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NASA / msnbc.com
Planetary scientists are working on equations to assess how habitable a given planet might be.
Planet-hunters say they've developed a relatively simple method for determining how livable a faraway world might be, and they've used the formula to identify a top candidate: a super-Earth that's 36 light-years away.
The research paper was submitted to the journal Astronomy and Astrophysics just two weeks ago, but it's quickly making the rounds among those who follow the accelerating search for planets beyond our solar system. The big reason for all the interest is that the paper points to a new prospect for the short list of potentially habitable planets: HD 85512 b, a world that's at least 3.6 times as massive as Earth, circling an orange star in the constellation Vela.
The authors — Lisa Kaltenegger of the Harvard-Smithsonian Center for Astrophysics, and Stephane Udry and Francesco Pepe of the University of Geneva — rank the extrasolar planet right up there with Gliese 581d, a prime prospect for habitability that is 20 light-years from Earth. "HD 85512 b is, with Gl 581d, the best candidate for exploring habitability to date, a planet on the edge of habitability," they say.
The paper uses HD 85512 b as a test case for a set of equations aimed at assessing how livable a particular planet might be, based on its orbital parameters, how much radiation it gets from its parent sun and the nature of its atmosphere. HD 85512 b's minimum mass and orbital parameters were published only recently, based on data from the HARPS-Upgrade GTO planet search. The world orbits a star that is significantly dimmer than our own sun, at a distance of 0.26 AU — which is within Mercury's orbit in our solar system. It makes one full orbit every 58.4 Earth days, the researchers report.
The researchers assume that HD 85512 b is a rocky planet with an Earthlike atmosphere containing water vapor, carbon dioxide and nitrogen. If that's the case, and if more than half the planet is covered by clouds, then it "could be potentially habitable," they say.
Is there a way to resolve those "ifs"? Comparing the planet's mass with its size could tell astronomers whether its composition is more like Neptune's or Earth's. But to study its atmosphere, we're going to need a bigger telescope.
Here's how Kaltenegger explained the challenge to Skymania News: "As to whether it is really habitable, we’ll need a spectrum to tell that — direct imaging would be the ticket. With a direct imaging mission we could detect if it looks habitable. We could detect clouds if we had a big enough telescope in space."
It could be a long time before there's a telescope (or an interferometer) big enough to take on that job. But even now, Kaltenegger and her colleagues say that their research provides "a simple set of parameters which can be used for evaluating current and future planet candidates ... for their potential habitability."
How long will it take to whip up a top-ten list for extrasolar emigration? Weigh in with your comments below.
More about habitable planets:
- Astrobiologists seek a new equation for life
- Did cosmic collisions make habitable planets rare?
- NASA spots scores of potentially livable worlds
- Case builds for habitable alien planet
- 'Dead' planets might be livable after all
- Interactive: The search for other planets
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.
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The first group sent -- to explore and in fact, -- colonize would be a group headed to a brave new world. Say we launced a 100 people and then would only get word from them 80-120 years later. By then - they would have been through a few generations on the ship and may not even be all that interested in talking to us..
Drake's Equation indicates to me that life elsewhere is very, very close to a statistical certainty. Please keep in mind that the scientific and space exploration community have only just begun to build a fact based body of observations and discoveries that becomes more compelling with each decade. Each new discovery or clue builds on previous discoveries, each clarifying and refining the cosmic model represented by the variables in Dr. Frank Drake's famous equation. This discovery in many tiny steps is called the scientific method.
Advancement in unmanned probes, return missions, space based telescopes and computer created planetary models and scenarios will only hasten the day that we WILL finally know for sure that we are not alone. Indeed, because the Rev. Billy Bob and his obnoxious, slogan shouting flock will continue trying to pollute and pervert science with their mindless dogma, the revelation will happen quietly at first - recognized and verified by dedicated scientists and critical thinkers.
Indeed, the greatest discovery in the history of humanity will not come riding on fire from the heavens. No, the scientific confirmation will likely be delivered by the irrefutable detection of a tiny, insignificant micro-organism (alive or fossilized) on one of our solar system planets or moons. Then, the floodgates of scientific speculation and hypothesis will open and we will have taken another "giant leap for mankind".
People shouldn't get so down on humanity, true there are some that would make their mother cringe, yet there are the majority who are very decent, most making a living under difficult circumstances. What people need is a government that supports all the people, not the wealthy few.
Its funny how we seem to think that things are impossible until we figure it out, then it becomes possible. I suspect that when we discover microbial life on mars or elsewhere, then it will be ok to say, oh, it must be everywhere else. Intelligent life can't exist out there until we, almighty humans discover it first! Then it will be ok for it to be out there. Once we break through the time speed of light barrier, then it will be ok to assume other life forms may have used it to get here. But not until we say its ok.
My guess is this. Intelligent life is out there. Some of that life is thousands of years in advance of us. Some of that life is or has been here. Probably thousands of years ago, it didn't wait until I understood that it could exist, It developed wether I thought so or not. If we are not seeing this life here or its past evidence, than its probably for a really really good reason.
We are crazy killing machines ,best to stay undetected and just study from afar!
By figuring out how to do it, we prove that it is possible. In the long history of human ideas, 99.99% of all the ideas which humans thought were impossible, turned out to be, yes, actually impossible, and the naysayers were right. Only a tiny minority of these ideas turned out to be possible after all. So it makes sense to err on the side of caution in the beginning. This is particularly true when we have to make decisions with real-world consequences, such as the distribution of limited resources in the pursuit of such ideas, resources which are also needed for other things. A 1:10000 odds ratio isn't that hot. Perhaps you could justify putting a few dollars into it, if the potential payoff is truly huge, but you wouldn't be wise to sink your entire life savings into it. And this is, in the end, what we actually do. We invest a little bit in these big ideas, but hold off on committing large funds of resources and effort until we have more evidence to believe that it will actually work.
Intelligent life thousands of years in advance of us would have no cause to fear us, even if we are crazy killing machines, anymore than we have cause to fear those crazy killing machines scurrying under our feet, the ants. Sure a sting or bite here or there might hurt, and a particularly unlucky or incautious individual might even die, but our civilization as a whole is not in danger.
And they would have no more cause to deliberately hide their presence, or disguise their incidental activities, from us, as we would bother to hide our own presence form the ants.
If a civilization that old and that powerful really existed close enough to us in space to actually be meaningful, we would know already. Perhaps we wouldn't actually recognize it precisely, or understand what exactly was going on, but we'd see something, and we'd be able to tell that this something was out of the ordinary, and not consistent with a natural phenomenon.
It's 36 light years away. That means at the speed of light (186,000 mps), it would take 36 years. That means that the planet is: 211,165,056,000,000 miles away (that's 211 trillion miles folks).
But, the fastest rocket we've ever made only travels at about 35,000 miles per HOUR, so a trip like that would take: 19,131.43 YEARS for us with today's technology.
Current VASIMR designs can theoretically reach a velocity of 300 km/sec or 1,080,000 km/hr. That would reduce the trip time quite a bit.
Also, it's thought that there might be room for significant improvement in the VASIMR design.
Still, it's unlikely that we'd reach any nearby stars in a reasonable amount of time without achieving a good percentage of light speed.
Rockets aren't going to get us anywhere except from one planet to another within a single solar system. The whole concept of "rocket" (at least by itself) is doomed by physics for interstellar travel. Even the speed of light is too slow to create an interstellar society. Incredibly slow, in fact. We need a breakthrough, but not just a scientific breakthrough; a psychological breakthrough, such that we come to a completely new understanding of what the universe is.
Until then, we'll have to be content with looking through our telescopes. Twenty thousand years is a long timeline for a mission, even a robotic one.
P.S. - It's late, so my math might be wrong, but according to your numbers, that trip would be more like 690,000 years, or 36,000 with the VASMIR.
There is another, most likely much easier in fact, way to circumvent the light-speed barrier problem for creating an interstellar society. Instead of FTL space travel, which may or may not be possible, go for life-span extension. A 10 000 year long trip isn't so big a deal if you can expect to live a million years.
We'll probably still need to adjust psychologically to the reality of time dilation near-light speed travel, though.
I guess a similar situation would be if we lived in a universe unrestricted by time. We would live forever and could travel anywhere instantly.
What we should do is build a fleet of space telescopes that have their own propulsion and navigation system, like the ion engines that some spacecraft are now purpoted to be using which can approach half the speed of light. They can exit this solar system in less or half the time than it took the Voyager and Pioneer spacecraft.
We would send them out in all directions and they would be equipped with the technology to detect life, water, possibly even evolved intelligent humanoid life or evidence of civilization, planetary temperatures and seasonal variations as they approached target solar systems. In 20-30 years we could have up close orbital observations of some living planets, and in less time than that depending on the advancement in space telescope technology we could determine wether a solar system is worth the time for investigation and change the probes course to a different system.
You understand, don't you, that with very large space-based (not traveling, I mean based in this solar system, but well away from Earth) you can do all that from right here? Without waiting for them to cross many light years?
It'll be easier to build telescope mirrors hundreds of meters across (or multiple mirrors, many tens of meters across for optical interferometry), to get the resolutions you want, than to build these 'telescopic starships.'
If the Voyager spacecraft were equipped with such telescope technology we would have some astounding results today.
Assuming we could get to a faraway planet, what makes anyone think we can be good stewards for it?
We can't even take care of our own planet.
Frankly, by the time we have the technology (if we ever do) to be able to actually get to these other planets and live on them, we probably won't need to live on planets anymore. (The very same technologies that make such a journey possible also make it possible to simply live in space in spaceship-colonies with environments tailor-made however we want them to be.) I doubt that if we actually manage to get to this point in technological development, we would ever actually be called upon to be stewards of any planet ever again. (Or, to put it another way, we'd be the best stewards possible, because we'll be leaving all the habitable planets alone, only observing them or visiting briefly for recreational purposes).
From what I've heard, once we finally break the speed-of-light barrier, the Vulcans will make contact and help us along.
What about quantum entanglement? The ability to manipulate the state of a particle from any distance instantaneously might allow us to develop an interstellar communications network in the distant future.
This was meant as a reply to someone, no idea why it stuck it at the end.
IMO we will never colonize planets outside our own star system. Not because it's not possible but because it's easier to just build habitats in space. Why bother taming a chaotic world when you have a completely controlled environment to live in?
Within the next 100 yrs or so we will be capable of mining asteroids and moons for building materials and manufacturing space habitats of pretty much any size. Most of this work will likely be done by semi-intelligent or intelligent robots.
Once we are capable of building self-sustaining space habitats there is nothing to keep us in the solar system. City or planet sized habitats will be able to explore the galaxy at will with trips between the stars taking multiple generations.
We're sending Republicans into space?
We might still journey to those planets, though, even if not to colonize them. If you have a self-sustaining space habitat with a closed environment, you can go anywhere you want to sticking an engine on the thing and turning it into a generation space ship. One can easily imagine the inhabitants of one or more of these space habitats in the future solar system, for various social or political reasons, deciding the blow off the rest of humanity and head off to another star system on their own, with a view to having their great-great grandchildren be the ones to actually experience arrival.
I would love to be part of an exploratory group sent to another planet to start over. Leave the religious whack-o's behind, after all, after the Great Flood their God said he would not allow the earth to be destroyed again, so they have nothing to worry about by staying here.
Religious wackos will never be left behind. The need for religious belief is hardwired into some humans.
Jim-356239,
Your sarcasm is appreciated, but after the flood, God said he wouldn't again destroy the world with a flood. I'm betting on fire the next time around.
I'd say it's a 50:50 proposition that some sort of fervent religious belief will be what actually motivates the first exploratory group sent to another planet to start over, maybe even a full-blown private cult, fleeing what they perceive to be religious persecution in the old world.
I guess I'm a frustrated astronomer wannabe . . . the number of nights I've spent in open spaces outside the city limits just lying on my back in the grassy countryside with a pillow and looking up into the Milky Way -- indeed within the Milky Way. It's the most amazing and thought-provoking sight. Most people who live in cities rarely see it. But as I laid there I began thinking about and picturing our own location in our galaxy -- and then to know there are millions of glaxies -- just boggled my mind every time. I can't possibly see how other life couldn't be out there. We don't even register as a grain of sand in photos I've seen of our Milky Way Galaxy, that had an arrow pointing out where we were located in this massive galaxy. And while looking at that I felt so insignificant -- really put me in my place. I'd just like to know what this whole universe thing is before I die . . . certainly not likely though.
You ever get the feeling that the powers that be know something we don't? Like this planet is going to explode and they looking to move?
At the current top speed at which we can send even unmanned probes, it'll still take over 10 000 years to reach a star 36 light years away. As in longer than the current known history of human civilization. Notwithstanding whether it is even possible right now for us to engineer something that will last and continue to function that long, or how confident we currently are that our present civilization will be able to last another 100 years, let alone 10 000 years, that's truly "for the future", and in VERY long term....
@Alan Boyle,
This is fun to think about, but misleading overall. The more I think, the more I see a sham and major shortcomings in what passes for applied science these days. Consider the HARPS-Upgrade GTO planet search for example. Now we have (at least) two "prime prospects for habitability" in Gliese 581d and HD 85512 b...but what does that imply? When we think a bit more, more than meets the eye.
In the first place, the notion that some future colonial effort might be directed to a marginal planet with 1.5 times the gravity of Earth is highly unlikely. Why? Broadly speaking, we can anticipate the technical dimensions of a 20 or 36 light year colonial excursion and see without a doubt that we will not have that capability anytime soon: not in a decade, probably not in a generation, possibly not in a century, maybe never. Much depends on the sensibility and cost of a far distant colonial excursion.
Therefore, as we foresee no excursion anytime soon, and take into account the likelyhood of larger telescopes and more planetary discoveries, we should expect many future discoveries more suitable to homo Sapiens than HD 85512 b, for example. By the time we might be "ready to go" in terms of techical capability, we should a fair number of fairly hospitible targets for choosing. In that sense, serious consideration of Gliese 581d and HD 85512 b at this point in time is shortsighted nonsense.
But wait, there's more.
Before giving serious consideration to some future long-range colonial excursion, we should spare a thought to distinguish a 36 light year excursion from the ocean transit of Christopher Columbus. Intercontinental colonialism was feasible in the 16th Century in terms of sailing ships, trip times and distances, and, critically important, the economic / political value of what could be transported back and forth. It is pretty clear in view if the vast distances involved in interstellar colonization, that any material substance transported back and forth should have astronomical value (literally)...or why bother? I tried but could not imagine any such substance. That is not to say it doesn't exist, but we are not likely to discover it in advance with large telescopes
Therefore, at this point in time, there can be only one justification for light year colonial excursions, namely, to propagate homo Sapiens, and who knows, perhaps other Earthly species, as well, to far distant places. There will be no intersteller trade of precious stones, exotic animals or psychotropic spice. Physical excursions would almost certainly be one-way trips, away from Earth with no returns. That raises a question of paramount importance: what is the sense of spreading human seed to far distant places? Is that question too far-fetched for public consumption? I don't know. Certainly though, it is basic to what we are doing now and thinking of doing in space. In that sense, going to the Moon was a political stunt. Nobody would want to die on the Moon, but nobody would want to live there either (but briefly). Same for Mars. Venus more so.
So let us make sense of these things, and if they do not pass logical muster, let us put them aside. I would certainly say (something like) that if I were you.
Ok..so what. So what if we get a signal..OK FOLKS WE ARE NOT ALONE...we can't do anything about that other than realize that this place has a long way to go and that those signals represent a long dead or evolved planet that we can't know..all we know is what we have.
Well, clearly traveling to such a planet is presently out of the question. Observation is the prudent course of action needed here which we are certainly more capable of and better equipped for. The time required to travel to such a planet is something we are simply not prepared to deal with. (We are still having trouble just getting to Mars).
As an aspiring Astrobiologist, the idea of a habitable planet is very tantalizing. However, I think a series of better questions here is, what if life, in a similar state of evolution as ours, is already there? What if we were capable of getting there but hadn't previously made some kind of contact with them prior to making such a trip? Would they blow us out of their sky? What would we do if the circumstances were reversed? I am all for space exploration but we are still, technologically, in the "baby steps" phase of traveling within our own solar system.
There will come a day when we need to get off this planet to continue our species because our moon is too far away to keep Earth on its axis or our Sun has spent all of its fuel and begins to swell and cook all the inner planets, but that day is is millions/billions of years in the future. In the meantime let's use the time we have here to first figure out a way how to clean up the junk yard floating around in our lower orbit, improve our methods of basic space exploration and communication, and look forward to the day when we are more capable of taking care of each other before trying to make contact with an advanced life form that may or may not perceive us as a possible threat. We've got a long way to go folks.
hmmm...I have not read all the posts yet but first we gotta get a few points straightened out. First and foremost, THAT planet may appear to be 36 or whatever light years away, BUT, that is NOT where it is NOW, nor where it will be in twenty or however many years!!...any questions? none? good. because to figure out anything in terms of time of arrival and total travel time, you need a lot more positional data. SECOND, the speed of gravity IS not equal to the speed of light, it is only ASSUMED as such!!...a lot of people have published a lot of bull crap to justify everything from ligo to extrasolar misions, fine, great, BUT...no one has yet ACTUALLY measured the ABSOLUTE velocity of gravity!!...nada, no-one, NOT ONE...a few claim to of estimated it via inference, and most just stand behind al's formulae, BUT, no gravitons have been detected and no one has actually demonstrated space warping....in fact there are several photos of superluminal ejecta from several cosmic sources, I have personally questioned at least one hubble related dude on the very TITLE of his article, and his answer is that superluminal is only an illusion....we'll ok... so here we are again, corpunicous in lockdown, gallileo shunned and the masses threatened with ridicule if they dare QUESTION what is not proven....and don't quote me a bunch of crap, if the sun magically dissappeared, the light would shine on us for about eight more minutes, BUT, we would immediatly leave the curved tangent of the orbit around sol in preference for a straight line!!..don't believe me, tie a rock to a string and swing it around then let it go....GET FRIGGEN REAL...the first proof came during a radar mapping mission of venus decades ago.....we do not yet know what gravity is...besides, I hate string theory and think it's more manufactured crud, but one thing is for sure, if a particle zipped in front of you faster than the speed of light, what the heck would you see? a bright string whose length is the minumum quanta for that speed in it's equivalent length?...
20 or so years to get an imperial probe droid there ain't so far fetched, I suggest we start soon, and launch deep space communication network nodes once a month in it's foot steps so internet+dog can get the information in roughly 40 years, plausible, look how long it has taken V'GER to get to the land of the big bubbles!!....and on FTL, maybe maybe not, I bet some cave man was gathering every rock he could till he found flint, in the meantime his buds were all like, dude, put that down, you can't make fire, only the god's can do that....Let's get out there and start testing some of these faster engine designs, christ we ain't even at wilber's level yet...yepper, think of the space shuttle as pre KITTY HAWK. Naysayers are killing the country, please go to hell and leave the rest of us alone to progress as we will anyways, and take the damn nanny state with YA!!!
Next point, The keppler mission ain't over yet. and it only coves a small patch in the sky, before debating to go to any exo planet, I think it would be prudent to take a more complete look around. I am sure there is something closer. Let's give it a chance to enumerate a few more canidates. Thanks for the formulae, greatly appreciated, I suggest that kepplers data contains more than we realize (have looked at the raw data)....there may be other effects not yet taken into account when analyzing the photmeteric data, what?...well, I might not wanna just hand that right out for free,even if I had that particular answer.
We've only been capable of electronic communication and distant travel for a very few Earth years. Given the age of the universe, the odds of matching up and finding a similarly advanced alien culture on the same tiny time line segment is astronomical. There may have been intelligent life on a planet somewhere - but it could have died out a million years ago. Or conversely, a similar planet is 100 million years behind US on the Darwin evolutionary path and WE'LL be long gone before the microbes walk out of THEIR primordial slush, start walking and eventually create their own rocket ships, etc.... The odds are overwhelmingly stacked against us meeting an alien culture or inhabiting another planet.
So let's summarize this: IF we somehow find another habitable planet, and IF we somehow devise a propulsion system that will enable us to travel near the speed of light, and IF we somehow manage to find someway to travel at this speed and yet maintain our identity as physical beings, and IF we somehow manage not to plunge our present (and at this point) only planet into darkness and ecological disaster and financial ruin BEFORE we accomplish those things, and IF we somehow find a way not to totally wipe out all life on earth -- IF we manage to somehow accomplish all of these ifs and we do in fact reach another habitable planet and colonize it, guess what -- there WE are -- humans in all their glory, who could not take care of the planet they were given, who polluted and degraded the most beautiful planet known that IS habitable and totally our own, then just what do you think WE are going to do on this new planet, other than to totally degrade and destroy it just as we doing to earth, because WE cannot leave our nature behind. Remember, no matter how far you travel, when YOU get there, there YOU are. You cannot escape yourself by moving to a distant land, and humans cannot escape their inherent flaws by traveling into space. What, do you all think traveling to another planet will be some panacea, and WE will be magically cured of our humanness, and actually live on this new planet in peace and harmony and take care of it in a responsible manner? Please, why don't we just spend the money and use our energies to SAVING THIS PLANET instead of some pipedream fantasy of saving ourselves by moving to another world.....
Traveling light speed or 186,000 miles/sec would take 20 years from our perspective on earth right? But if we had the capability of using dark matter to create a portal, aka wormhole to this new planet, the astronaut wouldn't have to travel half the speed of light to get there in no time flat right? But when he got back, we'd be 40 years older??? Boggles the mind!!!
Just because we are finding other planets that we could possibly live on, don't you think it would be wise to learn how to take care of this one first. Earth is not like an old pair of socks. You can just throw her out, because we just wore her out! Also, do you really think we would be allowed to live and trash another planet with the way we treat this one. Mother Earth might have something to say about this first.
what makes gravity greater on super earth?
Size as the same reason the moon and mars has less gravity than earth