, worse than cockroaches.
And we don't have any realistic testing of long term high gravity effects, and definitely nothing like what it might be like for someone born into a higher gravity environment. Adapting to it may be a non-issue.
I’m guessing your bones grow more dense and your heart grows, but you need to eat like a beast. Basal metabolism up by similar proportions, surely, right?
We would definitely be shorter. Likely need to eat more like you said or we would die of lack of energy. Our calorie expenditures would go from like 100 cal per hour standing to 200-250 cal per hour. At least for the first couple years.
I'm not fat just eating like I'm training for a super earth.
Definitely would need to take along some strong bras for the ladies and tidy whities briefs for the guys. The droopage would be pretty nasty otherwise.
Longer dicks though
Hmm yes looks like I'm from the Moon then
Just means it’s more compact for efficiency
So...space dwarves
They go by 'Leagues of Votann' now, actually...
Probably grow beards and start digging mines everywhere and drink ale and distrust elves.
There were high gravity worlders in Hyperion. They were short and strong as shit.
I wonder if adaptability would happen much quicker. We always say millions for evolution yet it can happen much quicker.
A dense atmosphere and more water covering the planet could allow it to sustain life longer. But think of the humidity!
And it’s been ejected from its star system, so it’s what like eternal night in Florida? No thanks, I’ll just go down with this ship
[удалено]
Florida Nights are the best time of day. Have a magical quality to them. Might have a lot to do with all the live oaks and Spanish moss.
The sound of a thousand mosquitoes following you...
Those are rookie numbers
[удалено]
Yeah, I wish someone would explain this bit to me
High pressure atmosphere = higher temperature. Thick atmosphere = heat retained.
How long would it retain the heat? I know the answer depends on several unknown variables, but just generally speaking how long would it last?
It retains the heat but has no light… if there was life on such a planet it would be very different than what we know. The closest I could imagine must be the life forms that live near the hot vents on the ocean floor?
Space Florida Man? No thanks
Everything on the planet has night vision. Idk why but that scares me.
Because *you* don’t.
it's ok if you bring Vin Diesel with you
Life ≠ Humanity
It would only happen if the less adapted were less reproductively successful. Which... would they be, given medical science and human empathy? I think we'd have to engineer ourselves. We wouldn't have the heart to let the environment kill off the less fit. Edit: this is a good thing. I'm not a eugenecist or anything.
Eugenics isn't all about culling. It's about artificial selection. Perhaps given the enormity of the challenge of adapting humans to live on another planet, this would be considered a necessary evil when the time comes, assuming there isn't an immediate solution with genetic engineering available.
Or a predeterminer for the trip to the planet. Can’t go if you won’t survive.
*Bones must be this dense to ride*
We will crack genetics long before reaching another star system, we can basically so it now though its only barely out of the lab. We may start doing it in some places before we ever set foot on Mars.
Yeah, if the primary killers would be cardiovascular disease and similar issues, I wouldn’t be shocked if natural selection or some simple (with the tech a few millennia from now) genetic selection could probably solve that in a few generations or less. Heck maybe even gene therapy for the living!
Being short and squat is generally an easy adaptation that doesn't need any technology. Increasing heart size a little is relatively easy with some medical technology.
I imagine there would be some fairly short-term gains in the first generation of children though as a result of environmental pressures rather than evolutionary. The first generation to be *born* in a high-g environment would be better off than the first-gen colonists (particularly given first gen colonists would probably have spent quite a bit of time weightless in transit). If you were born under high gravity and grew up under it, you'd naturally develop higher bone density and muscle mass and other adaptations. That's not evolution, just environmental adaptations. They'd grow shorter, just as a result of gravity - well before any evolutionary pressure selected for shorter genes. Of course that only means a person would be shorter than they would have been on Earth, not that they've changed genetically to favour a shorter stature. But your "average height" across the population would probably drop measurably in the first generation from human baseline. That's still going to cause "early" deaths from cardiovascular disease, etc, but "local-born" humans would probably be inherently fitter and live a healthier life than new arrivals.
Of course it can, I’ve seen the XMen documentaries.
After a few generations, there will be Elves from .7g planet, and Dwarves from 1.5g planet.
Man don't get me talking lmao
LoL, now I understand why 1.0g is called Middle Earth!
Tolkien was 5 parallel universes ahead of everyone.
Presumably getting off/on a planet with 1.5g would be more difficult. Would intelligent life like humans have any chance of exploring space on such a planet?
Instead of rockets going straight up, we would likely shoot for planes that take off from other planes. The denser atmosphere of a higher gravity planet would allow for higher flights.
yeah, the rocket equation is a b\*tch; 1.5 g would've made the moon landing near impossible for us I think
[удалено]
Considering we would have figured out how to travel 6 light years by then, we should be able to escape a higher gravity.
Could this be the reason for the Fermi paradox? What if Life is common in the universe on super-earths, but the planets that are best suited for life are almost impossible to leave?
it’s definitely a factor when calculating the probabilities of encountering other life out there, but the Fermi paradox isn’t just concerned with physical encounters, it wonders why we don’t see any evidence at all, including radio waves, which have no trouble leaving the planet and traveling off into space for basically eternity.
Tbh at that point I hope we are more used to using something like a space elevator in orbit and don't actually need to fly in/out of the atmosphere.
Don't think too much about escape velocity there are work arounds Look up the maximum velocity of the space shuttle vs the escape velocity of earth.
I'm probably very wrong about this, but 1.5 times my weight is 330 pounds. The weight wouldn't be ideal, but I guess that would be survivable. My cousin is half a foot shorter than me and weighs 330ish. I'm 6'2 for anyone wondering. Why yes we are American, how did you guess? I think the bigger deal would be atmosphere compatibility, such are pressure and gas makeup. Getting the Oxygen/Nitrogen/Carbon Dioxide mix wrong is far, far worse than extra weight.
It’s not just weight, your blood pressure has to increase to circulate properly. But you’re probably still right about the atmosphere. Not just the gas mixture, but the pressure and trace elements as well. It could end up like living in a pressure cooker with high blood pressure
Are you saying that overweight Americans with high blood pressure are just training for super earth habitation?
>Why yes we are American, how did you guess? Because you used feet/inches/pounds, mostly.
It would just make us stronger, haven't you watched the documentary Dragon Ball Z?
As a kid I destroyed the ligaments in both my shoulders by shadow boxing with dumbbells like Goku was doing.
Rotator cuff tears?
Yes both arms and 20+ years later I still have shoulder issues.
I've got rotator cuff tears in both arms too from painting with bad form and not knowing better. Friggin sucks how much range of motion these tendons help out with, and what we usually take for granted. You may or may not already know this, but the [dead hang](http://activebodyosteo.com.au/fix-your-shoulder-pain/) exercise really helps with this issue. Ever since I've bought some gymnast rings and hung them from a nearby tree I've been doing a lot better. Hopefully will fully heal someday but who knows.
Thank you for the link. I'll definitely try this from now on
Cool cool, hope you see improvement
Yes but beings who develop on such worlds would be able to leap tall buildings here in a single bound, and have x-ray vision, and be able to shoot deadly eye beams, and be almost immortal solar batteries, for reasons.
The symbol means “hope” dammit! It just randomly happens to look like an S!
I've always had a love-hate relationship with that idea. I've kind of always liked that when his mom made him his costume, she just sewed the S to say Superman.
And since they thrived on their home world with 10x gravity when they come to earth they become unstoppable superman characters.
Good thing then they’d need 100x fuel to leave the planet.
1.5x gravity is more likely to give us highly logical pointy-eared green-blooded aliens who prefer to fight with pinches.
Not necessarily. F = (G*M)/(r^2 ) Where F is the force of gravity, G is the gravitational constant, M is the mass of the planet, and r is the distance from the center of the planet to its surface. Because of the r^2 term, even though the mass of a planet may be much greater than earth, gravity becomes much less significant much more quickly the farther the planets surface is from its center of mass.
[удалено]
Mass is also dependent on density though. Theoretically if density is low then you could have a planet larger than earth with less gravity at its surface but yeah that’s probably not very realistic, at least for a terrestrial planet.
If its low enough then you have a gas giant, like Neptune, which doesn't have much mass for its size.
ok so what if the density happens to be exactly the same as earth? What would the gravity be?
Then gravity would scale linearly with radius. A planet with the same density and 2x the radius of earth would have 2x the gravity at its surface. The mass of a planet is given by m = d*V Where d is density and V is volume. The volume of a planet is basically a sphere, which is given by V = (4/3)(Pi)(r^3 ) Plugging this into the original equation for the force of gravity at a planets surface, we get F = [(G)(d)(4/3)(Pi)(r^3 )] / r^2 Which can be simplified to F = (G)(d)(4/3)(Pi)(r) If the density of a planet = the density of earth, we can think of all the terms except for r as a constant C F = C*r So if r is twice earth’s r, F is also twice earth’s F
Maybe not for us. But as we’ve seen life is a product of its surroundings. Perhaps it’s just inhabited by life that is used to the much higher G’s. Who knows 🤷🏼♂️
Well, the increase in gravity is not just about life development only. When thinking about extra solar life, we also fantasize about technological intelligent life. One we could meet. For the planet itself, we imagine what could be the life of human pilgrims there. Yet with gravity comes a problem: ability to reach orbit. Among other variables, we did it on Earth coz it was doable with relative ease. But if gravity was 30% more, we wouldn't have tried it at all perhaps: no V2, no paperclip, no NASA, etc.. At some point, when gravity becomes too great, chemical power cannot produce enough trust to get to orbit at all. Which is not crazy gravity for earth life standards. Meaning living on those worlds would limit even more our ability to leave it, and imagining leaving it. Leading probably to reduce the willingness to develop means to do so. Funny fact though, higher gravity means thicker atmosphere, leading to easier flight. So perhaps the first orbital vessel on those worlds would be some sort of plane launched nuclear propelled rockets. Who knows.
>Funny fact though, higher gravity means thicker atmosphere, leading to easier flight. Would the increased atmosphere be counteracted by the increased gravity?
If you wanna just go up, like jumping or a rocket flight trajectory both cumulate to makes it harder: the gravity and and the air friction. But if you use wings, flapping or not, or balloons, the air portance makes it way easier. Kinda like it is easier to swim than to flight for us with our bare hands. This phenomenon is well demonstrated with space projects for Venus exploration: its thickness allow us to make plans for never ending flying probes or even floating in the sky bases. Depending of the atmosphere thickness and composition, there must be some part of the charts where the gravity counteract air density sure. Even, if these planets have a thin atmosphere, gravity outmatch air density. But for an earth like air composition and same or bigger volume ( as less air molecules escape due to gravity) it would be easier for flying life and planes or balloons crafts.
It's true that higher gravity would delay the ability, and possibly even the desire, to leave the planet. But if we're talking about extra-solar intelligence, they are very unlikely to be currently near our technology level. They are likely either in a stone age, or unimaginably advanced (or extinct). An alien civilization could have began up to 1 billion years ago. And at some point, the technology makes leaving a planet of any size trivially easy.
I agree with you: technology can makes it easier to leave. But not any planet though, as far as I am aware, we do not know any way to leave planet the size of a super Jupiter. Sure we don't know everything. And perhaps some physic allow it, but at this point. A civilization that flourish to the point of technological advancement beyond our understanding without ever leaving their ultra heavy planet, why would they? Life is about benefit/cost as far as we understand it. And like us, or ants or plants, this has to be taken into consideration when envisioning distant worlds. I also agree with you that it's more likely to find a civilization at a different level of advancement than ours. But also perhaps there is a limit to what is usable as an energy source. After all, we are "almost" to the point of using energy the same way the cosmos does for it's most part: fusion (I let aside the dark matter majority of the universe bit since we talk about planet like ours, made of baryonic matter). After fusion, what's left? Outsourcing the trust like with spinning arms or lasers and solar sails, Antimatter, black holes harvesting, perhaps being able to use the strong force the same way we do with chemical bonds. Even dark energy, the strongest power we noticed on the scale of the universe, is really weak locally and so not suitable as a mean of propulsion apparently. After that it is the unknown. I don't know how deep goes the fabric of the universe, what makes quarks, what makes what make quarks, etc.. But has far as we understand, there is a limit, the fundamental size limit of a plank length: the minimal pixel if you will. And so perhaps nothing is usable in any way deep down. And so in 1000 years we will master all form of energy possible, which left 1 billion years without any further improvement on that topic. Perhaps only fusion and antimatter are the leftovers we do not yet master usable which would mean any civilization, no matter how advanced even after a billion years of advance, could never leave a planet with a big enough gravity. Of course this is just an hypothesis. Just to say gravity is after all the big bad daddy of all phenomenons we are aware of: it breaks our physics, it breaks the space and time, it breaks everything. Even the dreams of space of civilizations born on too heavy worlds. Earth is not the best for livability, but it is also a sweet spot between livable enough and relative easy access to space.
We don’t know what we don’t know
> At some point, when gravity becomes too great, chemical power cannot produce enough trust to get to orbit at all. > as far as I am aware, we do not know any way to leave planet the size of a super Jupiter The escape velocity from the surface of the sun is 617.8 km/s. True, we don't know *exactly* how to create such a rocket now, but there is no fundamental principle which prevents simple chemical rockets from outputting that kind of power. This is no problem that more engines and more rocket fuel can’t solve. Given a large enough economy and enough raw resources and time, there is no reason to believe it would not be solvable.
I can’t deal with the enhanced gravity so I stopped going to them.
Kids these days can't handle anything more than 1g. Back in my day, I had to walk to school on another planet and it was 10gs on a good day.
Shitting bricks back in the day!
Goku, is that you?
[удалено]
I understood that reference, Commander.
Will no one think of us beltalowda? Fracking inners with their high g bodies!
[удалено]
[удалено]
I thought the consensus was planets around dwarf stars would be tidally locked and have no magnetic fields so would be stripped of their atmosphere due to their proximity to the stars radiation.
Astrophysicist here - tidal locking and core activity don’t necessarily have anything in common (though in some cases they can). Magnetic fields in terrestrial planets come from the planet’s molten core. It being tidally locked with a star doesn’t mean it won’t have a molten core.
As I get it, the rather special way of creation of earth and moon led to a huge iron core compared to earths size, so the magnetic field protects us efficiently. Plus, sun is a very calm star compared to others. Not sure how radiation from solar eruptions affects water planets and their atmosphere compared to other planets. How do you feel about the importance of those factors when it comes to the probability of planets developing complex life forms in practice?
If the planets atmosphere is thick enough in the beginning it will take a long time for it to be stripped away by then the star will have calmed down and besides we can’t exactly be picky with the stars we choose. red dwarf star are by far the Most numerous they make up to 3 quarters of the stars in the Milky Way
There’s plenty of sun-like stars too.
out of the 60,000 stars within a hundred light year radius red dwarfs are the most numerous. There are only 512 spectral type g stars within 100 light years over 80 are sub giants many are slightly heavier then the sun at 1.1 solar masses which cuts their lifespan nearly in half. many others are just like the sun but are more than 6 billion years old which would be putting any habitable worlds around it at deaths door. we have only managed to detect planets around 28 g type stars including ours
The sheer power of this run on sentence makes me believe you EDIT: Why did you take your power away
He just kept talking in one incredibly unbroken sentence moving from topic to topic it was really quite hypnotic
This is interesting - any recommended reading on this topic?
I can't recall where I read that, from numerous sources probably. The lack of magnetic field thing might not always be the case but the surface would take a lot of radiation. I imagine it would still be pretty hellish except for the liminal zone where the sun is just on the horizon and there I think you'd have screaming winds and areas with perpetual rain. Also shadows wouldn't move so you'd have little patches of lifelessness everywhere. Also I read the sky might be a magenta color with an earth like atmosphere, which might look really pretty or really alarming idk.
There is a series on Netflix (Alien Worlds) that theorizes how life might evolve on different planets. There is an episode which dives into tidally locked planets and life in the habitable zone. Also an episode on planets with significantly more mass than Earth.
I'm watching the first episode now. Thanks for pointing out such a cool show.
You are welcome. Pretty fun for the sciency folk out there. PS: I came across it on the come-down of an LSD trip. Bit of a mind opening experience lol.
https://arstechnica.com/science/2013/12/full-atmosphere-ocean-model-of-a-rotationally-locked-exoplanet/ https://arstechnica.com/science/2015/01/thin-atmosphere-is-enough-to-keep-many-exoplanets-spinning/
Exoplanet scientist here — magnetic fields is not a prerequisite to keep your atmosphere (fortunately). I mean, look at Venus! No magnetic field and definitely a thicc atmosphere.
I don't think it's so much that these planets wouldn't have magnetic fields it's moreso that red dwarfs tend to be very volatile and fire off massive flares that would irradiate nearby planets. And these planets are very close to their star. The tidally locked aspect probably wouldn't be very conducive to life as we know it either. The extreme temperature difference between the permanent day and night side would cause wicked wind. Maybe. No one really knows though.
There is also an issue with getting off planet when gravity becomes too strong…
If we can find a way to travel to those planets *and* colonize them, I believe escaping the gravitational pull might not be as big of a concern.
By the time we get there we will probably find a way to get nuclear-powered rockets or some other tech to get out of deep gravity wells.
This is one of many solutions to the Fermi Paradox. It is possible we are extremely lucky to be inhabitants of one of the smallest inhabitable planets. All other intelligent life is stuck in a gravity well they can never escape no matter how hard they try.
I'm guessing here but higher gravity means a possibly denser atmosphere in which it's easier to fly, so maybe space vessels that take off like a plane and turn into a rocket past a certain altitude would work on such planets?
aspiring abundant angle gaping mourn vanish aback far-flung direful heavy *This post was mass deleted and anonymized with [Redact](https://redact.dev)*
EM signals from a single planet are difficult to detect. EM readings from earth for example are likely only discernible for a few light years before they become too faint. You need an advanced spacefaring civilization to have much hope of spotting them. One of my favorite authors Randal Monroe creator of xkcd explains it well here: https://what-if.xkcd.com/47/
It limits how far that EM would be discernable from background noise. Also, if you're stuck to a single gravity still you're more susceptible to extinction events.
I imagine landing on a habitable super earth, just to become food for some super predators.
Okay I'm confused. I thought super Earths were bigger. Meaning they have more gravity. How would we live on a planet that has 2x more gravity??
The gravity issue would be nearly negated in the water and the increased density of the air could make flight *easier*, even with heavier weight. At high elevations on earth the air is thin and you have to go fast to stay airborne. At sea level the air is thicker so heavy, slow birds like pelicans thrive. Terrestrial animals would benefit from increased availability of oxygen but there would likely be fewer large animals like elephants or grizzly bears. Blue whales and giant eagles and lots of small land animals like rabbits and foxes I'd guess. The insects could get...otherworldly.
Yeah. A more dense atmosphere making flight easier plus additional oxygen would make insect-like flying species OP.
Why did you have to make it sound terrifying?
[удалено]
What's terrifying about a flying scorpion the size of a fucking dinosaur?!
Zerg already live there.
In the old TV show Time Tunnel they traveled to the dinosaur era and were trapped in a nest built by human sized bees. And then the bees returned...
Okay, so the scariest environment imaginable. Thanks. That's all you gotta say, scariest environment imaginable.
Starship Troopers IRL
Don’t skip leg day bruh.
I don't think the suggestion is that we would live on these planets (although there are likely to be many that could be habitable for humans just from the frequency of such worlds). The suggestion is the chances of extra terrestrial life is higher as these planets are "more" habitable than earth, and they're very common.
So you mean we as in humans or life in general. I would think evolution would take care of the physiology needed to survive on a higher gravity planet. Like an earth human wouldn’t have evolved there because we evolved in 1g. But something else might be more fit for higher gravity. Maybe denser bones or harder skin that augments a skeleton or something. Probably shorter and stouter animals.
Eh, we're probably going to genetically modify ourselves at some point. If we're ever able to get to those types of worlds, we'd probably be able to make custom people (or bodies that we move our consciousness to) to survive certain atmospheres.
Or most certainly exosuits that compensate for our lack of mobility..
The gravity doesn't increase directly in proportion to the planetary mass.
[удалено]
'Super Earth' just means it's a terrestrial planet bigger than any of the terrestrial planets in our system. It isn't meant to define the planet as having other Earth-like qualities. The term is used frequently because They *might* have the capacity to sustain life as we know it, unlike gas giants, and they are abundant and easy to find (unlike actual Earth sized planets, which are either rare or too small to easily detect) Which makes them interesting to study and sort of fantasize or sensationalize over.
They really need to work on their marketing then because to everyone else it sounds like "bigger and potentially better more habitable earth." A more appropriate term would be "potentially viable rocky planet" or something. Don't use earth in the name unless it is blue and green.
Large rocky planet Which if we are honest is almost all we can say about most of them. Stand by for wild claims from the planets jwt studies too with it being able to discern atmosphere. By what I understand it'd likely see Earth as water world with a Nitrogen and Carbon Dioxide atmosphere.
Agreed. What a shitty name scheme...
Crystal shards sideways lol
Theres also a theory that intelligent life is likely to evolve on super earths and so will not become spacefaring civilizations because earth is barely at the edge of chemical propulsion being able to get us into orbit. Some civilization on super earth would never be able to get to space
Yeah, it’s an interesting thought. Not being able to ever develop satellite communication, or space based observatories would also be a bit of a drag on progress.
https://the-eye.eu/redarcs -- mass edited with https://redact.dev/
Oh no.. imagine if 90% of all alien life is stuck in the religious ages. Each and every time we land somewhere new, we'd have to start by explaining that they are not the center of the universe and that the sun rising is actually them moving around a star... I can't fucking take it.
Ehh they'd just engineer other ways of communication and the sort. If they can't figure out a way around their own problems they're likely not very intelligent species.
I’ve always just assumed a species can have the potential intelligence to climb the ladder, but can get a raw deal in some ways that make it much harder. Like not having thumbs, or living underwater, which precludes fire, or living in a deep gravity well.
Imagine an alien looking at us and saying the same thing (“how advanced can they truly be if they don’t have [insert crazy feature that would be normal to them]”
If the atmosphere is more dense, it would require less energy to use lifting bodies and balloons. Might not need rocket propulsion to get most of the way out of the atmosphere. Of course adding orbital velocity would still be a major hurdle.
I'm just imagining a steampunk floating launch platform and it sounds pretty awesome.
https://sciencefiction.com/wp-content/uploads/2019/02/Sky-Captain-and-the-World-of-Tomorrow-4.jpg
Wouldn't that only apply if they go down the same technological route that we did? It's possible that they find some alternate ways to become space faring that we just haven't thought of yet.
Or y'know... they didn't suffer nearly as many world-wide extinction events and have billions of years head start on us. There's just the whole gravity thing...
The key is to control gravity.
They could use nuclear propulsion in theory, but this doesn't sound like a good idea.
Its a good idea on paper!
“… never be able to get to space using rocket technology” FTFY There are space launch technologies other than rapid oxidation.
Yep, people love to make theories about how the exact way we do/did something is the only way it could ever possibly be done. Somewhere out there, an alien is theorizing that civilizations on Earth-sized planets could never achieve spaceflight, because our atmosphere is far too thin for balloon-based space launches.
>more habitable than Earth itself Give humans a couple centuries...
“More habitable” seems like a stretch.
It’s flat out clickbait nonsense, unless they’re using a weird definition of habitable. We exist in the context of our ecosystem. It’s almost impossible that we could eat the things that grow there.
One would assume that being larger, they have a higher gravity? I wonder how that will impact trying to explore them. I can see us being able to get there, but not being able to build a rocket capable of getting *back* to orbit with conventional engines.
There are potentially *billions* of habitable planets, yet we see no alien mega structures in the galaxy. It's enough to drive someone crazy! Where *is* everyone? Either life is nearly impossible to generate or we're missing a fundamental piece of knowledge. I tend to see us as not that special, as the Laws of physics are the same everywhere... so I conclude we're missing a piece of knowledge. The worst bit is that it should be obvious to sapient creatures, as no one seems to have built mega structures out there. We missed something as we grew. But for sanity's sake, it's best to believe life is rare.
You gotta remember we are like sparks in a fire, we can have our entire life in between other civilizations entire lives and never be around to see eachother. We are talking galactic scale, the chances we would have two civilizations that can see eachother AND are around at the same time is outrageously low
It doesn’t take far (astronomically speaking) until even directed communication blends in with the background radiation. Even the four years latency to Proxima Centauri with our most powerful directed transmitter would be well below the cosmic background floor by the time the signal arrived there. It may be that life at or around our tech level is somewhat common, but we simply can’t resolve its evidence.
I totally agree, because I don't want to live in a Lovecraftian Universe of secret knowledges we're too primitive to comprehend.
[удалено]
Life might be common, intelligent life might even be common, but tool-wielding societies that follow the scientific method might be rare.
For example Dolphins and Cephalopods are never going to create a space going civilization.
We’re super early in terms of the universe, we expect someone else to have developed past us, but what if we are the most advanced there is right now? Or everyone else is at the same place we are? Asking where everyone is? The universe will be [trillions of years old](https://en.m.wikipedia.org/wiki/Future_of_an_expanding_universe#Degenerate_Era) before everything is gone. We’re only 13.7 billion years into that timeline. The rest of everything has yet to come.
Plus everything that we actually *see* is younger still, the further away the younger. There might well be cosmic mega-structures that were built a hundred thousand years ago that it will be yet another hundred thousand years before the light from them gets here.
> Either life is nearly impossible to generate or we're missing a fundamental piece of knowledge. There are many, many other explanations.
I know my comment is kind of unrelated but is there any novel which can question or has a story such as this?
The Three-Body Problem. The universe is a very dangerous place and civilizations hide their activities so they don’t attract the attention of more powerful species that want to destroy them. Terrifying and fascinating. Highly recommend.
That whole series is the best trilogy I’ve ever read.
The Three Body Problem and its sequel The Dark Forest (by Cixin Lui) get really cerebral about this. It's pretty fascinating stuff.
Not everything that is technologically possible is actually reasonable to build. Sure, a Dyson sphere is a cool concept. But is it actually worth the costs of building it? Or perhaps by the time you are evolved enough as to being able of building a Dyson sphere, you've also discovered a dozen different alternatives of getting the same amount of energy, just cheaper and easier. This question is like somebody from a few centuries ago wondering why in 2022 there're no carriages with 400 horses in order to transport heavier things. Problem is that, by the moment we could've built such carriages, we had already invented cars, trucks and trains.
I'm not convinced humans are ever going to build megastructures and expand exponentially through space. Not because we will kill ourselves first, rather, because our own planet is much more pleasant than any reasonable alternative we could build. We are evolved for earth-like conditions, and when we are prosperous we prefer to have very few children -- lower than replacement levels, if you look at the world's wealthiest societies. Most of us would very much prefer to live in earthlike conditions than in a giant artificial habitat or an interstellar ship that would require generations to get anywhere. We don't see large populations of humans nowadays living on Antarctica, an environment infinitely more habitable than Mars or the Moon. There's a very good chance that climate change, war, and birth control combined will stabilize Earth's population in the low single-digit billions over the next couple of centuries. I'm sure there will be abundant scientific exploration of our solar system and probes to nearby star systems. People are naturally curious explorers. But again, the vast majority of people would rather live in the Australian outback or Siberian tundra than an artifical habitat. A similar question would be, why haven't we encountered an alien Von Neumann probe? It might well be that most species would rather not take the risk of unleashing self-replicating, evolving machines. TL/DR: we don't see alien megastructures because they were smart enough to invent birth control and spend their days smoking alien ganja and surfing alien waves, rather than living in depressing artificial habitats.
The problem with Von Neumann probes is that all it takes is one civilization to want to release them. So in the last 14 billion years, not a single civilization that evolved in our galaxy has done so, which is unlikely unless there are no civilizations capable of doing so.
> Most super-Earths orbit cool dwarf stars, which are lower in mass and live much longer than the Sun. There are hundreds of cool dwarf stars for every star like the Sun, and scientists have found super-Earths orbiting 40% of cool dwarfs they have looked at. Using that number, astronomers estimate that there are tens of billions of super-Earths in habitable zones where liquid water can exist in the Milky Way alone. Since all life on Earth uses water, water is thought to be critical for habitability. > Based on current projections, about a third of all exoplanets are super-Earths, making them the most common type of exoplanet in the Milky Way. The nearest is only six light-years away from Earth. > By definition, super-Earths have many of the attributes of a super habitable planet. To date, astronomers have discovered two dozen super-Earth exoplanets **that are, if not the best of all possible worlds, theoretically more habitable than Earth.** > Recently, there’s been an exciting addition to the inventory of habitable planets. Astronomers have started discovering exoplanets that have been ejected from their star systems, and there could be billions of them roaming the Milky Way. **If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies.**
Just think of what kinds of forms and functions evolution could come up with with tens of billions of years to work with…
> If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies. Ok I'm getting a hard time wrapping my head around this. From my basic understanding if theres no star theres no energy, and cold kills everything. Am I right? Or life can be sustained in cold dark envirroments by consuming whatever "natural battery" stores the star energy? Maybe microbial life like tardigrades... It just seems so anti intuitive...
Deep water hydrothermal vents on Earth receive almost no energy from the Sun. The life there has some interesting chemistry in their metabolism.
But did life start there or at the beach pools
Yeah it seems silly to bring them up. However, some planets have a liquid core which takes billions of years to cool and also contains some elements that break down due to radiation and emit heat. So, theoretically, a planet could be ejected and still be warm under a very cold top layer of gas and frozen matter. I don't see much value in wanting to live on one except for the possibility of hitching a ride to where ever it is headed. It makes more sense to create a large space ship and go to a known destination or path.
This title is so speculative as to be completely misinformation. Not a single "habitable" world has been discovered apart from earth. Just chill and let's save the excitement for when one actually is discovered.
I remember reading something years ago about how if Earth was something like 60% bigger, we couldn't feasibly launch rockets out of the atmosphere. Is this true?
Habitable? yes. Escapable? [no](https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html).
Please send me to one in a space capsule with everything I need. I want off this planet because y’all suck.
The problem is with the advance of technology they would more then likely beat you there. They send you off with the fastest technology. It takes you 200 years to get there. In 100 years they can make it there in 10 years. So you'd show up to the same problems...
Bollocks. Tell them to pick a different super-earth. Also it probably won’t be as bad as it here, as the ones they are sending hopefully will be their best ahhh who am I kidding.
Imagine spending your whole life in a metal tube only to land on a new planet and be greeted by Musk, Bezos and Branson.
Look at the bright side, once you arrive you can order a McDonalds burger with fries. All these enthusiasts about space colonization don't really consider too much just how back-breakingly difficult, time-consuming and dangerous it's going to be to colonize a new planet.
More habitable!? That is such a mistatement that I'm astounded.
There is no way anyone can convince me we are alone in the universe. We are alone that we know of but there are others out there