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Two potentially life-friendly planets found orbiting a nearby star
- skribbj 7y agoHow common are "life-friendly" planets (Let's say: on a ratio of Life-Friendly Planet:Non Life-Friendly Planet)? And is there any way to check if life-friendly planets contain life without actually going there?
- jerf 7y agoA good question. No sarcasm, it depends on your definition of "life friendly". Right now, we can't see much more than an orbit and a mass for these things. (There's a spectrum on a few of them, but AIUI for most exoplanets we're still just getting them from star wobbles, which gives us only orbit and mass.) Combined with the stats for the stars themselves, we can say whether or not they could conceivably be in the "liquid water" zone. But we can't say that they are definitely suitable for life. If Venus and Mars were found orbiting other stars, the press release would declare they could be "life-friendly"; if you squint a bit, both are at least on the edge of where you could get liquid water under the right circumstances. Being much closer to the real Venus and Mars, we know they are both not actually great candidates, because we can see the details that prevent them from being useful clearly. So I'd say "life-friendly" is a continuum, and kinda relative to the amount of knowledge we have about the planet, which for most exoplanets right now, is very low, making the "life-friendly" bar correspondingly low. Detecting life in general is impossible; we are fairly sure Earth has had life on it in the past that did not meaningfully change the spectrum of Earth. However, there are some signatures that would be very, very, very suggestive. From what I've gathered, Earth's atmosphere containing free oxygen isn't quite proof of life from a single snapshot, as there are conceivably processes that could produce it momentarily, but having oxygen in our atmosphere consistently for millenia and eons is difficult to explain with anything other than life.
- maxxxxx 7y agoThere are plans for doing spectrography on the atmospheres of these planets. This would allow us to get a pretty good picture of the chemical composition. Biological life as we know it should leave a different footprint than a lifeless planet but in the end we can only extrapolate what we already know about life.
- civilian 7y agoYep! And more specifically, if we found a planet that had an atmosphere with O2 in it, that would be highly indicative of life. Although it's not the only option, O2 is pretty reactive, and you need a constant O2-producing force to maintain it. An O2-producing force would be something like plants or some life that is creating hydrocarbons from CO2 and H2O.
- Robotbeat 7y agoI don't know that exact ratio, but the number of stars that you can see that probably have planets in their "habitable zone" is pretty high... One in 5. https://www.popsci.com/article/science/one-five-sun-stars-have-earth-planets/ https://www.popsci.com/article/science/one-five-sun-stars-ha... In our solar system, 2-3 of the 8-9 planets are in the "habitable zone". So let's just say it's maybe one in 20 or so.
- aiyodev 7y agoOver the last two decades we’ve gone from not knowing if there were any planets in other solar systems to knowing that almost all of them have planets. We now know the second factor in the Drake equation is nearly 100%. We don’t yet know the third factor yet, the percentage of planets capable of supporting life. But we do know about 22% of planets are small enough to possibly be rocky and are within the “habitable zone” of a star. So a possible answer to your first question is that it’s likely 0-22% of stars have at least one planet capable of supporting life like that on Earth. This doesn’t say anything about moons or asteroids or the probability of life developing on a body that could support it.
- wefarrell 7y agoI'm curious to know if Mars would be considered life-friendly from 12 light years away.
- pault 7y agoAs other commenters have said, we don't have the tools to see that far yet, so it's only through a miracle of math, physics, and engineering that we can deduce the size, distance from the star, and atmospheric composition of exoplanets from variations in the brightness and color of a distant star over time. The James Webb telescope should help, but because of the nature of the technique our observations are constrained to solar systems that are perfectly aligned with ours, such that the planets pass directly in front of the star relative to the observer. It's possible that we can survey enough of those stars to get a rough idea of the ratio of life friendly planets, but we'll likely never know for sure. Maybe conditions for supporting life are correlated with alignment to the galactic plane!
- trollied 7y agoI wish Earth was always life-friendly. It feels so anti-everything at times.
- bsmitty5000 7y agoMaybe you meant to say Earth is anti-human. Earth is incredibly life friendly. There's been five previous mass extinction events and each time life has rebounded amazingly.
- TwoNineA 7y agoI was under the impression that planets to be life-friendly have to be close to their red dwarf star to a point they'll be tidally locked (one side always light other night), meaning their atmosphere would freeze on the dark side and planet would end up without an atmostphere.
- CWuestefeld 7y agoThis was my first thought, too, when I saw the article. But our thoughts about the effects of tidal lock on the emergence of life is little more than philosophy, having only one datapoint to extrapolate from, at that one not being tidal locked.
- bmurphy1976 7y agoI think there are other loopholes. Imagine a Jupiter sized planet that had an Earth like moon. The Jupiter size planet would probably be tidally locked with the star, but the moon could be tidally locked with the planet, not the star. Given that, it would have quite a varied and complicated day/night cycle.
- quakeguy 7y agoInterresting setup you mention there, the earth-like planets d/n cycle would indeed be very irregular i imagine, depending which orbital speed it would have.
- wongarsu 7y agoAtmospheres are useful, but are they a requirement for calling a planet life-friendly? Life on earth first developed in liquid oceans, not in the atmosphere.
- consp 7y agoWouldn't an ocean vaporise somewhat automatically to create an atmosphere of there wasn't one already?
- deleted 7y ago[deleted]
- hirundo 7y ago> Teegarden’s star is a stellar runt that’s barely 9 percent of the sun’s mass. It’s known as an ultra-cool M dwarf Is it too late to change the name to Tyrion Lannister?
- wibble10 7y agoTyrion Lannistar
- petercooper 7y ago"just 12 light-years away" I love the "just". I know it's nearby on galactic scales but it's practically about 450,000 Earth years away with current technology :-)
- TeMPOraL 7y agoAnd "just" 24 years over radio if there's anyone there to talk with ;).
- petercooper 7y agoI doubt I'm alone in this, but I do find it simultaneously amusing and depressing how mind bogglingly big the universe (or even the galaxy) is. It's clear that discovering entirely new levels of physics will be necessary to stand a chance of going anywhere.
- api 7y agoOr extreme life extension, or fully digital AI. Life span is a big part of the problem. Personally I doubt that meat will go to the stars. Planets, sure, and maybe bases or settlements. The stars take too long.
- TeMPOraL 7y agoYou're not alone. I grew up reading and watching a lot of sci-fi. Today I recognize that most of it was garbage in terms of physics, but I'm still saddened that the universe isn't that easy - we can't just hop on a space cruise ship and do a tour of a nearby nebula...
- guru88 7y agoDo these planets have their own moons?
- sampo 7y agoMoon-size objects are probably not detectable with current technology.
- vkaku 7y agoStop teasing me, Universe - and show me the aliens already!
- zspade 7y agoJust as long as the universe doesn't show us to the aliens, I'm on board.
- krisroadruck 7y agoCheck out the Dyson Dilemma for a well-reasoned theory as to why it is a high probability that there is no space-faring intelligent life anywhere in our galaxy or even perhaps our super-cluster. https://www.youtube.com/watch?v=QfuK8la0y6s https://www.youtube.com/watch?v=QfuK8la0y6s
- sulam 7y agoThere are holes wide enough to fit a solar system through that argument. Reductio ad absurdum. Here, I'll construct an argument in a similar form. People don't like mosquitos, for various reasons including that they transfer deadly diseases. Therefore the presence of mosquitos says there's a high probability that the planet isn't actually inhabited by us, because we would have killed them by now. After all, we have the technology. Maybe, by the time we get around to wanting to construct a Dyson Sphere, we will have found a better alternative. Maybe they aren't a good idea for any number of reasons (if you need one, read the Cixin Liu "Dark Forest" series). Any argument of the form "X is inevitable but hasn't occurred, therefore Y" first needs very strong proof of the inevitability of X.
- fastball 7y agoTo be honest, I've never really understood how a Dyson sphere would be superior to many nuclear fusion reactors that you can move around / turn off and on / build more of / etc
- michaelmrose 7y ago
- _Kristijan_ 7y agoFeels like we're playing the first round in "Master of Orion" when you start scanning the stars around you ;)
- jzawodn 7y agoI still love that game.
- WhompingWindows 7y agoI remember around 2003, making huge battleships in that game and squaring up against the AI's armada. The AI made about 500 tiny ships with weapons incapable of breaching my shields, and with their own shields incapable of surviving my dreadnought blasts. I would kill 5 with my big ships, take no damage from 495 shots, rinse and repeat. The battles took hours! I had to skip tactical battles, couldn't stand that much time, just had the AI simulate it.
- newnewsrenew 7y agolife friendly planets and new battery tech are just fantasy.
- pault 7y agoWhat are the consequences of a star that mostly radiates infrared light for habitability? Would it restrict what kind of life could evolve there?
- mabbo 7y agoBeing that close also offers us a better ability to examine it. The nearer the star, the more arc-seconds (or tiny fractions thereof) the star will appear in telescopes. 12ly is ridiculously close! It also tells us something interesting. If we presume there's nothing special about our little corner of the universe, then the distance to the nearest potentially habitable planets gives us an estimate of how many habitable planets are out there. Only 12ly away and that one has maybe two habitable planets? That tells me the universe is teaming with potential homes for life.
- joshuahedlund 7y agoYes 12 ly is amazingly close! > If we presume there's nothing special about our little corner of the universe, then the distance to the nearest potentially habitable planets gives us an estimate of how many habitable planets are out there I would put a slight caveat to this - I would argue we do know there's something "special" about our little corner of the galaxy, at least - we are in the continuously habitable zone - for example, there are billions of stars at higher densities closer to the core whose planets are likely uninhabitable due to toxic levels of radiation, GRBs, etc. So I actually might expect other planets near us to be more habitable on average than at least some other places in our galaxy. But I also think it's too soon to know how potentially habitable these planets are, until we have a chance to check a bunch of other things on the checklist, like the long-term stability of the sun's output and the planet's orbits, the frequency of destructive solar flares, the frequency of asteroid bombardments (if there are no Jupiters to absorb them), etc. Regardless the close distance should make it much easier to answer these sorts of questions than it would be far planets much farther away, and I'm excited to see what we can learn in the coming years.
- soulofmischief 7y agoWouldn't each system's star do a decent job of pushing back extra-solar radiation? Up to a point, obviously, but it would seem that planetary background radiation levels aren't a direct function of solar density.
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- dboreham 7y agoTelephone Sanitizers and Hairdressers back your bags!
- westoque 7y agoWaiting for the moment where we actually find a habitable planet with intelligent life. Next thing you know, we'll be developing ways in order to communicate with them, not just observing them.
- dheera 7y ago"Habitable" in also relative to our Earthly form of life. There may be other architectures that prefer different temperatures and pressures, perhaps.
- SEJeff 7y agoOr aren't primarily carbon based whatsoever.
- joshuahedlund 7y agoI highly recommend the book The Equations of Life: How Physics Shapes Evolution[0] . While it's be foolhardy to rule out other dramatically different forms of life, there are only so many candidates in the periodic table and only so many of those in common concentrations throughout the universe. The universal laws of physics that continually converge on the same solutions on Earth, and the fact that life has apparently failed to succeed even on nearby planets (perhaps at all, and certainly not advanced life) with different conditions suggests that it's at least unlikely to find life thriving at far different temperatures (atoms just don't hold together or move enough) or bases (I wouldn't completely rule out silicon, either, but the author makes a good case that carbon is far more likely) [0] https://www.amazon.com/Equations-Life-Physics-Shapes-Evoluti.. https://www.amazon.com/Equations-Life-Physics-Shapes-Evoluti....
- dheera 7y agoWhy does life have to be chemical as we know it? Why can't a massive galactic-scale lifeform exist upon gravitational waves, radioactive particles, or even dark matter or things we don't know?
- simmanian 7y agoLife isn't something that's easy to define because literally everything exhibits patterns of life to some degree (in fact, you could definitely argue that the concept of life is an arbitrary, fictional distinction made to make our lives easier). For example, we find that cities, states, and empires look "alive" at a macroscopic level, with cars and roads forming the circulatory system to deliver much needed nutrients to far corners of the respective territories; we often give anthropomorphic characteristics to planets (Mother Earth) and stars. When we search for life, we're probably looking for something very similar to us, something we can interact with and befriend.
- XorNot 7y agoThe note that it's an old star makes me worry though. If they're older then us, and habitable, were they inhabited? Our current era is a few hundred years of real, directed technological development. A few thousands years either side of that and who knows what we'd be looking at, but you imagine that - hopefully - the general progression of technology is forward. So if they were inhabited, what happened to them? Are they exactly at our level of development? Earlier? Hopefully. Because later poses some real big questions - does technology top out about where we are now - no FTL travel, no really big radio transmitters or stellar engineering? No probes to nearby star systems? Did they even make it past the nuclear age, or avoid wrecking their climate? One thing's for sure - if there's really 2 habitable planets, with liquid water, then we've got a hell of a target to point James Webb at when it launches - an infrared spectrum star should mean any plant life is well optimized to towards the redder end of the spectrum - we should see some type of chlorophyll.
- inetknght 7y ago> Are they exactly at our level of development? If so, then at just 12ly away, we could converse with them within (many of) our lifetimes.
- entropea 7y agoWhat are the chances that would've already happened given how long we've been sending life made RF off the planet? A 24 year exchange isn't awful.
- CondensedBrain 7y ago12 light years is a long way for a signal to go without attenuating into noise.
- deleted 7y ago[deleted]
- matt-attack 7y ago
- cptaj 7y agoAnd to think that there is likely an Easy Mode system out there. A habitable planet on the low end of the mass spectrum needed for a stable atmosphere with other habitable planets in-system. And all that close to another star with habitable planets, possibly in the sub-lightyear range. Basically everything ripe for a spacefaring civilization to grow without too much trouble and with plenty of motivation. The Earth is hard to leave and everything else in our system is dead rocks with hellish environments as far as we know with the nearest alternative at least dozens of lightyears away
- zilian 7y agoMaybe the Great Filter is real and screwing up a system is as easy as screwing up a planet ;)
- LeifCarrotson 7y ago...why the winky face?
- zilian 7y agoWhy not ? Maybe sentient / intelligent life is thriving everywhere but 99.9% of time, climate change or nuclear annihilation happens. Even in "easy mode" with several planets. I find it ironic and somehow poetic.
- LeifCarrotson 7y agoI believe (like many people) sentient/intelligent life to be intrinsically valuable, and the suffering or extinguishing of that life to be bad. Our own species suffers and harms itself far too much already. I like to think that we're doing relatively well, solving problems and navigating bad Nash equilibria and local optimizations with social systems and technology to make the world a better place. In as little as the last century, we've made huge strides in solving problems of hunger, illness, education, freedom of expression, and more. Even with the huge efforts needed to escape our heavy planet's gravity well with chemical rockets, and the limited habitability of other planets in our system, we're exploring the possiblity of colonizing other planets. To imagine that this is a hopeless fight, even at the best of odds - that sentient/intelligent life is not only unable to succeed but is actively continuously exterminating itself across the universe - is a ghastly, horrific, tragic nightmare.
- EGreg 7y agoPerhaps habitable planets will be necessary for human migration and colonization, rather than finding aliens.
- cjbprime 7y agoThe trilogy _Three Body Problem_ is a good read, and has something to say about this. :)
- psychometry 7y agoI had high hopes, but TBP is a terrible novel. It certainly has some fascinating ideas, but just as many ludicrous ones that are equally central to the plot. Not to mention Liu is absolutely terrible at anything relating to characters: dialogue, character development, etc.
- rainygold 7y agoReading that someone else had this opinion of TBP is so valididating. The book receives much hype but the characters are weak and forgettable.
- coupdejarnac 7y agoNot that I want to pile on, but I didn't make it past 100 pages. It's badly written, and I don't want to waste my time when I could be reading something else.
- r00fus 7y agoI agree - I read the trilogy and enjoyed it somewhat but I wouldn't recommend it to others (unlike e.g. Hyperion Cantos or Fire Upon the Deep, etc). The amount of suspension of disbelief for some questionable premises is very high. e.g. the real-time comms developed by one of the races breaks down one of the key axioms.
- ohaideredevs 7y agoI read TBP and A Deepness in the Sky at the same time. Despite the "big ideas", TBP isn't even in the same league. Can't bring myself to read the second TBP book, just don't care. Did buy a Fire Upon a Deep recently, looking forward to it.
- iamgopal 7y agoHow do we check about life that far?
- clarkmoody 7y ago> The team calculates that one of the planets, called Teegarden’s star b, completed an orbit in a mere 4.9 Earth-days; the other world, Teegarden’s star c, has an orbit of just 11.4 days. I wonder how our understanding of orbital mechanics would have evolved differently had our planet orbited the Sun this fast? If the planets have long days, then they could potentially see in one night what it takes us a full year to see!
- sambeau 7y ago"Seen here in an illustration" This half-hearted attempt to say that the impressive-looking image of The Nearby Star was in fact an artist's impression of what a Red Dwarf might look like, made me laugh. Is it seen here? Or is it an illustration? I suspect someone changed the copy just before publishing
- hughes 7y agoIf you see a picture of the surface of a star that's not our sun, it's certainly an illustration. No such image exists of any other star.
- umeshunni 7y agoWouldn't planets orbiting this close to the star be tidally locked to it? If they are tidally locked to the star, they are also likely to have extreme temperature variations between the two sides. This could rule out life.
- vikasnair 7y agoIf that’s true, as it is true for planets in the TRAPPIST system, then at least there is a potential for life to develop around the thin longitudinal slices located more centrally, where climate may be more temperate. Also see this comment below, something I wasn’t aware of: https://news.ycombinator.com/reply?id=20212953&goto=item%3Fid%3D20212374%2320212953 https://news.ycombinator.com/reply?id=20212953&goto=item%3Fi... I’m curious- at the end of the article, one of the scientists remarks that the stars might be “zipping around” their host star faster than measurements predict, which could rule out potential for life. Is this referring to your suspicion re: proximity => tidal locking => extreme temperatures? Or is there some way that speed of orbit can affect potential for life?
- CWuestefeld 7y agoI saw a study recently, unfortunately I can't locate it now. It discussed the possibility of there having been past civilizations on Earth, hundreds of millions or even billions of years ago. The conclusion was that this can't be entirely ruled out. It noted how few actual fossil remains we have for what we know of dinosaurs, and that there's a lot of space left in those gaps for all the evidence to have been destroyed.
- caymanjim 7y agoIt's incredibly improbable. While much of the planet's surface is recycled constantly, there are also huge swaths of land that are billions of years old and haven't changed enough to hide evidence of complex society. Dinosaur fossils are rare, but not that rare. Tiny ones are abundant. If all life on earth ceased today, you could come back here in a billion years and find plenty of evidence everywhere. Maybe it's not 100% impossible, but it's so improbable that it belongs alongside other fringe theories.
- TheOtherHobbes 7y agoI like to entertain a mad fringe theory that the K-Pg asteroid was a war weapon. You might think no species would be insane enough to consider bombing its own planet to the point of extinction-level oblivion, but - that doesn't appear to be true.
- yellowapple 7y ago> there are also huge swaths of land that are billions of years old and haven't changed enough to hide evidence of complex society Do you have any examples? The article in the sibling comment to yours directly states that the oldest large-scale swath of land (in the Negev Desert) only dates to 1.8 million years.
- caymanjim 7y agoThat's the oldest surface land, but the oldest crust is 4.4 billion years in Australia, and there are other places with less-old-but-still-billions crust. Natural erosion in those areas exposes extensive history, and we can dig too. [1]: https://news.nationalgeographic.com/news/2014/02/140224-oldest-crust-australia-zircon-science/ https://news.nationalgeographic.com/news/2014/02/140224-olde...
- JaggerFoo 7y agoYou got me. I'm from one of those planets. A group of us decided to move to earth for the warmer weather. It's also why most of us live in California and Florida. Tan Mom is our leader.
- Tepix 7y agoThere was a paper recently that argued that the habitable zone is smaller than anticipated because either the concentration of carbon dioxide will be too high (and thus toxic at least to life on Earth) or - for small stars like this - there will be (toxic) carbon monoxide in the atmosphere. https://phys.org/news/2019-03-complex-life-require-narrow-habitable.html https://phys.org/news/2019-03-complex-life-require-narrow-ha... (good article with link to the paper)
- nine_k 7y agoLife on Earth lived in CO2-dominated atmosphere for 1.5B years. If anything, CO2-rich world which is not overrun by SO2 and chlorine and phosphoric anhydride and scorching heat, like Venus, is as "potentially life-supporting" as it gets, save for a world with actual oxygen-producing life like ours.
- aflag 7y agoLife, uh, finds a way: http://www.bbc.com/earth/story/20170125-there-is-one-animal-that-seems-to-survive-without-oxygen http://www.bbc.com/earth/story/20170125-there-is-one-animal-...
- totaldude87 7y agoIf there is a Life friendly planet, which is much older than where we live, shouldn't there be life forms? Shouldn't those be searching for other life supporting planets, vigorously than us since they would be much mature and advanced? why no one found us? WHAT IS THE PROBABILITY OF US FINDING AN ALIEN VS AN ADVANCED RACE FINDING US AS ALIEN?
- gattr 7y agoAs for interesting consequences of a vastly different planetary age: in one SF novel (could be Peter F. Hamilton's, I can't remember right now) humans colonized an Earth-like planet only some 2 billion years old or so. Its uranium ores had so high U235 content (as opposed to Earth's 0.72%, which requires costly enrichment), that you could simply smelt it and put straight in a reactor (cheap nuclear-powered locomotives anyone?).
- wppick 7y agoBy the time our technology reaches the point that we could feasibly travel to and inhabit another distant planet, and with all the challenges with that (space travel, terraforming, radiation protection), couldn't we feasibly create or move a planet or gigantic space station built from materials of another planet into whatever orbit we want?
- radium3d 7y agoYes, possibly, but my curiosity about the natural life on those other planets outweighs that thought.
- reneberlin 7y agoHow long will it take until the next planet is overpopulated and resources are consumed? I mean: birth control? Socialism? Rules to obey? If it is a competitive race it will end up pretty much the same. The question is then only: how long will it take? Over to the next one ...
- m3kw9 7y agoWhy aren’t we discovered? Probably because an advanced civilization but barely reach for the first time would be wise not to fly in risk getting detected and captured. So they wait till they have overpowering cloaking ability before re attempting a sighting. Maybe by that time, we are no longer interesting because of their own advances
- m3kw9 7y agoAlso there is probably a super small probability where both civilizations are in similar advances that they can brave a encounter without worrying. If one is way more advanced, either one may not be interested, or the less advanced one chickens out/ gets destroyed because they want to hide their location.
- m3kw9 7y agoFor those that wants to live on another planet, you will unlikely like how things look under another suns sunlight. It is hard to have a planet that will have day light like our sun and be habitable. Think of a yellow-reddish, or a light that is cold blue when you walk out. Human eyes evolved with earths lighting conditions.
- rossdavidh 7y agoYou assume that any of us ever go outside to see the light on Earth, anyway.
- m3kw9 7y agoWhat I’m interested in is if somehow there is a planet almost exactly like earth, if so would they have evolved humans similar to us.
- hakanito 7y agoI too like this thought experiment! Checkout the movie Kpax with Kevin Spacey if you haven’t already, it touches on the subject — ”Why is a soap bubble round? It’s the most efficient form”
- tamaharbor 7y agoTo think 'life' can only thrive in an earth-like environment is extremely naive.
- inevitable2 7y agoSo much crap... "defacto" science is now dead! Yes please, keep this hyper junk speculations running wild and wide, so these "space" programs can suck as much money as they can, and funnel the money into 3 letter word pus organizations in order to transform the world we live in in a prison. The American people are so gullible.
- monomyth 7y agoAssuming we have technology to reach a new planet 12 ly away, is going to a red dwarf star a good investment strategy?
- cududa 7y agoIf you have the money and technology to go, you’ll just hop to the next solar system
- deleted 7y ago[deleted]
- siruncledrew 7y ago"nearby"
- known 7y agoI don't think there is redundancy in Universe
- kristianp 7y agoIs it possible to determine the atmospheric composition of these planets? How much water for example?
- kingkawn 7y agoOnly 70 trillion miles away...
- thepangolino 7y agoCalling than A and B