[HN Gopher] Rogue planets could outnumber the stars
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Rogue planets could outnumber the stars
Author : dnetesn
Score : 74 points
Date : 2020-08-22 11:11 UTC (11 hours ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| keithwhor wrote:
| I think it's kinda cool to consider that rogue planets / brown
| dwarfs [0] could be candidates for extending human life beyond
| the solar system post-Sol. Assuming we have enough fissile
| material (or master cold fusion) to perpetuate the civilization's
| energy requirements, we could explore the stars in darkness for
| eons.
|
| I'm not sure how likely they are as candidates for life to emerge
| spontaneously, it seems like there's a very high energy input
| requirement over billions of years (Sol -> Earth) to get anything
| close to human civilization... but it's cool to think that,
| perhaps, some future humans could settle a planet eternally
| cloaked in darkness. Adapt to the reality of that planet over
| generations... and be unable to acclimate to life near stars at
| all.
|
| Also, post-Andromeda collision, is this a _necessary_ future for
| posthuman life? [1] Billions of cold worlds will be flung into
| the far reaches of the Universe.
|
| [0] https://en.wikipedia.org/wiki/Brown_dwarf
|
| [1]
| https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_co...
| sgt wrote:
| Agree that would be very exciting. However, I think one has to
| consider maneuverability of the planet, effectively making into
| it a very large spaceship. It won't exactly turn on a dime, but
| it's crucial to alter its heading in some way, at the very
| least to avoid getting caught up in the gravitational orbit of
| another star. I wonder about the energy requirements for
| something like that, while still having enough to make it a
| safe place to live with a magnetosphere etc.
| Causality1 wrote:
| If you can generate enough energy to move a planet you'd have
| a far easier time just making a starship big enough for your
| whole species. The entire biosphere of earth occupies the
| volume equivalent of the skin on an apple. Just accelerating
| earth to solar escape velocity would take 3E24 joules.
| ncmncm wrote:
| It is generally quite difficult to get "caught" in orbit. You
| start out with enough energy to leave again. Big planets
| catch asteroids as moons only after millions of passes,
| generally involving interaction with another moon to steal
| some energy.
| grawprog wrote:
| >I think it's kinda cool to consider that rogue planets / brown
| dwarfs [0] could be candidates for extending human life beyond
| the solar system post-Sol. Assuming we have enough fissile
| material (or master cold fusion) to perpetuate the
| civilization's energy requirements, we could explore the stars
| in darkness for eons.
|
| Every time I read a comment like this I wonder if people have
| actually taken the time to consider what living off the Earth
| would actually be like.
|
| The quality of life for anyone living off the Earth would be
| abysmal. Think of the most barren, hostile, nearly
| uninhabitable places on Earth, they're still magnitudes higher
| in habitability than anywhere we're likely to find outside
| Earth.
|
| Then if somehow we actually manage to find a place with a
| climate similar to Earth, that may even have some life or
| organic material, there's the issue of compatibility.
|
| Look at the issues humans have just travelling from one side of
| the world to the other. Pathogens, the environment, even the
| food can cause problems, let alone a place with entirely alien
| life.
|
| Take something as simple as the prion that causes mad cow
| disease, it's a protein.
|
| What kinds of bacteria, virii, amoebas, fungi, parasites etc.
| Will we encounter? Would we even know we're infected until it'a
| too late?
|
| Maybe some kind of strange prion or virus that systemically and
| harmfully alters humans in a way that's undetectable until the
| whole population is infected?
|
| I mean this happens still here, with life on our own world.
|
| But, before all that is the endless darkness, entire
| generations living like nomads in the cold, black emptiness of
| space. Entire generations seeing nothing, living their lives
| only so their children's children's children can maybe someday
| see something.
|
| Overall though, the idea that we can just escape the Earth
| someday so it'll be fine just leads to shortsighted neglectful
| actions that destroy the planet.
|
| That colonial, we can just expand and keep growing indefinitely
| and just move to a new place, mindset stopped being reasonable
| the moment we spread across the world. Moving to a new planet
| is not the same as just hopping in a ship and sailing across
| the ocean. It's not a reasonable backup plan, it's not a
| reasonable solution.
|
| We have one home, Earth, we are all made from this place,
| someday we go back to it. No other place we ever may find will
| be our home the way the Earth is. The idea we should just use
| and abandon the Earth is just so incredibly backwards to the
| way we should be thinking.
| PaulHoule wrote:
| With my math I see it is just possible with materials we have
| to build an O'Neil style colony large enough that it doesn't
| need a roof, a spacecraft could graze the atmosphere, re-
| enter and land, it would be a large and comfortable place,
| but it's hard to afford large amounts of relief (e.g. make
| some alps to climb) Not sure if people then would think
| Nitrogen is too dear to do such a thing.
|
| Show me a journal bearing that is good for 10 km/sec velocity
| difference on the outside and you could 'pack' the habitable
| section with a non-rotating structure that holds it in and
| then you can imagine a 'small ringworld' similar in diameter
| to the Earth but with much better ratio of living area to
| mass.
|
| Either way that is a large environment that people could make
| the way they like.
|
| If one wants to live on a 'planet', I would picture the base
| on Luna will be one of those SpaceX starships turned on it's
| side somewhere near iron deposits and soon it will be joined
| by steel cylinders made by indigenous material. Oxygen and
| Iron will be abundent, but I worry about Carbon and Nitrogen.
| Either way the cylinders will be buried under a few meters of
| soil -- it will be like spending all your time inside
| widebody airliners but having to be careful not to jump too
| high or you'll hit your head.
| moralestapia wrote:
| >The quality of life for anyone living off the Earth would be
| abysmal.
|
| I agree with the general sentiment of your post, however,
| this may not be necessarily true. If you have a shelter that
| provides adequate conditions for life, that's it. Sure, no
| more walks in the park, but still doable. Plenty of people
| have not left their homes at all in the past few months and
| they seem to be ok-ish.
| tomrod wrote:
| Indeed.
|
| We humans adapt our environments to our needs. There is no
| reason this would not occur off Terra Firma.
| grawprog wrote:
| No...that sounds pretty abysmal to me. But I guess if you
| don't appreciate the outside world on your own planet it
| doesn't really matter.
|
| >If you have a shelter that provides adequate conditions
| for life, that's it.
|
| I mean so do prisons, generally, or well they're supposed
| to, most people wouldn't choose to live in one though.
| moralestapia wrote:
| >I guess if you don't appreciate the outside world
|
| I never said that. Sorry, I didn't know you were throwing
| a tantrum. I thought we were having an honest discussion.
|
| I can tell you, for sure, that there are people on this
| earth which are living under an overall _worse_ standard
| of living than the one you would probably find in early
| mars colonies; and they outnumber people like us, with
| food, clean water, internet access, etc... That obviously
| sucks, but to say that life on Mars is going to be
| necessarily worse than life on Earth is an argument that
| is quite easy to disprove.
| darkerside wrote:
| What slum are you talking about that is worse than living
| in what amounts to a slightly larger ISS? Rio? Dharavi?
|
| Not the parent, but it made a good point, so I'm curious
| about yours.
| harimau777 wrote:
| I'm not sure it's fair to characterize it as a slightly
| larger ISS. The root poster was suggesting a colony the
| size of a planet.
| moralestapia wrote:
| Check this [0]:
|
| "Around 9 million people die every year of hunger and
| hunger-related diseases"
|
| "A child dies from hunger every 10 seconds"
|
| and also, by the end of the article:
|
| "2.5+ billion people in need of water"
|
| I don't care if its a "slum" or not, it could be
| happening in Switzerland and it wouldn't make a
| difference for me as I'm not discussing the "aesthetic"
| side of the argument. If people on a Mars colony have
| enough food and water (which they almost certainly will),
| they will be doing better than the ones referred to at in
| the article.
|
| 0: https://www.theworldcounts.com/challenges/people-and-
| poverty...
| wcarss wrote:
| This (and the parent) both require a kind of paucity of
| vision or imagined capability -- endless subterranean
| hospital hallways and infinities of military bunkeresque
| quarters would indeed be abysmal, but there is no
| particular reason we could not instead build sweeping
| open spaces full of light and life and visions we've
| never dreamed, if we were so capable as to profitably
| settle a rogue world.
|
| Sure, it could (and likely would!) be hard to make it not
| suck to live in a place like that. But if we're going to
| indulge in wild future space colonization fantasies, we
| certainly don't need to stop and get mired in the
| economic feasibilities of the potential lifestyles there
| to the point that they become depressing.
|
| Imagine "Halo", not "HAL"!
| radu_floricica wrote:
| Yeap. Indoor space in a seismically dead world is very
| cheap. Energy is presumably also cheap. Paint the ceiling
| blue and you ciuld have real sized California.
|
| For a contemporary example, people pay a premium to go to
| the mall. Just scale it up - not even a lot, 10x or 100x,
| and you basically have paradise. Far from abysmal.
| darkerside wrote:
| And then the population expands to fill that space. Then
| what? It's a lot harder to expand your hermetically
| sealed environment than it is to cut down a few trees.
| whatshisface wrote:
| Uhh... Digging more Mars holes is a lot better than
| cutting down trees.
| darkerside wrote:
| Surely you don't think expanding a sealed base within a
| hostile environment is that easy?
| perl4ever wrote:
| >entire generations living like nomads in the cold, black
| emptiness of space
|
| The most logical objection to interstellar travel, which I
| don't see you making, is that once you have your generation
| ship, another star is only an unnecessary risk and an
| infinitesimal chance of a congenial planet. If you can live
| without a solar system, why do you want to camp next to an
| unshielded nuclear reactor and poke around the surrounding
| debris?
|
| On the other hand, if something the size of the K-T asteroid
| or larger was headed for Earth and there was a substantial
| amount of time to prepare (say 1000 years) then it doesn't
| matter if people want to abandon it. And I think in that
| time, it's reasonably possible.
| senko wrote:
| > Every time I read a comment like this I wonder if people
| have actually taken the time to consider what living off the
| Earth would actually be like.
|
| Parent is explicitly refering to human life post-Sun:
|
| >> extending human life beyond the solar system post-Sol.
|
| It took us only a few million years to get off the trees and
| invent Bitcoin.
|
| If, by some chance, civilization once called human will exist
| at that time (2000x longer than current span of human
| species), all the problems you described should be trivial
| for them.
|
| And if by then, by some chance, due to countless generations
| of people sharing your view on the matter, they don't set off
| for the stars - they deserve to burn.
| booleandilemma wrote:
| Maybe any expansion does require a few generations to toughen
| up and live a spartan frontier lifestyle. It wasn't easy for
| the first colonists to come to the new world, it won't be
| easy for the first colonists in space. But in the long run
| humanity will be better for it. We have to take the first
| step, otherwise we never would have left Africa.
| wruza wrote:
| Fair points, but only assuming that "we humans" will still
| remain mostly biological by that time. Which is barely
| suitable for anything complex, including modern tasks and
| parts of life.
| michaelmrose wrote:
| The kind of people apt to be excited about humanity expanding
| beyond this globe in the future is literally the exact same
| population that is enthused by environmental causes.
|
| The problem we face isn't thinking that we can throw away the
| earth and get another one it's the fact that we are short
| lived and short sighted.
|
| You are taking pot shots at exactly the wrong people.
| grawprog wrote:
| >You are taking pot shots at exactly the wrong people.
|
| These fantasies tend to come from technocrats and
| transhuminists.
|
| Transhumanists very much would like a world where
| everything is sterile and manmade, where the natural world
| doesn't get in the way of human technological progress and
| advancement.
|
| The belief that humans are very much above nature and the
| world around them and that it needs to be controlled and
| manipulated to suit our whims, whether that's exploiting it
| for resources, or trying to manipulate it to some ideal
| state.
|
| The idea that we can leave this world and turn space or
| some other world into some 'humanified' place that's
| suitable to us stems from this same idea of human
| superiority over our own world and the universe and that
| somehow, we can make it better, more suitable for us.
| whatshisface wrote:
| > _that somehow, we can make it better, more suitable for
| us._
|
| Assuming you live in a house, car, tent, lean-to or any
| other kind of shelter, you're calling yourself a
| "transhumanist" with this extremely broad definition.
| perl4ever wrote:
| It seems to me that "transhumanist" implies changing
| _oneself_ to fit the environment, more than the other way
| around.
|
| I wouldn't call myself such, but I think if humans _do_
| colonize anywhere off of Earth, it will require modifying
| what a "human" is to where it is possible to live with
| much less technology in today's sense.
| kzrdude wrote:
| I think the Andromeda collision is likely to not even disturb
| our solar system.
|
| Just like asteroid fields in movies are way too dense, it's
| easy to overestimate what the collision means. It's two
| _galaxies_ that collide, but their parts don't. Their
| individual star systems may all pass around each other quite
| well, for the most part.
| oh_sigh wrote:
| It's not collisions that would be the problem, but the
| interacting gravity throwing previously stable orbits out of
| whack.
| perl4ever wrote:
| There are ~1.5 trillion stars in Andromeda + the Milky Way
| combined, so I read.
|
| Saying that they are mostly empty space seems like a way of
| rhetorically obscuring the common sense idea that close
| encounters and collisions would become more likely.
|
| Also the statistical distribution of velocities would be more
| heterogenous, wouldn't it? Bimodal? That ought to have some
| noticeable effect on dynamics. You also have, I assume, a
| second central black hole doing something, maybe disrupting
| an otherwise stable system.
|
| It's just weird to say, although it seems to be somewhat
| popular, that objects in space don't collide, when on the one
| hand, anyone can look at something like the Moon, and
| asteroids that look like rubble piles, and we also "listen"
| to much larger things colliding via LIGO, and I assume people
| in astronomy related threads know about the central black
| holes in galaxies that grew to millions of suns.
| hinkley wrote:
| On the other hand, the Oort Cloud is likely to experience a
| shift in elliptical orbits, eventually causing a lot of
| damage in-system.
| antman wrote:
| If I recall it is not a matter of physical collision but
| disruption due to the gravitational fields.
| nojokes wrote:
| Maybe, but there is also this:
|
| As of 2006, simulations indicated that the Sun might be
| brought near the centre of the combined galaxy, potentially
| coming near one of the black holes before being ejected
| entirely out of the galaxy.[11] Alternatively, the Sun might
| approach one of the black holes a bit closer and be torn
| apart by its gravity. Parts of the former Sun would be pulled
| into the black hole. [0]
|
| [0] https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way
| _co...
| kiba wrote:
| There's nothing preventing our descendent from steering the
| sun by the time our galaxy collides with the Andromeda
| galaxy.
| dmd wrote:
| My hand and the wall are both made of matter that consists
| almost entirely of empty space, and yet when I punch the
| wall, it hurts, because of the electric fields involved.
| edgyquant wrote:
| That's a couple billion years from now, no? By that time
| human will either be a kingdom of species or extinct. Kind of
| weird to talk about it effecting mankind in anyway.
| keithwhor wrote:
| I'd consider all future progeny, "humankind." It matters
| not what my grandchildren look like; only that they have
| the opportunity to partake in the beauty that is the
| conscious experience of this Universe.
| the8472 wrote:
| > (or master cold fusion)
|
| Why cold fusion specifically?
| keithwhor wrote:
| Forgive me if I misrepresented fusion energy as a technology;
| my understanding was that the implication of "cold fusion"
| was simply "sustainable fusion." i.e. the all-in energy cost
| is less than the energy output at scale.
|
| I think that's most people's understanding of "fusion",
| generally, Matter -> Energy, but "cold" is the qualifier of,
| "we've created fusion reactions before. We just haven't
| sustained them in a net-positive fashion."
| ISL wrote:
| From a numeric standpoint, this seems like a reasonable
| conclusion. For the system we know well, there are eight times as
| many planets as there are stars. A lot of systems in which
| exoplanets have been observed are known to have more than one
| planet.
|
| The only way this is unlikely to be the case is if planets remain
| strongly-bound to stars.
| apotatopot wrote:
| Some of the stuff being announced about space seems to me like
| scientists restating stuff we should've known 50 years ago. Like,
| our star has more than 2 planets around it. If that's the case
| with lots of stars, then it's obvious there would be of a higher
| number of planets going "rogue".
| awb wrote:
| > An upcoming NASA mission could find that there are more rogue
| planets -- planets that float in space without orbiting a sun
| -- than there are stars in the Milky Way, a new study
| theorizes.
|
| I don't think we've detected a single rogue planet, so this
| theory would seem novel to me.
| ericbarrett wrote:
| There's at least one candidate:
| https://en.wikipedia.org/wiki/CFBDSIR_2149%E2%88%920403
|
| (edit) Linked from the same article, a confirmed rogue
| planet: https://en.wikipedia.org/wiki/PSO_J318.5%E2%88%9222
| TheGallopedHigh wrote:
| It's difficult because they generally do not radiate EM waves
| or specifically visible light.
| kabdib wrote:
| We first detected exoplanets in 1992 (that was for a planet
| orbitig a neutron star, for one orbiting a "vanilla" star it
| was 1995). So until 25-30 years ago, we had NO data on the
| frequency of exoplanets. Exoplanet hunting really only hit its
| stride in the 2010s.
|
| Things have become a lot clearer in the last couple of decades.
| I guess it's easy to take our current knowledge for granted.
| nend wrote:
| Well, science doesn't really operate by assuming what the truth
| is. If it did it wouldn't be science.
|
| And if it's so obvious that we should've known this 50 years
| ago, you could've gone down in history as the scientist who
| discovered this truth. But instead you're complaining on the
| internet about other people trying to prove it.
| apotatopot wrote:
| Except I wasn't alive 50 years ago. Shows what you know, Mr.
| Jerk.
| nkrisc wrote:
| Well now's your chance to discover what should be so
| obvious right now that people on the internet will dismiss
| it as obvious 50 years from now.
|
| So what you got?
| tachyonbeam wrote:
| Actually, informed guesses make a lot of sense when we have
| limited data. Science doesn't operate by assuming that we
| know nothing outside of what we have evidence for. That
| wouldn't be logical at all. That being said, it is of course
| interesting and valuable to confirm our hypotheses.
| mromanuk wrote:
| If humanity is still around in a few hundred million years, they
| could use the earth as the vessel to escape the sun before it
| devour us.
|
| https://www.space.com/22471-red-giant-stars.html
| sxp wrote:
| > Johnson said these planets are not likely to support life.
| "They would probably be extremely cold, because they have no
| star," he said. (Other research missions involving Ohio State
| astronomers will search for exoplanets that could host life.)
|
| This depends on the nature of the planet. Some planets with
| internal heat sources like Earth or Jupiter wouldn't be frozen.
| They wouldn't have liquid water on their surface, but they might
| have warm and habitable conditions somewhere in the planet for
| certain definitions of "habitable".
|
| _Passages in the Void_ is a set of stories from Kuro5hin where I
| first read about rogue planets sustaining life:
| http://localroger.com/ They were written by the same author as
| _Metamorphosis of the Prime Intellect_ and are interesting sci-
| fi.
| m3kw9 wrote:
| More likely these planets harbour super advanced life as the
| don't need to depend on an external energy source, exposed to
| planetary event risk, and can control their own fate. Maybe they
| can even change trajectory given their advancement
| qayxc wrote:
| I'm afraid that doesn't follow at all.
|
| Life requires an energy source and the only energy sources a
| rouge planet has, are leftover heat from its formation process
| and nuclear decay.
|
| The energy released by geological processes is too localised
| and too little to allow for widespread higher lifeforms.
|
| Even the comparatively active Earth doesn't generate enough
| heat on its own to keep its oceans liquid (e.g. 100mW/m2 at the
| oceanic crust and <70mW/m2 at the continental crust) or a
| gaseous atmosphere of any kind.
|
| In order to generate enough heat to keep a liquid ocean and an
| atmosphere (both are required for higher lifeforms as of our
| current understanding), the planemo needs to be quite large or
| have at least one big moon in a close orbit.
|
| The first case is very likely to generate an ice giant like
| Neptune or Uranus, both highly unlikely to harbour any kind of
| life.
|
| The second case is probably very rare - the event that led to
| the ejection of the planet would've also affected any moons. In
| addition, close orbits either rapidly decay (see Deimos on
| Mars) with the moon crashing onto the surface within just a few
| million years; or they recede over time due to the exchange of
| angular momentum between the two bodies (see our Moon).
|
| In conclusion, while planemos may indeed harbour microbial life
| in the form of extremophiles living in their crust, any
| multicellular life is very unlikely to have survived the
| ejection event and subsequent loss of a host star.
|
| Formation of life on a free floating planet is very improbable
| and "super advanced" life requires stable conditions over
| billions of years and sufficient energy, which simply isn't
| available for the reasons mentioned above.
|
| Feel free to correct me if I got something wrong, though.
| [deleted]
| database_lost wrote:
| Maybe someone with more knowledge on the subject could answer,
| but could a much larger than expected number of such bodies
| partially explain Dark Matter?
| hinkley wrote:
| In addition to the behaviors mentioned by others, even if this
| doubles the amount of "normal matter" in the universe, that
| still leaves us with an explanation for less than 10% of the
| stuff we can see.
| rudolfwinestock wrote:
| No. Being ordinary matter, these objects occlude light. If
| there were enough of them to make up for dark matter, or even a
| large fraction of it, then we wouldn't be able to see much past
| our galaxy.
| jetru wrote:
| YES! None of these news articles seem to address this important
| question.
|
| Edit: I meant "yes, someone with more knowledge please answer
| this question". Not "yes, it could be dark matter"
| dnautics wrote:
| MACHOs where eliminated as an unlikely consideration a long
| time ago:
|
| https://en.wikipedia.org/wiki/Massive_compact_halo_object
|
| (that doesn't mean it's categorically wrong, just decided to
| be so unlikely to be correct that it's not worth our time)
| BurningFrog wrote:
| No, and I blame naming it "dark matter" for this idea always
| popping up.
| ivalm wrote:
| Probably not since dark matter tends to not radiate even when
| accreating next to galactic nucleus/pretty extreme conditions.
| This is in part why dark matter is less clustered than normal
| baryonic matter (nothing to shave off angular momentum). If it
| was planets they would heat up in the accretion disk, radiate
| light, decay orbit, and fall into the black hole.
| aidenn0 wrote:
| I thought there were some convincing arguments that dark matter
| couldn't be fermions, but that's a vague memory.
|
| [Edit] I think it was actually baryons which are composites of
| an odd number of fermions if my memory of college physics is
| right
| jleahy wrote:
| Yes it's baryons. There is some missing baryonic matter
| (probably dust), but the bulk of it is something else (black
| holes, WIMPs, etc).
| sbierwagen wrote:
| For the confused: Nancy Grace Roman Space Telescope was formerly
| the Wide Field Infrared Survey Telescope. They renamed it in May.
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