22 ms·

Planet Found in Habitable Zone Around Nearest Star

1187 points by Thorondor 10y ago

Manupok 10y ago
This is cool and all, but my question would be to what end? We can't know if there is water on it, life, or anything else about it really. We can't gauge it's atmosphere, it's 500 light years away so it's way too far to look at it. I guess it's cool to know that there are other planets the size of earth in a habitable zone, but with all the stars in all the galaxies, isn't it quite obvious that there would be some of these? Ok, so now we know there IS one at least, but now what?
api 10y ago
How big of a space telescope would we need to see this planet in any actual detail? One of my sci-fi fantasies is to take a photo of an extrasolar planet and see someone else's city lights. :) Of course if we could see that we could also probably detect their radio emissions, but seeing someone else's lights would somehow be cooler.
- kyriakos 10y ago
  I'm no expert but I'd say you need an orbiting telescope to do that.
- themartorana 10y ago
  At ~500 light years away, even if we did see lights, who would we be communicating with _now_? And would it be disappointing if we saw a technologically-similar civilization that hadn't contacted us yet, being 500 years ahead of us? Sometimes it's romantic to look up at stars that probably died a long time ago. Sometimes I hate that we can't see what's happening now.
  - karmelapple 10y ago
    Where does the 500 light years number come from? Alpha Centauri is only 4.4 light years away from Earth.
    - ogrisel 10y ago
      This discovery is about Proxima Centauri which is slightly closer: 4.25 ly.
  - bengarvey 10y ago
    It's only 4.25 light years away https://en.wikipedia.org/wiki/Proxima_Centauri https://en.wikipedia.org/wiki/Proxima_Centauri
  - verandaguy 10y ago
    Why are people in this thread constantly citing 500 light-years? Proxima Centauri's 4 ly away, which, granted, isn't a walk in the park, but it's remarkably near to us.
  - civilian 10y ago
    Why would a civilization be exactly 500 years ahead of us? While evolution is a powerful trend, I think there's so much randomness about... when their planet cooled off enough (and had enough alkaline vents) to support abiogenesis, when bacteria form eukaryotes, when eukaryotes become multi-cellular, when life moves out of the oceans, when plant-like organisms start producing fruit leading to animals that take advantage of the high-energy food source and are able to develop smart brains--- all of these events could happen +/- a million years from eachother. And that's assuming that their evolution of life followed a similar path! So worrying about a race having 500 years on us is just... a worry based on so many wrong assumptions.
- evilduck 10y ago
  That question pops up on /r/askscience fairly often. Here's one that does the math for the previously closest known Earthlike exoplanet (36ly) and Alpha Centauri (4.5ly). https://www.reddit.com/r/askscience/comments/137klp/will_there_be_space_telescopes_capable_of_taking/ https://www.reddit.com/r/askscience/comments/137klp/will_the...?
  - Gravityloss 10y ago
    For starters, it doesn't seem impossible to build it, on earth or in space. You don't need a continuous mirror of that size. I wonder if any of the LIGO technology can be applied to optical telescopes? https://en.wikipedia.org/wiki/Aperture_synthesis https://en.wikipedia.org/wiki/Aperture_synthesis
- throwanem 10y ago
  > How big of a space telescope would we need to see this planet in any actual detail? Impossibly big. I'm sorry.
  - TeMPOraL 10y ago
    From the link 'evilduck posted, it seems that's big indeed, but possibly big. 240km is a big thing, but within the realm of possibility; also I'm personally hoping someone will invent some magic mathematical trick around phased arrays or whatever, and cut that size by an order of magnitude or two :).
    - throwanem 10y ago
      240km is also what's required to resolve a feature no smaller than 100km across. I'm no mathematician and I am not equipped at the moment to pretend to be one, but to resolve a feature an order of magnitude smaller, I suspect you'd need a much larger instrument.
      - ianai 10y ago
        If I did the math correctly, it turns out to be ~2400km for 10km across (changing 100 to 10 in the eq). This could very easily be wrong as I only glanced through the comment. Think of it as Kirkian mathematics.
    - ianai 10y ago
      I would file 240km under very do-able. It's nothing like, say, a solar system sized particle accelerator.
      - throwanem 10y ago
        That simple? Well jeez, I don't know what I was even worried about. :D
- darkerside 10y ago
  Way cooler, because it would imply they share our visible light spectrum!
  - wcoenen 10y ago
    It's not a coincidence that we can see in the 390 to 700 nm part of the spectrum. These are the wavelengths that pass through water most easily[1]. Any alien lifeforms which started their evolution in (illuminated) water could be expected to be sensitive to the same slice of the spectrum. [1] https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_water#/media/File:Absorption_spectrum_of_liquid_water.png https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_...
- Thorondor 10y ago
  The planet is about 0.05 AU from Proxima Centauri, meaning we need an angular resolution of about 1.9e-7 radians to even distinguish it from its host star. Is that realistic? In theory, an orbiting space telescope has a diffraction-limited resolution of approximately 1.22λ/D (λ = wavelength, D = aperture size). Modern image processing techniques can improve on this somewhat, but it makes a good order-of-magnitude estimate. Anyway, this formula tells us a 4-meter telescope has a maximum angular resolution of about 1.8e-7 radians at a typical visible light wavelength of 600 nm. That would be just good enough... except that we don't actually have a 4 meter orbiting space telescope. Resolving even large features on the planet would require a much larger telescope, probably kilometers or more. For ground based telescopes, the situation is even worse because of atmospheric effects. Despite being 10 meters in aperture, the Keck telescopes in Hawaii are limited to an angular resolution of about 2e-7 radians because of the atmosphere. However, there is reason to hope that the even larger European Extremely Large Telescope will have enough resolution (about 5e-8 radians? hard to tell from their official publications) to image Proxima b directly. https://www.eso.org/sci/meetings/2011/VLTI2011/presentations/Kissler-Patig.pdf https://www.eso.org/sci/meetings/2011/VLTI2011/presentations... Again, this is still not enough to resolve surface features. So, long story short the answer is unfortunately no at present. Maybe space-based manufacturing will let us build a big enough telescope someday?
  - verandaguy 10y ago
    To put things in perspective, what was the angular resolution of Hubble's Ultra Deep Field measurements/photos? (keeping in mind that angular resolution isn't the only challenge here)
    - Thorondor 10y ago
      Hubble's angular resolution is about 0.05 arcsec = 2.4e-7 radians. And you're absolutely right that angular resolution isn't the only challenge here - some way of filtering out the extremely bright (relatively) light from the host star is needed as well, for starters.
  - throwaway_yy2Di 10y ago
- semaphoreP 10y ago
  The most promising technique at this point is to use optical interferometry to resolve the surface of the planet. In this case, you will need two telescopes (likely in space) separated by a baseline distance, "d". The two telescopes will require extremely precise synchronization in both spatial position and timing so that the light they collect will interfere at precisely the right phase, but if this can be achieved, the angular resolution of such a telescope in radians is wavelength/d. An earth sized planet has a diameter of ~13,000 km. To "resolve the planet", we would need to be able to distinguish one half of the planet from the other, meaning we need to see at a resolution of ~6000 km on the surface. Proxima Centauri is ~4 light years away, meaning that this requires an angular resolution of 1.5e-10 radians or 30 microarcseconds. That's over 30,000 times smaller than the angular size of a human hair held at arms length!) To achieve 30 microarcsecond resolution with our optical interferometer operating at 600 nm (visible light), we need the two telescopes to be 4 km apart, which practically doesn't sound unfeasible. Alternatively, you could construct a 4 km telescope, but that's far bigger than any optical telescope we have now or in the near future (the biggest telescope in the next 20 years will be 40 meter in diameter).
  - kilroy123 10y ago
    Interesting, I would love to see a feasibility study done on this.
    - semaphoreP 10y ago
      NASA actually did do a feasibility study on the Terrestrial Planet Finder (https://en.wikipedia.org/wiki/Terrestrial_Planet_Finder https://en.wikipedia.org/wiki/Terrestrial_Planet_Finder) as a space-based telescope to find terrestial planets orbiting other stars, and one of the versions is an infrared interferometer flying in formation in space. Unfortunately, they never followed through with it (I'm guessing due to technical challenges).
ngoldbaum 10y ago
And here's the paper describing the discovery: http://www.eso.org/public/archives/releases/sciencepapers/eso1629/eso1629a.pdf http://www.eso.org/public/archives/releases/sciencepapers/es...
shmerl 10y ago
Is it feasible to send deep space probes to such planet? Let's say the probe is accelerated to high sub light speeds with ion thrusters. Can it reach it in some sensible time then?
- megalodon 10y ago
  Assuming the recently announced deep space travel project [1] works out and their estimates are correct (unlikely), it would take 20 years of preparation + 20 years of travel + 4 years of data transfer. Also mentioned in [1] is that if Voyager 1 was headed for Alpha Centauri it would take 70,000 years. [1] http://www.nytimes.com/2016/04/13/science/alpha-centauri-breakthrough-starshot-yuri-milner-stephen-hawking.html http://www.nytimes.com/2016/04/13/science/alpha-centauri-bre...
  - fluxquanta 10y ago
    Related question: If some other advanced civilization sent us one of these iPhone sized computers, do we have the technology to detect it before it zooms past our planet or burns up in our atmosphere?
  - shmerl 10y ago
    Good to know some are already trying to do that.
bordercases 10y ago
Pod Recovered
sakopov 10y ago
Posted this story when it came out a week ago but it got no traction. [1] This is quite exciting but as far as I understand we are not quite there in terms of technology to reach it within my lifetime. [1] https://news.ycombinator.com/item?id=12302489 https://news.ycombinator.com/item?id=12302489
- justplay 10y ago
  i see, next time i would say, to use simple title to get HN attention.
ommunist 10y ago
If there is oil on it, centaurian bloody dictatorship cannot be tolerated by progressive democratical forces.
thedangler 10y ago
So I guess we start sending light patters to that planet and wait 8 years for a response?
- excalibur 10y ago
  I think we started a long time ago. The planet is a new find, Proxima Centauri is not. If there were anyone there capable of responding, I think we would have heard from them by now.
  - GarrisonPrime 10y ago
    Assuming they'd be capable of detecting the signal. And able to interpret it. And willing to respond.
  - deleted 10y ago
    [deleted]
afreak 10y ago
Keep in mind that at best it would take maybe 1,000 years with current technology to get there with a probe or human-supporting ship. It would be highly unpopular however as it involves exploding nuclear bombs behind the craft to get it there that fast--that and it would probably cost trillions to build the thing.
- fapjacks 10y ago
  <Obligatory flamewar-starting "Em Drive" comment>
- DominikR 10y ago
  Actually the 1000 year number comes from Project Orion in the 1940ties and 50ties. https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls... An updated design from the 80ties calculated a time of 100 years: https://en.wikipedia.org/wiki/Project_Longshot https://en.wikipedia.org/wiki/Project_Longshot And a nuclear fusion design is calculated to achieve 12% of light speed, thereby reducing time to reach the fourth nearest sun system in 46 years. https://en.wikipedia.org/wiki/Project_Daedalus https://en.wikipedia.org/wiki/Project_Daedalus So there are concepts that could make unmanned interstellar travel possible, even within a humans life span, it's just that it costs so much and the incentive is pretty low compared to the incentive countries had for getting objects into space. (primarily military incentives - get spy satellites and nuclear warheads into space to not fall back behind adversaries) I believe that given a strong enough incentive humans could do it, no matter what current consensus is telling us. Humans set out to work on reaching outer space without even having a design on how this could be achieved and we did it anyway.
  - jnicholasp 10y ago
    50ties - Fifty-ties -- Fifties - 50s / 50's
    - DominikR 10y ago
      Thanks, English is not my native language. So what is correct, 50s or 50's?
taliesinb 10y ago
Wow, amazing result. And talk about synchronicity - just last night I watched an interesting 2015 talk about the search for planets around Alpha Centauri using the radial velocity technique: https://www.youtube.com/watch?v=eieBXGpNYyE https://www.youtube.com/watch?v=eieBXGpNYyE The speaker even mentioned the previous incorrect HARPS announcement, which was later found to be an artefact due to the windowing function they used - a pretty embarrassing mistake. This new finding involves a completely different period: 11.2 days instead of the previous 3.24 day signal. Also, link to the Nature paper for the lazy: http://www.eso.org/public/archives/releases/sciencepapers/eso1629/eso1629a.pdf http://www.eso.org/public/archives/releases/sciencepapers/es...
- WilliamDhalgren 10y ago
  If you mean the previous claim of there being an Alpha Centauri Bb planet, later retracted, then this new finding involves a completely different star, not just a different period. This is around Proxima Centauri, the previous one was around Alpha Centauri B. Proxima is a really really small red dwarf, just 12.3% the mass of sun, while Alpha Centauri B is a K-type star, ie somewhat smaller than sun but not that much; around 90% of Sun's mass (And there's also Alpha Centauri A, 10% more massive than the sun). We're not even 100% sure that Proxima is part of the Alpha Centauri system, though I gather it's considered highly likely - it's pretty distant from the Alpha Centauri system, some 15 000 AU (1 AU = distance between Sun and Earth), almost a quarter of a light year.
  - taliesinb 10y ago
    Yes, realized this and was editing my comment to reflect that but you beat me to it :). They did mention a previous signal from 2013, which got me confused with the spurious signal the SETI lecture mentioned.
    - WilliamDhalgren 10y ago
      heh, as you say; apparently there was a previous signal; reading the article about the find at centauri dreams, http://www.centauri-dreams.org/?p=36210 http://www.centauri-dreams.org/?p=36210 - and it does mention a pre-2016 Doppler signal with a period of 11.2 days around specifically Proxima, that was unconfirmed, and that this mission was to investigate that more closely. "The HARPS Pale Red Dot campaign was created to confirm or refute this 11.2-day signal" I'm just not sure if that's what the speaker in your video was talking about, of if the embarrasing mistake that was actually announced was the Alpha Centauri Bb planet (or maybe there were other candidates I didn't hear about); I'm gonna watch the lecture you linked and see. Thx for an interesting link, btw!
stormbrew 10y ago
Was there an error in an early version of this article? There are two comments in here saying 500ly away. Proxima is only ~4ly away.
lutusp 10y ago
This discovery will greatly increase interest in gigantic telescopes, to allow a closer look at the planet and its atmosphere.
dang 10y ago
Another good article: http://www.nature.com/news/earth-sized-planet-around-nearby-star-is-astronomy-dream-come-true-1.20445 http://www.nature.com/news/earth-sized-planet-around-nearby-... via https://news.ycombinator.com/item?id=12353448 https://news.ycombinator.com/item?id=12353448.
- throwaway_yy2Di 10y ago
  To piggyback on this, the Nature paper (which is paywalled) has a free preprint version here: http://www.eso.org/public/archives/releases/sciencepapers/eso1629/eso1629a.pdf http://www.eso.org/public/archives/releases/sciencepapers/es... (PDF)
withinrafael 10y ago
Melnorme are known to hang out around that system.
Cortez 10y ago
There's too many factors to say the zone may be habitable for life.
- ralusek 10y ago
  "may" being the word that makes it true.
kjell 10y ago
Just in time for the third book in Liu Cixin's space opera ("Remembrance of Earth's Past") to be released in english next month: https://www.goodreads.com/book/show/25451264-death-s-end https://www.goodreads.com/book/show/25451264-death-s-end Previously on HN: https://duckduckgo.com/?q=site%3Anews.ycombinator.com+cixin+liu&ia=web https://duckduckgo.com/?q=site%3Anews.ycombinator.com+cixin+... https://hn.algolia.com/?query=Cixin%20Liu&sort=byPopularity&prefix&page=0&dateRange=all&type=story https://hn.algolia.com/?query=Cixin%20Liu&sort=byPopularity&...
- shagie 10y ago
  And recently published Proxima about settlers on a planet around Proxima Cent. https://www.amazon.com/Proxima-Stephen-Baxter/dp/045146771X https://www.amazon.com/Proxima-Stephen-Baxter/dp/045146771X
  - godshatter 10y ago
    Finished Ultima a couple of weeks ago, didn't know it was the second in a series. I'm looking forward to reading Proxima when I can get to it on my list.
- jamesjyu 10y ago
  I got an early release of this, and it is fantastic.
  - the_rosentotter 10y ago
    Waiting eagerly.
    - ncallaway 10y ago
      Oh, what timing! I just finished the second book a couple of days ago. I had no idea the next book was coming out soon.
      - 10y ago
bcjordan 10y ago
Would it remain in a habitable state longer than Earth?
- throwaway_yy2Di 10y ago
  Yes, because the lifespan of low-powered red dwarfs is vastly longer than the sun's. The wiki page cites a figure of 4 trillion years (!) for Proxima: https://en.wikipedia.org/wiki/Proxima_Centauri https://en.wikipedia.org/wiki/Proxima_Centauri
- flashman 10y ago
  As with everything in astronomy: it depends. Just because the star is longer-lived than the Sun doesn't mean its planets will remain habitable as long. Small stars have planets that orbit close and become tidally locked, possibly losing their water and atmosphere in tens or hundreds of millions of years. It will be a long, long time until Proxima Centauri dies – four trillion years by one estimate[1] – but its planet may be dead already. Cheerfully, multicellular life on Earth only has somewhere between 600 and 800 million years left before the Sun gets too hot and all the carbon dioxide disappears from the atmosphere. But single-celled organisms will persist nearly another 3 billion years.[2] [1]https://en.wikipedia.org/wiki/Proxima_Centauri https://en.wikipedia.org/wiki/Proxima_Centauri [2]https://en.wikipedia.org/wiki/Timeline_of_the_far_future#Future_of_the_Earth.2C_the_Solar_System_and_the_Universe https://en.wikipedia.org/wiki/Timeline_of_the_far_future#Fut...
  - throwaway_yy2Di 10y ago
    ...tidally locked, possibly losing their water and atmosphere in tens or hundreds of millions of years. How would this happen?
sangd 10y ago
That will take the New Horizons 73,796 years to fly by.
ralusek 10y ago
Funny that there have been exoplanets found on so many stars, but our closest neighbor can still surprise us.
mjhoy 10y ago
The fun stuff is buried in footnote [4]: > The actual suitability of this kind of planet to support water and Earth-like life is a matter of intense but mostly theoretical debate. Major concerns that count against the presence of life are related to the closeness of the star. For example gravitational forces probably lock the same side of the planet in perpetual daylight, while the other side is in perpetual night. The planet's atmosphere might also slowly be evaporating or have more complex chemistry than Earth’s due to stronger ultraviolet and X-ray radiation, especially during the first billion years of the star’s life. However, none of the arguments has been proven conclusively and they are unlikely to be settled without direct observational evidence and characterisation of the planet’s atmosphere. Similar factors apply to the planets recently found around TRAPPIST-1.
- dmix 10y ago
  Now we can factor in "always sunny" or "always dark" to our simulations of what aliens might look like (maybe even two races/species from the same planet?).
  - rootbear 10y ago
    I'm almost certain I read an SF story with this premise. Two races on a tidally locked planet.
  - w-ll 10y ago
    Well, "always dark" is waiting for us at the bottom of the ocean.
- bshimmin 10y ago
  For example gravitational forces probably lock the same side of the planet in perpetual daylight, while the other side is in perpetual night. Should I admit on HN to having watched a Vin Diesel film? Pitch Black, anyone?
  - strictnein 10y ago
    Of course. Vin Diesel movies have their place and are fun. Pitch Black was great. Riddick is a good anti-hero.
Diederich 10y ago
Does anyone here have an idea of which kind of resolution https://en.wikipedia.org/wiki/James_Webb_Space_Telescope https://en.wikipedia.org/wiki/James_Webb_Space_Telescope will provide? I'm assuming that this little rock might not even occupy a single pixel, but I'd love to be wrong.
- Diederich 10y ago
  Answering my own question via the reddit AMA: https://www.reddit.com/r/askscience/comments/4zdkra/askscience_ama_series_we_have_discovered_an/d6uzf24 https://www.reddit.com/r/askscience/comments/4zdkra/askscien... Says we'd need about 30 milliarcseconds, while, as noted elsewhere, Webb provides 100. Damn!
- smeyer 10y ago
  The JWST has an angular resolution of 0.1 arc seconds (according to a quick google search). This means a pixel at a distance of a parsec will correspond to about 0.1 astronomical units, which is about 20 times the radius of the Sun. Of course, this doesn't mean that the telescope can't image light from a smaller planet, just that there would be no resolution to distinguish features on the planet itself. Similarly, even though lots of stars and other astronomical objects are too small to resolve, we can still see the light from them with telescopes (and our eyes).
  - ingenter 10y ago
    I'd like to add a few things: - 1 parsec ~~ 3.26 light years. - pixel coverage ~ angular resolution * distance. pixel coverage ~ 0.1 * AU / (distance / 3.26 light-years)
- stickydink 10y ago
  Q: Approx. how good will the resolution be when direct imaging exoplanets? (asked by @JakePeriphery) A: Resolution? JWST's cameras can image gas giant planets greater than a few AU from their stars. http://jwst.nasa.gov/faq_tweetchat3.html http://jwst.nasa.gov/faq_tweetchat3.html
natch 10y ago
What's super confusing to me is: If the planet is so much closer to its star, and the star is so much larger than ours, why does the artist's conception show the star as being so "small" (perceived size, not actual size) as viewed from the planet? Was the artist just not thinking straight that day, or am I missing something? Yes I understand it's an "artist's conception" but the question remains.
- zman0225 10y ago
  not too sure about how incorrect the artist's concept is, but we have to remember that Promixa Centauri is a red dward with about 1/10 the radius of our Sun.
  - natch 10y ago
    Ah maybe when the article said the star is "bigger" than the Sun it meant "more massive." Which could explain the apparent contradiction, if it was more massive and smaller in radius. Of course then it would be denser than the sun, which would have to be the case for all of this to make sense.
jomamaxx 10y ago
"Major concerns that count against the presence of life are related to the closeness of the star." I think the 'major concerns' are that we don't exactly know what 'life' is, and that since we have no information about any other 'biological entities' such as ourselves anywhere else, we can't entirely assume that it's a common thing. I suggest that if we find life out there, it will be very common. But it's not entirely plausible that this is the case. It's an interesting statistical game, made very difficult by the fact we don't fully grasp how 'we' became in the first place. I mean, we have the gist of it, but there's so much that remains unknown.
hoodoof 10y ago
Is any article ever published on an exoplanet in without speculating that it might harbor life?
- dragonwriter 10y ago
  > Is any article ever published on an exoplanet in without speculating that it might harbor life? Fairly common, as I recall, for articles about planets that either appear to be gas giants or appear to be outside of the "habitable zone".
- kowdermeister 10y ago
  No, it's mandatory. Just like articles about black holes has to mention "not even light" and articles about quantum entanglement has to mention "spooky action at a distance" ;)
thatha7777 10y ago
Sorry for the , but if you took a Space Shuttle to Proxima Centauri it'd take 160,865 years. http://www.wolframalpha.com/input/?i=distance+to+Proxima+Centauri+in+km+%2F+28300+kph http://www.wolframalpha.com/input/?i=distance+to+Proxima+Cen...
owenversteeg 10y ago
Although we can't image it with current technology (JWST and Hubble both have resolution of 100 milliarcseconds) we might be able to within a few years. IR inferometers will be able to give us some data in just a few years, and the E-ELT/TMT will also let us "image" it. The "image" won't be anything you can really look at (E-ELT has resolution one milliarcsecond) but it'll give us important data.
- superkuh 10y ago
  In the medium term a 22 GHz radio interferometer using the sun as a gravitational lens would be able to resolve 80 km diameter water clouds on Proxima b. This talk by the inventor of the concept for SETI purposes explains it pretty well: https://www.youtube.com/watch?v=ObvKVe5H8pc https://www.youtube.com/watch?v=ObvKVe5H8pc The real trick is getting out 600 AU to the gravitational focal line for the light opposite proxima centuari and staying with ~10m of it via station keeping. The only medium term solution to get out there in under 20 years are electrostatic solar sails. See Bruce Wiegmann of NASA Marshall Space Flight Center's talk from yesterday on the Heliopause Electrostatic Rapid Transit System. http://livestream.com/viewnow/NIAC2016/videos/133764483 http://livestream.com/viewnow/NIAC2016/videos/133764483
derflatulator 10y ago
But is everything on a cob?
mrfusion 10y ago
Has anyone considered this planet could actually be a smaller planet with a large moon tidally locked to each other?
ianai 10y ago
For some reason this really reminds me of Asimov's Nemesis book.
KamiCrit 10y ago
Well, sounds like it's time to spin up another Space Odyssey book. 4001 anyone?
- Jaruzel 10y ago
  After the awful 3001? Please... No. :(
misiti3780 10y ago
Nick Lane's book/hypothesis really change the way I think about life on other planets. His hypothesis is basically that the chances of Eukaryotic cells emerging from bacteria (via natural selection) are so rare (it only happened once in two billion years on our planet) that we really shouldnt expect to find intelligent life on other planets - rather the life we will most likely find will be small cells like bacteria and archaea, that lack a nucleus (and never get very big). He does a much better job of explaining why, but it is interesting nonetheless. [1] https://www.theguardian.com/books/2015/apr/22/the-vital-question-nick-lane-review-secret-life https://www.theguardian.com/books/2015/apr/22/the-vital-ques...
bikamonki 10y ago
Since we're all rolling out our best fiction here, here's mine: We'll get there animating matter by means of beaming laser instructions onto it. We just need to discover how we can move atoms by simply shinning a laser onto them, a controlled pulse of different light frequencies that allows us to arrange atoms in such way that they become tiny building blocks of nano-machines, like making pizza dough: twisting, throwing, rolling, until we have the right shape. Once the first Lego pieces are ready, we use the same laser to instill the energy required to move them. These animated nano-machines will then auto-assemble and become a bigger machine until we effectively, and remotely, build and operate a full-featured robot. Said bot will send back everything we need: images, audio, chemical reads, etc. Furthermore, our bot can build more bots and eventually build the laser that can be beamed into the next planet to repeat the process and expand colonization.
- FreeFull 10y ago
  Unfortunately, even laser light has too much divergence (due to intrinsic behaviour of waves) to remain one focused tight spot by the time it reaches Proxima Centauri, or even the outskirts of our solar system. https://en.wikipedia.org/wiki/Laser#The_light_emitted https://en.wikipedia.org/wiki/Laser#The_light_emitted does say that the rate of divergence is inversely proportional to the diameter of the beam, so maybe if we make the beam really wide, it could reach Proxima Centauri without spreading too much.. I don't know how wide that would have to be.
rubyfan 10y ago
We should send Matthew Mcconaughey there asap.
meganvito 10y ago
Ye, I am at an age too many untangile zeroes that I have no nexus.
cvarjas 10y ago
Two submitted articles on the habitability of Proxima Centauri b: http://www.ice.cat/personal/iribas/Proxima_b/publications.html http://www.ice.cat/personal/iribas/Proxima_b/publications.ht...
partycoder 10y ago
It's not only temperature, presence of water and distance to star. It's also a large variety of factors. For instance... what is the atmospheric pressure? boiling point of water is affected by atmospheric pressure. Even if temperature is low, if atmospheric pressure is also low, water would boil at a lower temperature. In Mars for instance, water boils all the time. Some people might say you can probably create more atmospheric pressure by terraforming the atmosphere. But not all planets can retain an atmosphere. Solar activity, planet magnetic field and gravity can affect that. Then, gamma ray exposure. Radiation can sterilize a planet. It would be good to measure what is it like there.
markingram 10y ago
Let's say the chance of Aliens visiting Earth is 1 in 1 vigintillion, then the chance of the Aliens being at similar levels of technological advancement as humans is 1 in 1 centillion... In other words, they are so advanced that they can visit us without us knowing, unless they wanted us to know. They can wipe us out without us knowing, unless they wanted us to know. I am so glad all these are still theoretical.
- StanislavPetrov 10y ago
  >In other words, they are so advanced that they can visit us without us knowing, unless they wanted us to know. They can wipe us out without us knowing, unless they wanted us to know. Just as likely they can wipe us out without caring if we know or knowing that we exist, no different then stepping on an ant as you walk to your car.
- inDigiNeous 10y ago
  It's kinda funny that almost always when talking about other races and levels of technological development, the issue of a more highly advance race killing us is raised. I would see it highly more probable, that if another life form has (and probably, definitely even, has) reached a state of technological development where they can travel to the stars and beyond, they would have already went through a phase in their development as a race, where they realized 'Hey, maybe it's not a good idea to kill ourselves or others, c'mon, let's work together, evolve and go further!' I could even speculate that this is one of the requirements of making it to a level of technological and spiritual development where we can unlock the secrets of the universe in mutual assurance that we are not afraid of killing ourselves every day, and save that energy for something more constructive, like building space ships..
  - onion2k 10y ago
    That would largely depend on their interactions with other planets before meeting us. If they've had bad experiences, to the point of almost being killed themselves, then they might well believe annihilating us or ignoring us is preferable to working with us. Self-preservation is a very powerful instinct in every species we've seen on Earth. Why wouldn't it be for aliens too?
mirekrusin 10y ago
Would moon also align its orbit? In the icy eyeball it could make some interesting tides like on the football stadium.
nxzero 10y ago
Makes me wonder for AI and robotic "life" what would be the best "habitat" for growth.
transfire 10y ago
This planet is "Nemesis". If you are an Asimov fan, you know why. Damn he was eerily prescient about this one.
- Alexey_Nigin 10y ago
  The planet in Nemesis had one major difference which may turn out to be crucial: it was not actually a planet. It was a moon. Since Proxima b is a planet, it is probably locked with one side always facing the sun. In Nemesis, Erythro was locked around the gas giant it was orbiting, but not locked around the star, allowing normal day-night cycle.
dghughes 10y ago
If the planet is tidally locked I say that may be good can you imagine an 11 day "year" but also rotating? It would be like living on the Scrambler carnival ride.
sampo 10y ago
Here is slides and video for a talk "Adaptive Optics Imaging of Extosolar Planets" from 2015. Especially the review of history of the study of exoplanets is amusing. When only our solar system was known, everyone believed in the theory of "inner rocky planet region, outer gas giant planet region". When astronomers finally started to have instruments to actually detect planets in other solar systems in the mid-1990s, almost none of the detected exoplanets fit the theory (slides 5-8). http://www.pppl.gov/events/colloquium-adaptive-optics-imaging-extosolar-planets http://www.pppl.gov/events/colloquium-adaptive-optics-imagin...
daveheq 10y ago
I read this days ago, in fact I heard about it from some YouTube conspiracy theorist just before that, saying NASA was covering it up when instead the scientific evidence just wasn't conclusive that it was actually a habitable planet if even a planet because it could have just been two stars' orbits or other rocky bodies.
justinzollars 10y ago
I hope we can get off of Earth.
oli5679 10y ago
Its hard to draw definitive conclusions when you're speculating from a sample of one! Imagine showing a child with no knowledge of animals a snake and asking her to describe what she thinks the other animals on earth are like and the habitats they occupy. I think there'd be a risk that she'd describe a range of snakes and possibly lizards, but wouldn't be able to imagine something radically different like a whale/eagle. That's the risk we run when our only sample is the earth.
DrNuke 10y ago
For the foreseeable future, terraforming of Mars is much more attainable than any going remote.
Dowwie 10y ago
and maybe the life on that planet just discovered us in the process
Symmetry 10y ago
I wouldn't hold out much hope for it being particularly habitable. Without the early development of life you don't have a high oxygen atmosphere for most of a planet's history. Without oxygen no ozone. Without ozone UV light breaks up water molecules high in the atmosphere and the planet loses hydrogen on the solar wind. And then you end up like Mars. In terms of planets to establish a colony on I'd actually look for ones a bit outside the traditional habitable zones. You'd need a bit more in terms of solar panels and heating but lacking hydrogen is a big handicap.
- elliotec 10y ago
  There's a hell of a lot that we don't know about the universe. What if there can be life within the restrictions you suggest? Or even more likely, what if there is something lifelike that doesn't constitute as life? Lots of questions and possibilities.
Pica_soO 10y ago
well obviously we need the world smallest factory gunned there, directly towards the star, slowing down on solar sails, drifting out into the local orb-equivalent, manufacturing drones and tight-beam equipment.

1187 points by Thorondor 10y ago

This is cool and all, but my question would be to what end? We can't know if there is water on it, life, or anything else about it really. We can't gauge it's atmosphere, it's 500 light years away so it's way too far to look at it. I guess it's cool to know that there are other planets the size of earth in a habitable zone, but with all the stars in all the galaxies, isn't it quite obvious that there would be some of these? Ok, so now we know there IS one at least, but now what?

api 10y ago

How big of a space telescope would we need to see this planet in any actual detail? One of my sci-fi fantasies is to take a photo of an extrasolar planet and see someone else's city lights. :) Of course if we could see that we could also probably detect their radio emissions, but seeing someone else's lights would somehow be cooler.

kyriakos 10y ago
I'm no expert but I'd say you need an orbiting telescope to do that.
themartorana 10y ago
At ~500 light years away, even if we did see lights, who would we be communicating with _now_? And would it be disappointing if we saw a technologically-similar civilization that hadn't contacted us yet, being 500 years ahead of us? Sometimes it's romantic to look up at stars that probably died a long time ago. Sometimes I hate that we can't see what's happening now.
- karmelapple 10y ago
  Where does the 500 light years number come from? Alpha Centauri is only 4.4 light years away from Earth.
  - ogrisel 10y ago
    This discovery is about Proxima Centauri which is slightly closer: 4.25 ly.
- bengarvey 10y ago
  It's only 4.25 light years away https://en.wikipedia.org/wiki/Proxima_Centauri https://en.wikipedia.org/wiki/Proxima_Centauri
- verandaguy 10y ago
  Why are people in this thread constantly citing 500 light-years? Proxima Centauri's 4 ly away, which, granted, isn't a walk in the park, but it's remarkably near to us.
- civilian 10y ago
  Why would a civilization be exactly 500 years ahead of us? While evolution is a powerful trend, I think there's so much randomness about... when their planet cooled off enough (and had enough alkaline vents) to support abiogenesis, when bacteria form eukaryotes, when eukaryotes become multi-cellular, when life moves out of the oceans, when plant-like organisms start producing fruit leading to animals that take advantage of the high-energy food source and are able to develop smart brains--- all of these events could happen +/- a million years from eachother. And that's assuming that their evolution of life followed a similar path! So worrying about a race having 500 years on us is just... a worry based on so many wrong assumptions.
evilduck 10y ago
That question pops up on /r/askscience fairly often. Here's one that does the math for the previously closest known Earthlike exoplanet (36ly) and Alpha Centauri (4.5ly). https://www.reddit.com/r/askscience/comments/137klp/will_there_be_space_telescopes_capable_of_taking/ https://www.reddit.com/r/askscience/comments/137klp/will_the...?
- Gravityloss 10y ago
  For starters, it doesn't seem impossible to build it, on earth or in space. You don't need a continuous mirror of that size. I wonder if any of the LIGO technology can be applied to optical telescopes? https://en.wikipedia.org/wiki/Aperture_synthesis https://en.wikipedia.org/wiki/Aperture_synthesis
throwanem 10y ago
> How big of a space telescope would we need to see this planet in any actual detail? Impossibly big. I'm sorry.
- TeMPOraL 10y ago
  From the link 'evilduck posted, it seems that's big indeed, but possibly big. 240km is a big thing, but within the realm of possibility; also I'm personally hoping someone will invent some magic mathematical trick around phased arrays or whatever, and cut that size by an order of magnitude or two :).
  - throwanem 10y ago
    240km is also what's required to resolve a feature no smaller than 100km across. I'm no mathematician and I am not equipped at the moment to pretend to be one, but to resolve a feature an order of magnitude smaller, I suspect you'd need a much larger instrument.
    - ianai 10y ago
      If I did the math correctly, it turns out to be ~2400km for 10km across (changing 100 to 10 in the eq). This could very easily be wrong as I only glanced through the comment. Think of it as Kirkian mathematics.
  - ianai 10y ago
    I would file 240km under very do-able. It's nothing like, say, a solar system sized particle accelerator.
    - throwanem 10y ago
      That simple? Well jeez, I don't know what I was even worried about. :D
darkerside 10y ago
Way cooler, because it would imply they share our visible light spectrum!
- wcoenen 10y ago
  It's not a coincidence that we can see in the 390 to 700 nm part of the spectrum. These are the wavelengths that pass through water most easily[1]. Any alien lifeforms which started their evolution in (illuminated) water could be expected to be sensitive to the same slice of the spectrum. [1] https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_water#/media/File:Absorption_spectrum_of_liquid_water.png https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_...
Thorondor 10y ago
The planet is about 0.05 AU from Proxima Centauri, meaning we need an angular resolution of about 1.9e-7 radians to even distinguish it from its host star. Is that realistic? In theory, an orbiting space telescope has a diffraction-limited resolution of approximately 1.22λ/D (λ = wavelength, D = aperture size). Modern image processing techniques can improve on this somewhat, but it makes a good order-of-magnitude estimate. Anyway, this formula tells us a 4-meter telescope has a maximum angular resolution of about 1.8e-7 radians at a typical visible light wavelength of 600 nm. That would be just good enough... except that we don't actually have a 4 meter orbiting space telescope. Resolving even large features on the planet would require a much larger telescope, probably kilometers or more. For ground based telescopes, the situation is even worse because of atmospheric effects. Despite being 10 meters in aperture, the Keck telescopes in Hawaii are limited to an angular resolution of about 2e-7 radians because of the atmosphere. However, there is reason to hope that the even larger European Extremely Large Telescope will have enough resolution (about 5e-8 radians? hard to tell from their official publications) to image Proxima b directly. https://www.eso.org/sci/meetings/2011/VLTI2011/presentations/Kissler-Patig.pdf https://www.eso.org/sci/meetings/2011/VLTI2011/presentations... Again, this is still not enough to resolve surface features. So, long story short the answer is unfortunately no at present. Maybe space-based manufacturing will let us build a big enough telescope someday?
- verandaguy 10y ago
  To put things in perspective, what was the angular resolution of Hubble's Ultra Deep Field measurements/photos? (keeping in mind that angular resolution isn't the only challenge here)
  - Thorondor 10y ago
    Hubble's angular resolution is about 0.05 arcsec = 2.4e-7 radians. And you're absolutely right that angular resolution isn't the only challenge here - some way of filtering out the extremely bright (relatively) light from the host star is needed as well, for starters.
- throwaway_yy2Di 10y ago
semaphoreP 10y ago
The most promising technique at this point is to use optical interferometry to resolve the surface of the planet. In this case, you will need two telescopes (likely in space) separated by a baseline distance, "d". The two telescopes will require extremely precise synchronization in both spatial position and timing so that the light they collect will interfere at precisely the right phase, but if this can be achieved, the angular resolution of such a telescope in radians is wavelength/d. An earth sized planet has a diameter of ~13,000 km. To "resolve the planet", we would need to be able to distinguish one half of the planet from the other, meaning we need to see at a resolution of ~6000 km on the surface. Proxima Centauri is ~4 light years away, meaning that this requires an angular resolution of 1.5e-10 radians or 30 microarcseconds. That's over 30,000 times smaller than the angular size of a human hair held at arms length!) To achieve 30 microarcsecond resolution with our optical interferometer operating at 600 nm (visible light), we need the two telescopes to be 4 km apart, which practically doesn't sound unfeasible. Alternatively, you could construct a 4 km telescope, but that's far bigger than any optical telescope we have now or in the near future (the biggest telescope in the next 20 years will be 40 meter in diameter).
- kilroy123 10y ago
  Interesting, I would love to see a feasibility study done on this.
  - semaphoreP 10y ago
    NASA actually did do a feasibility study on the Terrestrial Planet Finder (https://en.wikipedia.org/wiki/Terrestrial_Planet_Finder https://en.wikipedia.org/wiki/Terrestrial_Planet_Finder) as a space-based telescope to find terrestial planets orbiting other stars, and one of the versions is an infrared interferometer flying in formation in space. Unfortunately, they never followed through with it (I'm guessing due to technical challenges).

ngoldbaum 10y ago

And here's the paper describing the discovery: http://www.eso.org/public/archives/releases/sciencepapers/eso1629/eso1629a.pdf http://www.eso.org/public/archives/releases/sciencepapers/es...

shmerl 10y ago

Is it feasible to send deep space probes to such planet? Let's say the probe is accelerated to high sub light speeds with ion thrusters. Can it reach it in some sensible time then?

megalodon 10y ago
Assuming the recently announced deep space travel project [1] works out and their estimates are correct (unlikely), it would take 20 years of preparation + 20 years of travel + 4 years of data transfer. Also mentioned in [1] is that if Voyager 1 was headed for Alpha Centauri it would take 70,000 years. [1] http://www.nytimes.com/2016/04/13/science/alpha-centauri-breakthrough-starshot-yuri-milner-stephen-hawking.html http://www.nytimes.com/2016/04/13/science/alpha-centauri-bre...
- fluxquanta 10y ago
  Related question: If some other advanced civilization sent us one of these iPhone sized computers, do we have the technology to detect it before it zooms past our planet or burns up in our atmosphere?
- shmerl 10y ago
  Good to know some are already trying to do that.

bordercases 10y ago

Pod Recovered

sakopov 10y ago

Posted this story when it came out a week ago but it got no traction. [1] This is quite exciting but as far as I understand we are not quite there in terms of technology to reach it within my lifetime. [1] https://news.ycombinator.com/item?id=12302489 https://news.ycombinator.com/item?id=12302489

justplay 10y ago
i see, next time i would say, to use simple title to get HN attention.

ommunist 10y ago

If there is oil on it, centaurian bloody dictatorship cannot be tolerated by progressive democratical forces.

thedangler 10y ago

So I guess we start sending light patters to that planet and wait 8 years for a response?

excalibur 10y ago
I think we started a long time ago. The planet is a new find, Proxima Centauri is not. If there were anyone there capable of responding, I think we would have heard from them by now.
- GarrisonPrime 10y ago
  Assuming they'd be capable of detecting the signal. And able to interpret it. And willing to respond.
- deleted 10y ago
  [deleted]

afreak 10y ago

Keep in mind that at best it would take maybe 1,000 years with current technology to get there with a probe or human-supporting ship. It would be highly unpopular however as it involves exploding nuclear bombs behind the craft to get it there that fast--that and it would probably cost trillions to build the thing.

fapjacks 10y ago
<Obligatory flamewar-starting "Em Drive" comment>
DominikR 10y ago
Actually the 1000 year number comes from Project Orion in the 1940ties and 50ties. https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls... An updated design from the 80ties calculated a time of 100 years: https://en.wikipedia.org/wiki/Project_Longshot https://en.wikipedia.org/wiki/Project_Longshot And a nuclear fusion design is calculated to achieve 12% of light speed, thereby reducing time to reach the fourth nearest sun system in 46 years. https://en.wikipedia.org/wiki/Project_Daedalus https://en.wikipedia.org/wiki/Project_Daedalus So there are concepts that could make unmanned interstellar travel possible, even within a humans life span, it's just that it costs so much and the incentive is pretty low compared to the incentive countries had for getting objects into space. (primarily military incentives - get spy satellites and nuclear warheads into space to not fall back behind adversaries) I believe that given a strong enough incentive humans could do it, no matter what current consensus is telling us. Humans set out to work on reaching outer space without even having a design on how this could be achieved and we did it anyway.
- jnicholasp 10y ago
  50ties - Fifty-ties -- Fifties - 50s / 50's
  - DominikR 10y ago
    Thanks, English is not my native language. So what is correct, 50s or 50's?

taliesinb 10y ago

Wow, amazing result. And talk about synchronicity - just last night I watched an interesting 2015 talk about the search for planets around Alpha Centauri using the radial velocity technique: https://www.youtube.com/watch?v=eieBXGpNYyE https://www.youtube.com/watch?v=eieBXGpNYyE The speaker even mentioned the previous incorrect HARPS announcement, which was later found to be an artefact due to the windowing function they used - a pretty embarrassing mistake. This new finding involves a completely different period: 11.2 days instead of the previous 3.24 day signal. Also, link to the Nature paper for the lazy: http://www.eso.org/public/archives/releases/sciencepapers/eso1629/eso1629a.pdf http://www.eso.org/public/archives/releases/sciencepapers/es...

WilliamDhalgren 10y ago
If you mean the previous claim of there being an Alpha Centauri Bb planet, later retracted, then this new finding involves a completely different star, not just a different period. This is around Proxima Centauri, the previous one was around Alpha Centauri B. Proxima is a really really small red dwarf, just 12.3% the mass of sun, while Alpha Centauri B is a K-type star, ie somewhat smaller than sun but not that much; around 90% of Sun's mass (And there's also Alpha Centauri A, 10% more massive than the sun). We're not even 100% sure that Proxima is part of the Alpha Centauri system, though I gather it's considered highly likely - it's pretty distant from the Alpha Centauri system, some 15 000 AU (1 AU = distance between Sun and Earth), almost a quarter of a light year.
- taliesinb 10y ago
  Yes, realized this and was editing my comment to reflect that but you beat me to it :). They did mention a previous signal from 2013, which got me confused with the spurious signal the SETI lecture mentioned.
  - WilliamDhalgren 10y ago
    heh, as you say; apparently there was a previous signal; reading the article about the find at centauri dreams, http://www.centauri-dreams.org/?p=36210 http://www.centauri-dreams.org/?p=36210 - and it does mention a pre-2016 Doppler signal with a period of 11.2 days around specifically Proxima, that was unconfirmed, and that this mission was to investigate that more closely. "The HARPS Pale Red Dot campaign was created to confirm or refute this 11.2-day signal" I'm just not sure if that's what the speaker in your video was talking about, of if the embarrasing mistake that was actually announced was the Alpha Centauri Bb planet (or maybe there were other candidates I didn't hear about); I'm gonna watch the lecture you linked and see. Thx for an interesting link, btw!

stormbrew 10y ago

Was there an error in an early version of this article? There are two comments in here saying 500ly away. Proxima is only ~4ly away.

lutusp 10y ago

This discovery will greatly increase interest in gigantic telescopes, to allow a closer look at the planet and its atmosphere.

dang 10y ago

Another good article: http://www.nature.com/news/earth-sized-planet-around-nearby-star-is-astronomy-dream-come-true-1.20445 http://www.nature.com/news/earth-sized-planet-around-nearby-... via https://news.ycombinator.com/item?id=12353448 https://news.ycombinator.com/item?id=12353448.

throwaway_yy2Di 10y ago
To piggyback on this, the Nature paper (which is paywalled) has a free preprint version here: http://www.eso.org/public/archives/releases/sciencepapers/eso1629/eso1629a.pdf http://www.eso.org/public/archives/releases/sciencepapers/es... (PDF)

withinrafael 10y ago

Melnorme are known to hang out around that system.

Cortez 10y ago

There's too many factors to say the zone may be habitable for life.

ralusek 10y ago
"may" being the word that makes it true.

kjell 10y ago

Just in time for the third book in Liu Cixin's space opera ("Remembrance of Earth's Past") to be released in english next month: https://www.goodreads.com/book/show/25451264-death-s-end https://www.goodreads.com/book/show/25451264-death-s-end Previously on HN: https://duckduckgo.com/?q=site%3Anews.ycombinator.com+cixin+liu&ia=web https://duckduckgo.com/?q=site%3Anews.ycombinator.com+cixin+... https://hn.algolia.com/?query=Cixin%20Liu&sort=byPopularity&prefix&page=0&dateRange=all&type=story https://hn.algolia.com/?query=Cixin%20Liu&sort=byPopularity&...

shagie 10y ago
And recently published Proxima about settlers on a planet around Proxima Cent. https://www.amazon.com/Proxima-Stephen-Baxter/dp/045146771X https://www.amazon.com/Proxima-Stephen-Baxter/dp/045146771X
- godshatter 10y ago
  Finished Ultima a couple of weeks ago, didn't know it was the second in a series. I'm looking forward to reading Proxima when I can get to it on my list.
jamesjyu 10y ago
I got an early release of this, and it is fantastic.
- the_rosentotter 10y ago
  Waiting eagerly.
  - ncallaway 10y ago
    Oh, what timing! I just finished the second book a couple of days ago. I had no idea the next book was coming out soon.
    - 10y ago

bcjordan 10y ago

Would it remain in a habitable state longer than Earth?

throwaway_yy2Di 10y ago
Yes, because the lifespan of low-powered red dwarfs is vastly longer than the sun's. The wiki page cites a figure of 4 trillion years (!) for Proxima: https://en.wikipedia.org/wiki/Proxima_Centauri https://en.wikipedia.org/wiki/Proxima_Centauri
flashman 10y ago
As with everything in astronomy: it depends. Just because the star is longer-lived than the Sun doesn't mean its planets will remain habitable as long. Small stars have planets that orbit close and become tidally locked, possibly losing their water and atmosphere in tens or hundreds of millions of years. It will be a long, long time until Proxima Centauri dies – four trillion years by one estimate[1] – but its planet may be dead already. Cheerfully, multicellular life on Earth only has somewhere between 600 and 800 million years left before the Sun gets too hot and all the carbon dioxide disappears from the atmosphere. But single-celled organisms will persist nearly another 3 billion years.[2] [1]https://en.wikipedia.org/wiki/Proxima_Centauri https://en.wikipedia.org/wiki/Proxima_Centauri [2]https://en.wikipedia.org/wiki/Timeline_of_the_far_future#Future_of_the_Earth.2C_the_Solar_System_and_the_Universe https://en.wikipedia.org/wiki/Timeline_of_the_far_future#Fut...
- throwaway_yy2Di 10y ago
  ...tidally locked, possibly losing their water and atmosphere in tens or hundreds of millions of years. How would this happen?

sangd 10y ago

That will take the New Horizons 73,796 years to fly by.

ralusek 10y ago

Funny that there have been exoplanets found on so many stars, but our closest neighbor can still surprise us.

mjhoy 10y ago

The fun stuff is buried in footnote [4]: > The actual suitability of this kind of planet to support water and Earth-like life is a matter of intense but mostly theoretical debate. Major concerns that count against the presence of life are related to the closeness of the star. For example gravitational forces probably lock the same side of the planet in perpetual daylight, while the other side is in perpetual night. The planet's atmosphere might also slowly be evaporating or have more complex chemistry than Earth’s due to stronger ultraviolet and X-ray radiation, especially during the first billion years of the star’s life. However, none of the arguments has been proven conclusively and they are unlikely to be settled without direct observational evidence and characterisation of the planet’s atmosphere. Similar factors apply to the planets recently found around TRAPPIST-1.

dmix 10y ago
Now we can factor in "always sunny" or "always dark" to our simulations of what aliens might look like (maybe even two races/species from the same planet?).
- rootbear 10y ago
  I'm almost certain I read an SF story with this premise. Two races on a tidally locked planet.
- w-ll 10y ago
  Well, "always dark" is waiting for us at the bottom of the ocean.
bshimmin 10y ago
For example gravitational forces probably lock the same side of the planet in perpetual daylight, while the other side is in perpetual night. Should I admit on HN to having watched a Vin Diesel film? Pitch Black, anyone?
- strictnein 10y ago
  Of course. Vin Diesel movies have their place and are fun. Pitch Black was great. Riddick is a good anti-hero.

Diederich 10y ago

Does anyone here have an idea of which kind of resolution https://en.wikipedia.org/wiki/James_Webb_Space_Telescope https://en.wikipedia.org/wiki/James_Webb_Space_Telescope will provide? I'm assuming that this little rock might not even occupy a single pixel, but I'd love to be wrong.

Diederich 10y ago
Answering my own question via the reddit AMA: https://www.reddit.com/r/askscience/comments/4zdkra/askscience_ama_series_we_have_discovered_an/d6uzf24 https://www.reddit.com/r/askscience/comments/4zdkra/askscien... Says we'd need about 30 milliarcseconds, while, as noted elsewhere, Webb provides 100. Damn!
smeyer 10y ago
The JWST has an angular resolution of 0.1 arc seconds (according to a quick google search). This means a pixel at a distance of a parsec will correspond to about 0.1 astronomical units, which is about 20 times the radius of the Sun. Of course, this doesn't mean that the telescope can't image light from a smaller planet, just that there would be no resolution to distinguish features on the planet itself. Similarly, even though lots of stars and other astronomical objects are too small to resolve, we can still see the light from them with telescopes (and our eyes).
- ingenter 10y ago
  I'd like to add a few things: - 1 parsec ~~ 3.26 light years. - pixel coverage ~ angular resolution * distance. pixel coverage ~ 0.1 * AU / (distance / 3.26 light-years)
stickydink 10y ago
Q: Approx. how good will the resolution be when direct imaging exoplanets? (asked by @JakePeriphery) A: Resolution? JWST's cameras can image gas giant planets greater than a few AU from their stars. http://jwst.nasa.gov/faq_tweetchat3.html http://jwst.nasa.gov/faq_tweetchat3.html

natch 10y ago

What's super confusing to me is: If the planet is so much closer to its star, and the star is so much larger than ours, why does the artist's conception show the star as being so "small" (perceived size, not actual size) as viewed from the planet? Was the artist just not thinking straight that day, or am I missing something? Yes I understand it's an "artist's conception" but the question remains.

zman0225 10y ago
not too sure about how incorrect the artist's concept is, but we have to remember that Promixa Centauri is a red dward with about 1/10 the radius of our Sun.
- natch 10y ago
  Ah maybe when the article said the star is "bigger" than the Sun it meant "more massive." Which could explain the apparent contradiction, if it was more massive and smaller in radius. Of course then it would be denser than the sun, which would have to be the case for all of this to make sense.

jomamaxx 10y ago

"Major concerns that count against the presence of life are related to the closeness of the star." I think the 'major concerns' are that we don't exactly know what 'life' is, and that since we have no information about any other 'biological entities' such as ourselves anywhere else, we can't entirely assume that it's a common thing. I suggest that if we find life out there, it will be very common. But it's not entirely plausible that this is the case. It's an interesting statistical game, made very difficult by the fact we don't fully grasp how 'we' became in the first place. I mean, we have the gist of it, but there's so much that remains unknown.

hoodoof 10y ago

Is any article ever published on an exoplanet in without speculating that it might harbor life?

dragonwriter 10y ago
> Is any article ever published on an exoplanet in without speculating that it might harbor life? Fairly common, as I recall, for articles about planets that either appear to be gas giants or appear to be outside of the "habitable zone".
kowdermeister 10y ago
No, it's mandatory. Just like articles about black holes has to mention "not even light" and articles about quantum entanglement has to mention "spooky action at a distance" ;)

thatha7777 10y ago

Sorry for the , but if you took a Space Shuttle to Proxima Centauri it'd take 160,865 years. http://www.wolframalpha.com/input/?i=distance+to+Proxima+Centauri+in+km+%2F+28300+kph http://www.wolframalpha.com/input/?i=distance+to+Proxima+Cen...

owenversteeg 10y ago

Although we can't image it with current technology (JWST and Hubble both have resolution of 100 milliarcseconds) we might be able to within a few years. IR inferometers will be able to give us some data in just a few years, and the E-ELT/TMT will also let us "image" it. The "image" won't be anything you can really look at (E-ELT has resolution one milliarcsecond) but it'll give us important data.

superkuh 10y ago
In the medium term a 22 GHz radio interferometer using the sun as a gravitational lens would be able to resolve 80 km diameter water clouds on Proxima b. This talk by the inventor of the concept for SETI purposes explains it pretty well: https://www.youtube.com/watch?v=ObvKVe5H8pc https://www.youtube.com/watch?v=ObvKVe5H8pc The real trick is getting out 600 AU to the gravitational focal line for the light opposite proxima centuari and staying with ~10m of it via station keeping. The only medium term solution to get out there in under 20 years are electrostatic solar sails. See Bruce Wiegmann of NASA Marshall Space Flight Center's talk from yesterday on the Heliopause Electrostatic Rapid Transit System. http://livestream.com/viewnow/NIAC2016/videos/133764483 http://livestream.com/viewnow/NIAC2016/videos/133764483

derflatulator 10y ago

But is everything on a cob?

mrfusion 10y ago

Has anyone considered this planet could actually be a smaller planet with a large moon tidally locked to each other?

ianai 10y ago

For some reason this really reminds me of Asimov's Nemesis book.

KamiCrit 10y ago

Well, sounds like it's time to spin up another Space Odyssey book. 4001 anyone?

Jaruzel 10y ago
After the awful 3001? Please... No. :(

misiti3780 10y ago

Nick Lane's book/hypothesis really change the way I think about life on other planets. His hypothesis is basically that the chances of Eukaryotic cells emerging from bacteria (via natural selection) are so rare (it only happened once in two billion years on our planet) that we really shouldnt expect to find intelligent life on other planets - rather the life we will most likely find will be small cells like bacteria and archaea, that lack a nucleus (and never get very big). He does a much better job of explaining why, but it is interesting nonetheless. [1] https://www.theguardian.com/books/2015/apr/22/the-vital-question-nick-lane-review-secret-life https://www.theguardian.com/books/2015/apr/22/the-vital-ques...

bikamonki 10y ago

Since we're all rolling out our best fiction here, here's mine: We'll get there animating matter by means of beaming laser instructions onto it. We just need to discover how we can move atoms by simply shinning a laser onto them, a controlled pulse of different light frequencies that allows us to arrange atoms in such way that they become tiny building blocks of nano-machines, like making pizza dough: twisting, throwing, rolling, until we have the right shape. Once the first Lego pieces are ready, we use the same laser to instill the energy required to move them. These animated nano-machines will then auto-assemble and become a bigger machine until we effectively, and remotely, build and operate a full-featured robot. Said bot will send back everything we need: images, audio, chemical reads, etc. Furthermore, our bot can build more bots and eventually build the laser that can be beamed into the next planet to repeat the process and expand colonization.

FreeFull 10y ago
Unfortunately, even laser light has too much divergence (due to intrinsic behaviour of waves) to remain one focused tight spot by the time it reaches Proxima Centauri, or even the outskirts of our solar system. https://en.wikipedia.org/wiki/Laser#The_light_emitted https://en.wikipedia.org/wiki/Laser#The_light_emitted does say that the rate of divergence is inversely proportional to the diameter of the beam, so maybe if we make the beam really wide, it could reach Proxima Centauri without spreading too much.. I don't know how wide that would have to be.

rubyfan 10y ago

We should send Matthew Mcconaughey there asap.

meganvito 10y ago

Ye, I am at an age too many untangile zeroes that I have no nexus.

cvarjas 10y ago

Two submitted articles on the habitability of Proxima Centauri b: http://www.ice.cat/personal/iribas/Proxima_b/publications.html http://www.ice.cat/personal/iribas/Proxima_b/publications.ht...

partycoder 10y ago

It's not only temperature, presence of water and distance to star. It's also a large variety of factors. For instance... what is the atmospheric pressure? boiling point of water is affected by atmospheric pressure. Even if temperature is low, if atmospheric pressure is also low, water would boil at a lower temperature. In Mars for instance, water boils all the time. Some people might say you can probably create more atmospheric pressure by terraforming the atmosphere. But not all planets can retain an atmosphere. Solar activity, planet magnetic field and gravity can affect that. Then, gamma ray exposure. Radiation can sterilize a planet. It would be good to measure what is it like there.

markingram 10y ago

Let's say the chance of Aliens visiting Earth is 1 in 1 vigintillion, then the chance of the Aliens being at similar levels of technological advancement as humans is 1 in 1 centillion... In other words, they are so advanced that they can visit us without us knowing, unless they wanted us to know. They can wipe us out without us knowing, unless they wanted us to know. I am so glad all these are still theoretical.

StanislavPetrov 10y ago
>In other words, they are so advanced that they can visit us without us knowing, unless they wanted us to know. They can wipe us out without us knowing, unless they wanted us to know. Just as likely they can wipe us out without caring if we know or knowing that we exist, no different then stepping on an ant as you walk to your car.
inDigiNeous 10y ago
It's kinda funny that almost always when talking about other races and levels of technological development, the issue of a more highly advance race killing us is raised. I would see it highly more probable, that if another life form has (and probably, definitely even, has) reached a state of technological development where they can travel to the stars and beyond, they would have already went through a phase in their development as a race, where they realized 'Hey, maybe it's not a good idea to kill ourselves or others, c'mon, let's work together, evolve and go further!' I could even speculate that this is one of the requirements of making it to a level of technological and spiritual development where we can unlock the secrets of the universe in mutual assurance that we are not afraid of killing ourselves every day, and save that energy for something more constructive, like building space ships..
- onion2k 10y ago
  That would largely depend on their interactions with other planets before meeting us. If they've had bad experiences, to the point of almost being killed themselves, then they might well believe annihilating us or ignoring us is preferable to working with us. Self-preservation is a very powerful instinct in every species we've seen on Earth. Why wouldn't it be for aliens too?

mirekrusin 10y ago

Would moon also align its orbit? In the icy eyeball it could make some interesting tides like on the football stadium.

nxzero 10y ago

Makes me wonder for AI and robotic "life" what would be the best "habitat" for growth.

transfire 10y ago

This planet is "Nemesis". If you are an Asimov fan, you know why. Damn he was eerily prescient about this one.

Alexey_Nigin 10y ago
The planet in Nemesis had one major difference which may turn out to be crucial: it was not actually a planet. It was a moon. Since Proxima b is a planet, it is probably locked with one side always facing the sun. In Nemesis, Erythro was locked around the gas giant it was orbiting, but not locked around the star, allowing normal day-night cycle.

dghughes 10y ago

If the planet is tidally locked I say that may be good can you imagine an 11 day "year" but also rotating? It would be like living on the Scrambler carnival ride.

sampo 10y ago

Here is slides and video for a talk "Adaptive Optics Imaging of Extosolar Planets" from 2015. Especially the review of history of the study of exoplanets is amusing. When only our solar system was known, everyone believed in the theory of "inner rocky planet region, outer gas giant planet region". When astronomers finally started to have instruments to actually detect planets in other solar systems in the mid-1990s, almost none of the detected exoplanets fit the theory (slides 5-8). http://www.pppl.gov/events/colloquium-adaptive-optics-imaging-extosolar-planets http://www.pppl.gov/events/colloquium-adaptive-optics-imagin...

daveheq 10y ago

I read this days ago, in fact I heard about it from some YouTube conspiracy theorist just before that, saying NASA was covering it up when instead the scientific evidence just wasn't conclusive that it was actually a habitable planet if even a planet because it could have just been two stars' orbits or other rocky bodies.

justinzollars 10y ago

I hope we can get off of Earth.

oli5679 10y ago

Its hard to draw definitive conclusions when you're speculating from a sample of one! Imagine showing a child with no knowledge of animals a snake and asking her to describe what she thinks the other animals on earth are like and the habitats they occupy. I think there'd be a risk that she'd describe a range of snakes and possibly lizards, but wouldn't be able to imagine something radically different like a whale/eagle. That's the risk we run when our only sample is the earth.

DrNuke 10y ago

For the foreseeable future, terraforming of Mars is much more attainable than any going remote.

Dowwie 10y ago

and maybe the life on that planet just discovered us in the process

Symmetry 10y ago

I wouldn't hold out much hope for it being particularly habitable. Without the early development of life you don't have a high oxygen atmosphere for most of a planet's history. Without oxygen no ozone. Without ozone UV light breaks up water molecules high in the atmosphere and the planet loses hydrogen on the solar wind. And then you end up like Mars. In terms of planets to establish a colony on I'd actually look for ones a bit outside the traditional habitable zones. You'd need a bit more in terms of solar panels and heating but lacking hydrogen is a big handicap.

elliotec 10y ago
There's a hell of a lot that we don't know about the universe. What if there can be life within the restrictions you suggest? Or even more likely, what if there is something lifelike that doesn't constitute as life? Lots of questions and possibilities.

Pica_soO 10y ago

well obviously we need the world smallest factory gunned there, directly towards the star, slowing down on solar sails, drifting out into the local orb-equivalent, manufacturing drones and tight-beam equipment.