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Super-Earths are ideal targets in the search for life
- nawgz 4y agoInteresting idea. To me, exoplanet surveys are one of the most exciting forms of science. I can think of no other thing that would bring us closer to understanding whether or not life does exist in our universe beyond us. I've long held that it does, but it feels to me that belief is practically religious, completely unfounded. Combined with the fact that I think no other event will impact our world for the better more than knowing this universe has other life... I have my fingers crossed for the giant ground-based teles they listed at the end. Godspeed
- throwaway743 4y agoI'm gonna get downvoted to hell, but watch the doc, The Phenomenon. It's pretty damn convincing. As you said, yeah it's a leap of faith without (at least publicly available) empirical evidence, but who cares. It's fun thinking about the possibilities of others out there, interacting, and sharing with them. Even better if they share their tech so we can travel distances off and away from this crumbling rock. In any case, I believe we've already been contacted, at least since nuke testing, and that the US andnother govs have recovered craft that are handled by contractors. Watch the doc. It's not woo woo crap. I mean Harry Reid is in it and he implies a lot to say thr least. Here's a link, just use uBlock to get rid of the ads https://www1.kk01.net/movie/the-phenomenon-66483 https://www1.kk01.net/movie/the-phenomenon-66483
- sammalloy 4y agoI’m familiar with the so-called evidence you’re discussing. The thing is, there’s no reputable, authoritative source that will go on record right now saying we are positively being visited by aliens. Nobody seems to know exactly what the phenomenon is, if it really does exist. More to the point, the notion of aliens themselves could very well be a culture-bound idea, just like angels and demons and fairies and spirits. We just don’t know. It could very well turn out to be propaganda and disinformation that hides something else entirely.
- denton-scratch 4y ago> one of the most exciting forms of science. Not to me, I'm afraid. Suppose we detect CO2, methane and ammonia in the atmosphere of some exoplanet tens of lightyears away. Hell, suppose we detect definite evidence of life. What difference is that going to make to anything? We couldn't launch a probe that could get there in a lifetime, going at half the speed of light. We certainly couldn't get the probe back again. You'd need a generation ship to get people there. I'm quite sure there's life out there. I'm also fairly sure that very little of the life out there is organised for (or interested in) interstellar travel; and for most destinations, that life would have evolved by the time of arrival, and the space-traveller would be something that can only live in space. A civilisation that can build a rocket has existed on Earth for only a few decades, and might only last a few decades longer. We could certainly send a probe to Proxima Centauri. Our great-grandchildren could record the results, if they'd spent two lifetimes keeping the probe in contact and under control (fairly boring astronomy career: maintain contact with a spaceship that was launched before you were born, and won't arrive before your grandchildren have died).
- floxy 4y agoI'd still like to look at them: https://www.youtube.com/watch?v=NQFqDKRAROI https://www.youtube.com/watch?v=NQFqDKRAROI https://arxiv.org/abs/1802.08421 https://arxiv.org/abs/1802.08421
- hedora 4y agoIt's interesting that planets could roam between solar systems for 10's of billions of years before becoming uninhabitable, and that such planets are likely common.
- lumenwrites 4y agoThis would be such an amazing premise for a scifi movie. One such planet drifts through the solar system, and we have like 3-5 years to make contact with whatever lives there before it drifts away.
- bolasanibk 4y agoShorter time scale but - Rendezvous with Rama by Arthur C Clarke
- Something1234 4y agoThere was extraterrestrial life in that one, or am I thinking of hammer of god?
- jabbany 4y agoThere kind of is already: https://en.wikipedia.org/wiki/The_Wandering_Earth https://en.wikipedia.org/wiki/The_Wandering_Earth The premise is that humans turned the Earth into a planet-scale space vessel to escape the sun's expansion and rehome into a different solar system. Basically involved de-orbiting the Earth and coming up with a way to fling it out of the solar system whatnot. The sci-fi parts are quite interesting, though I'd recommend the book instead of the movie (which is really a mediocre Chinese take on the Hollywood blockbuster...)
- teh_klev 4y ago> which is really a mediocre Chinese take on the Hollywood blockbuster. I quite enjoyed the film. It was interesting to see a different cultural take on how to solve "future problems" in a different cultural SciFi. Would I watch it again? Probably not, was it any worse than the stream of MCU junk? Not really.
- awb 4y ago> By definition, super-Earths have many of the attributes of a super habitable planet. Is that true? https://en.wikipedia.org/wiki/Super-Earth https://en.wikipedia.org/wiki/Super-Earth > A super-Earth is an extrasolar planet with a mass higher than Earth's, but substantially below those of the Solar System's ice giants, Uranus and Neptune, which are 14.5 and 17 times Earth's, respectively.[1] The term "super-Earth" refers only to the mass of the planet, and so does not imply anything about the surface conditions or habitability.
- uup 4y agoThat's mentioned in the article: > A super-Earth is any rocky planet that is bigger than Earth and smaller than Neptune. If you read further in the article, it explains why super-Earths are a good target to look at for extraterrestrial life.
- awb 4y agoBut the “by definition” part seems incorrect. Nothing in the definition of “Super Earth” indicates superior habitability.
- uup 4y agoThe author goes on to explain why super earths are a good place to look for habitable planets. It’s the entire point of the article. Planets meeting this definition also tend to have other characteristics as well.
- shagmin 4y agoIt may not be worded well but it does state why. Planets of this size are more likely to be geologically active, a sufficient size to retain an atmosphere thick enough for life, a strong enough magnetic field, etc.,. Just due to their size, they are better suited to support life then (at least as we know the conditions necessary). I mean between the other options - planets so small they're basically rocks in space and giant gas planets with a bunch of other issues - it seems this classification of planets indeed offer superior habitability.
- ramraj07 4y agoI suppose one cannot expect anything better from a site called singularity hub, but this post is disingenuous (or written by an actual hack) for multiple reasons. Aren’t the majority of planets we are discovering all orbiting red dwarfs, which can exhibit massive swings in luminosity and be very violent? Even the example quoted by the author which such a short radius seems one of them. Also what do you do in a tidally locked planet? Half if not 90 % of it is likely to be unsustainable. Also a rogue planet without a star might be able to sustain simple life but without human sources of nuclear power the only source of energy would be geothermal, so not exactly exciting candidates for living. Also who wants to live in a planet in perpetual darkness? Either the “astronomer” author wasn’t a real astronomer at all or this is just clickbait.
- dhruval 4y agoSorry for in advance for the dumb question... Are red dwarf planets over represented due to detection methods? Or is there some sort of astrophysics related reason red dwarfs would be more likely to have super earth class planets in orbit? Basically should we hold out hope that with better detection techniques we will be able to detect more planets that are similar to our own.
- ramraj07 4y agoMy understanding is it’s a combination of both - red dwarfs are the most numerous and super earths are the most easiest to detect with them (smaller star, larger the effect of the planet on its characteristics and luminosity). I am also convinced we will find planets better suited for us than earth eventually. But I doubt any of them would be in any meaningful close distance. Even if you can imagine a 100 year or 500 year ship (like in Expanse) that can get to a planet 10 LYs away, imagine if it’s 100 or more. We might be SOL.
- bagels 4y agoBetter suited in what way? Humans are pretty well adapted to Earth specifically.
- NotACop182 4y agoImagine being intelligent life on a super earth 2.5-3x larger than earth but trapped on the planet due to gravitational forces.
- eigenhombre 4y agoBeing already semi-intelligent, and trapped here, also due to gravitational forces, I think I can sort of imagine it.
- NotACop182 4y agoYea but our civilization can still make it to orbit. It would be very very hard for them to leave the planet.
- metamet 4y agoAh, so this is why they haven't visited earth yet.
- rizzom5000 4y agoIt's also why they wouldn't have orbiting satellites which would be incredibly useful for both exploration and communication systems.
- NotACop182 4y agoa rocket on a super-Earth would need to have a mass of about 440,000 tons (400,000 metric tons), due to fuel requirements, the study said. That's on the order of the mass of the Great Pyramid of Giza in Egypt. Just imagine the effort to get one satellite up. Now this would open the door for them to find new ways to make it to orbit.
- denton-scratch 4y agoLoads of small nukes. https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...
- every 4y agoWe didn't evolve there so we most likely couldn't survive there. And these planets are so distant we will almost certainly never visit there. Essentially nothing more than entertaining pipe dreams...
- jrvarela56 4y agoOh we will, just not in these meat suits.
- tgv 4y agoThe chances of mass extinction are a tad higher than those of use uploading to some non-corporeal construct and travelling at lightspeed.
- jrvarela56 4y agoWe can do the upload first and figure out lightspeed travel while in there. Chances of figuring out the upload before we do the extinction are higher imo. This whole AI boom may make it happen sooner than we think. It won't be the upload we all expect ("Am I me in there?") but it'll have human-like thoughts and consume the data we've produced so it'll be us/human in as fluffy a way as we define consciousness right now.
- tgv 4y agoI don't think there will ever be an upload. That "AI boom" is nothing more than the capability to train very large networks, and (that's indeed a first) a recurrent one. But it doesn't resemble our way of being and thinking. But your variation makes it pertinently clear that it's not "us" who's going to visit those planets, but something else entirely. And why would we need a "super habitable" planet if we're just electrons in a few chips, anyway (ignoring the fact that electronics tends to die in 20 to 30 years of use, but hey)?
- dhbradshaw 4y agoThis is exciting, but I think I'm most excited about learning to make self-sufficient and self-replicating colonies in space. If we focus on settling planets, then each planet is its own set of problems. But if we focus on learning to live in space, then although it may be harder initially, it's a single problem to solve. Then we just keep working and improving on that solution. And there's a lot more space out there than there are habitable planets. And there's a lot more matter and energy out there than are available on those planets.
- bee_rider 4y agoI don't really understand the idea of colonizing a planet. If it is going to be totally independent of Earth, you'll have to set up the entire industrial base and population of that planet. If it is going to be economically linked to Earth, then we're going to have to deal with shipping stuff there. And, like, what will they sell to Earth? I guess it would have to be really valuable and specific to that planet, to justify manufacturing it there and then lifting it out of a massive gravity well. Space colonies at least have the hypothetical benefit of zero-g industry, aren't downwell, and can move around. Space colonies in the asteroid belt are the way to go, IMO.
- Ekaros 4y agoAlways thinking of the making all the stuff. And I mean literally all the stuff, everything needed during life. In probably more hostile environment than we live. Probably would get old rather fast...
- TheOtherHobbes 4y agoToo many people believe you can colonise planets with the modern equivalent of a horse and covered wagon. You can't. It's much, much harder than that. Getting to any kind of self-sufficiency anywhere is going to be incredibly difficult. You literally have to invent a complete industrial production chain for materials, machinery, and food and air that operates in a completely different and much more hostile physical environment with a completely different mix of available raw materials, much less solar energy, and no initial biosphere.
- divbzero 4y ago> 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. What would be the energy source to sustain life on an ejected super-Earth? Radioactivity? Tidal forces from orbiting moons?
- mr_toad 4y agoI don’t think we’re exactly sure how much of the Earth’s heat is due to radioactive materials in the core or just left-over heat from its formation, but either way a super Earth should have more of both.
- hinkley 4y agoOne of the early pieces of evidence for the existence of radioactivity had to do with the fact that the Earth’s core is way too hot to be billions of years old. Even if there were coal veins down there just burning slowly forever.
- tambourine_man 4y agoYeah, I wondered about that as well. It must be radioactive and residual heat from the core. I can’t imagine geothermal supporting as vibrant an ecosystem as photons pouring in everyday allow photosynthesis to do.
- njarboe 4y agoThis seemed off the me also. Reading through the paper quoted in this sentence makes it clear that the sentence is just wrong. From [1]: "The team found that planets 10 times the mass of the Earth, with an atmosphere 100 to 1000 times thicker than Earth’s, may be the most favorable for storing life for billions of years. But to do this, they must orbit the star at a distance that the orbit of Mars occupies in the Solar System. At such a potentially safe distance, the original atmospheres can act as greenhouse gases, absorbing infrared radiation, providing the necessary heat and pressure that can support life in oceans of liquid water." So the planet is not ejected from the system, just pushed out so that instead of an orbit of days it is as far away as Mars is to our sun (1.5 AU). Gell-Mann Amnesia comes into play here. [1] https://universemagazine.com/en/life-on-super-earths-can-exist-for-84-billion-years/ https://universemagazine.com/en/life-on-super-earths-can-exi...
- 29athrowaway 4y agoIf they're bigger then they have more mass and therefore a higher gravitational pull, which makes every task more expensive.
- teh_klev 4y agoWe don't have to live there. If there is a sentient industrial space faring equivalent of our species then trade, cultural exchanges etc can be performed off-planet. There are ways around these problems.
- Chris2048 4y agoDepends on the density, and the distance from the surface to the centre.
- Qem 4y agoNatural selection would just favour smaller body sizes. Ants can lift tens of times their own weight. The question is, what's the minimum body mass that would still allow human-like intelligence?
- sidcool 4y agoWouldn't it be physically impossible to escape the gravity of a super Earth using the currently available and known propulsion technology we have here on Earth?
- jccooper 4y agoNot quite, but as mass increases relative to Earth, launch vehicles become increasingly ridiculous. Many "super-Earth"s would need something like a Saturn V to get to their equivalent of the ISS, or maybe even their equivalent of Sputnik, depending on exactly how "super". When you start to get into gas giant mass, chemical launch starts to become really close to impossible instead of just wildly unaffordable.
- hinkley 4y agoWe haven’t even come up with a material strong enough to build a space elevator here on earth. On a heavy planet you need an even higher strength to weight ratio. Your space platform would practically have to be a floating city, since mountains won’t even be as high.
- JadeNB 4y agoThe actual title "Super-Earths Are Bigger and More Habitable Than Earth, and Astronomers Are Discovering More of the Billions They Think Are Out There" is doubtless too long for HN, but the mangler truncated it at the "Di" of "Discovering", which is surely suboptimal.
- dang 4y agoYes, and also somewhat baity. We've replaced the title with a representative phrase from the article body.
- philsnow 4y ago> So the most habitable planet would have roughly twice the mass of Earth and be between 20 to 30 percent larger by volume. So, ~60% denser than Earth? Density is mass/volume, and 2x / 1.25x = 1.6x. The math works out really well if they meant a 20-30% larger radius: 1.25*3 = 1.95, so similar density but larger volume.
- rbanffy 4y agoSuper Earths are easy to find and super common but I am almost betting the most life will be found in gas giant moons. Even though we don’t have any gas giants in our own system that have Earth-sized rocky moons, each one of ours has half a dozen “almost-there” moons. A civilisation developing around a gas giant with multiple habitable and easily accessible moons would be very interesting.
- zeroth32 4y agoMagnetosphere of planet like Jupiter or Saturn is the most radioactive place in solar system... Also energies (delta V) needed to travel between Jupiter moons are greater, than those needed for travel between solar planets.
- rbanffy 4y ago> Magnetosphere of planet like Jupiter or Saturn I thought Saturn was mostly benign. My hope was that a magnetosphere would protect the moons from the early outbursts of the red dwarf. > Also energies (delta V) needed to travel between Jupiter moons That's surprising. Found this nice map [1] and the numbers are really disappointing. ~15 kps from Titan-to-Iapetus sucks (even though it's ~4 kps less than Earth-to-Mars). At least the distances are smaller...
- graycat 4y agoApparently there is high interest in finding life elsewhere in our galaxy, or in other galaxies. Since a lot of such interest is resulting in US federal government funding and I am a US citizen, I have standing, if only as a taxpayer, in this interest. About this interest and paying to pursue it with my tax money, I ask "Why should I?". I confess that getting good evidence of such life would be curious, entertaining, fun, etc. For any in doubt, I will just stipulate that there is a lot of life out there in our galaxy and the rest of the galaxies in the universe. Done. No more wondering or arguing. If you want, I'll also stipulate that they are all little, green, and have 10 legs and 5 eyes. And I will agree that we might find evidence of a Dyson sphere (build a sphere around a sun and collect all or a lot of the energy it radiates). Second, but I will insist that, from all we know about physics now, there is no way for us ever to have anything like practical two way communications with any life that evolved outside of our solar system. Third, with current physics, the search for life is at best just curious, entertaining, fun, etc., and, sorry, on these criteria some good movies are better! I can buy a good movie on a DVD for about $10 -- so if I give $10 for the search for that life, I'm all paid up? Fourth, really, then, the search for such life needs to include a search for some radical new physics. If want to pursue promising research directions in such physics, okay by me, but such research efforts should be low budget unless very promising, and I doubt that there will be any promising directions. So, net, whatever astronomy, astrophysics, etc. are good for, the search for life that evolved outside of our solar system is not very serious -- or, such life IS there but with current physics there are no significant consequences for us. Sorry 'bout that. Or, a big effort on the search for such life looks to me like some researchers want to do a big selling job to get taxpayers to give them an interesting career. Sorry 'bout that. Or, if the search for life is mostly just for a search for some radical new physics, then sell the effort as a search for the physics, not the life. Or I agree already that there is a lot of life out there, but with our current physics there are no consequences for us -- stipulate that they are all green with 5 eyes and get no conflicting data.
- genericone 4y agoThe alternative: make billions selling ads so you can finally sell the company to really focus on your passion of spending billions on developing tech and lobbying for policy towards searching the cosmos for life.
- anentropic 4y agoWhat does "more habitable than earth" even mean? Habitable to whom?
- mrtri 4y ago
- fsiefken 4y agoso we probably are not alone. the next questions for me are: how rare is first "one-way" contact between intelligences? and how rare is asynchronous two-way contact (centuries or milllenia in between messages) and how rare is two way immediate contact in our galaxy?
- jjoe 4y ago> While there are many reasons why a habitable world would not have signs of life, if, over the coming years, astronomers look at these super habitable super-Earths and find nothing, humanity may be forced to conclude that the universe is a lonely place. Interesting... The "no" is definitely cheaper and faster than the "maybe" or "yes." If we get a "no", what's next? Planet-wide depression?
- api 4y agoYes means there is life out there. No means there isn't life in the specific place we looked, but the universe is very big. So no is really pretty meaningless.
- thathndude 4y agoNo has to be understood to be “maybe.” if there’s one negative that will be very very hard to ever approve, this is it.