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Earth-Like Planet That Could Sustain Life Found
astroengine writes "An exoplanet, 20 to 50 percent the mass of Earth, has been discovered 20 light-years away and it appears to have all the ingredients conducive to sustaining life. It has enough gravitational clout to hold onto an atmosphere and it orbits well within the 'Goldilocks Zone' of its parent star. However, it would be a very different place to Earth; it is tidally locked to its star, creating one perpetual day on the world. Interestingly, this may also boost the life-giving qualities of the exoplanet, creating stable temperatures in its atmosphere."
This is where I stopped reading:
"Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say that the chances for life on this planet are 100 percent. I have almost no doubt about it," Steven Vogt, professor of astronomy and astrophysics at University of California Santa Cruz, told Discovery News.
Chances are 100%. Almost no doubt.
Star Trek fans will know such a planet as "Class M".
The "M" stood for Majel (Roddenberry nee Barrett) who, in Gene Roddenberry's words, "made his life possible".
As an electrical engineer, I feel I have a fairly firm grasp on how people figure out a lot of these seemingly extremely complex things.
Magic.
When you're afraid to download music illegally in your own home, then the terrorists have won!
20 light years is millimeters of astrophysical distance.
It amazes me we have been observing space so long and yet we only now have detected this planet.
It just goes to show how incredibly likely it is to find planets like Earth everywhere in the galaxy.
Really.. I thought life & evolution and development thrived on change...
a little flooding, many die, some adapt
a little freezing, many die, some adapt.
more-- the 'kickstart' of inorganic->organic chemistry, presumably took some random event, a one in five gazzillion possible combination of elements, random elements- that likely would be less likely the more stable an environment it is..
nice flat temp? ya get algae & molds.... no need to improve right? why?
every day http://en.wikipedia.org/wiki/Special:Random
The summary is incorrect. The exoplanet has "a mass three times larger than Earth's", not 20% to 50%
Ethics aside, wouldn't it be easier to genetically modify humans to live in a wider variety of environments? Seems like it would be a far more reachable goal in the near term than getting to these distant planets.
My math might be a little off, but if we accelerated at g half-way there and decelerated at g for the rest of the way, it would only take a ship about 6.04 years to get there. But thanks to Einstein ruining all our space travel fun with relativity, we of us left on Earth would think the journey took 21.86 years. So there and back would seem like 43.7 years to us.
Just 20 light years away is good news! One thing that always bothers me when I read about E.T. life, is the fact that we get excited when we find water or an Earth-like atmosphere somewhere, thinking there should/might be life there. We should factor in the possibility that life may evolve entirely differently from us, without requiring water or nitrogen/oxygen. In that case though, we can't really know how it will have evolved as we have no reference of evolution other than ours. So let's wait, or just go there as soon as we can as aliens.
Venus and Mars are also rocky "Earthlike" planets orbiting roughly in the habzone ("goldilocks" zone).
I'd like to see truly terrestrial planets as much as (more than, probably) the next guy, but I think the reportage here is a bit hyped. Especially given a ~3x mass, that gives it roughly 1.44x the surface gravity (and higher likelihood of a Venus-like atmosphere).
-- Alastair
Spin up the stargate and dial it!
What are the odds that alien astronomers on that world are having their exact same story posted on Alien Slashdot®!?
Well, since the star's only 20 light years away and the previous post noted that the Aussies are testing "Space Beer", you can sign me up for the trip. Maybe by the time we get back the Toronto Maple Leafs will have won the Stanley Cup.
OK, OK, I'm kidding about the Leafs.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
intriguing is the fact that we are studying the planet as it was 20 years ago, not as it is present day. In roughly 100 years we've managed to screw up this planet to no end. Things could be quite different on gliese 581g at this moment and we would not know it. Assuming we could travel at the speed of light and made it there in 20 years, the inhabitants may have already turned most of the planet to concrete and smog. If it is indeed inhabited.
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Not just any magic, but black magic. RF is the same way, in your field.
Sent from my PDP-11
So is this were those Grey bastards come from? The ones who keep abducting me, and sticking probes up my ass!
I don't know of any observational way to determine it at the distances involved (though there may be one), but if you make certain assumptions about the composition of the planet you can determine the maximum amount of time it takes to become tidally locked (basically, all orbiting bodies become tidally locked eventually, it's just a question of how long), and if that time is less than the time we can estimate the planet to have existed we can conclude that it SHOULD be tidally locked.
See also: http://en.wikipedia.org/wiki/Tidal_locking#Timescale
"Interestingly, this may also boost the life-giving qualities of the exoplanet, creating stable temperatures in its atmosphere."
I don't get why that boosts life-giving qualities.
Having unstable temperatures in our atmosphere doesn't seem to have impeded life.
In fact stable temperatures may be a bad thing.
It takes instability to produce the mixing of organic molecules that result in biomass. Lightning. Tidal flow. Wind.
But there's no indication this new planet lacks those. Except the tidal part. Unless it has a big moon. And water.
I actually work quite closely with 2 of the authors of the paper that reports these results. Any questions? I'll try to respond to posts between now and 2 October.
Well, there's lawyers covered, then.
Cheers,
"What in the name of Fats Waller is that?"
"A four-foot prune."
We're here not just because we're in the Goldilocks zone, but also because we're a double-planet (earth and moon). Lots of gravitational stress to help encourage crustal slip along fault lines, and free water to help with the slippage. A runaway greenhouse effect caused by much higher CO2 concentrations converts the water to H2SO4. Once the water is gone (it's still liquid at depth even at 150C because of the pressure), the plates lock up completely, and you get Venus.
Right on. I would even add that perhaps the moon is fundamental to the creation of life.
There was a time when the moon was much closer to the earth, when tides were hundreds of meters high.
There are theories that life might have been created first when some clay crystals with the right shape got stuck with some complex organic molecules.
Maybe if there were no moon, then no complex organic molecules would have reached the right clays.
According to the accepted theories, the moon may have been created in a freak accident, when a Mars-sized planet hit the earth in the early solar system. The combination of a moon-forming impact with being right in the liquid water zone could be an improbable event.
As an electrical engineer, I feel I have a fairly firm grasp on how people figure out a lot of these seemingly magical things.
A sufficiently advanced technology.
OK, OK, I know...
I'm much more interested in the possibilities of exploring alternate Earths. Somewhere, I'm just SURE I'll find a world where everyone in the U.S. uses the evolved form of the Amiga, with Dvorak keyboards in Esperanto. And the metric system. I'm dying for a McDonalds Royale (hold the cheese and pickles), with a medium Dr. Pepper with pure cane sugar (no ice).
Maybe the alternate world in Fringe will be a good start, only less fascist. I love the dirigibles and the NYC skyline.
The submitter should have included this bad boy (PDF) in his linkage. Expecting to see methodology on a discovery.com website? You'll have an easier time getting Steve Ballmer to cough up the source code for MS Office.
PS: As an EE, you should know the specific type of magic: It's most commonly referred to as FM.
Quo usque tandem abutere, Nimbus, patientia nostra?
My what exciting times we live in. Just think... it has only been around 100 years since we realized the universe is organized into galaxies. Only a few hundred since we realized that the Earth is not the center of the universe. Sometimes it is hard to have faith in the future... but discoveries like this touch that small part of me that hasn't become jaded.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
While a stable climate might be great for sustaining life, it seems that the lack of change may also be the very detrimental from an evolutionary point of view since there is less of a need for adaptation. It makes me wonder what sort of life such a planet could sustain, assuming there is life. Would it be very diverse? Or would it be like a field of genetically engineered corn that could be wiped out with the slightest change in growing conditions?
That formula requires knowing the initial spin rate (or current spin rate if you just want to calculate from now until a body is tidally locked). Although I guess given it's mass there is probably some sort of maximum initial spin rate, and even given that rate the planet might be guaranteed to be tidally locked at this point.
Visualize Whirled Peas
First, TFS is wrong. This planet is 3 to 5 times the mass of the Earth, not 30%.
The article also won't tell you what is speculation and what they've actually seen. The planet was detected through radial velocity measurement of the star. That pretty much means the only thing that has been measured is the planetary mass times the sine of the inclination of its orbit relative to the sun-Gl581 line. Hence the large uncertainty.
When they talk about atmospheres they are speculating. There is no way to tell if this planet has an atmosphere, although the large mass helps the case. There's no way to tell if the planet is covered in an 100 mile deep ocean or if it is entirely dry other than by speculating based upon the composition of the host star. With no eclipses and a small planet to star distance it's going to be a while before we know for sure about either.
When they are talking about tidal locking they are also speculating. While the planet would almost certainly be tidally locked to the star if it were the only planet in the system, it could exist in an orbital resonance with another planet that throws off the tidal locking, or it could have a large moon in close orbit, which would also do the job.
I also haven't looked to see which version of the habitable zone definition they are using. I would suspect the run-away greenhouse to ice-line version.
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That's sound reasoning based on the information in TFA but I'm curious as to how they determined it was tidally locked? - They can't see the surface so was it determined by a "spherical cow" calculation based on the age of the star?
Also even if it is tidally locked to it's star how do we know it doesn't have moon(s) large enough to cause tidal pumping? After all it's the lack of moons that cause a lack of tidal forces on Venus.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
We have only ONE place that we know life flourishes.
Also, the star is a red dwarf. Besides being plentiful fodder for jokes involving the word "smeghead", it also means that the star burns a lot cooler than the one we're currently parked next to. I'm also fairly sure that the folks eyeballing this thing would have taken the whole "it has an atmosphere but doesn't rotate" thing into account as well.
No idea if tidal locking always means no plate tectonics, though. I'd be wondering how life would get along w/o a magnetic field to shield it from UV and hard radiation (though that would depend on the spectrum put out by the star in question...)
Quo usque tandem abutere, Nimbus, patientia nostra?
With that close an orbit it's hard to see how it could not be locked. There could be quite a bit of libration, though.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
there is probably some sort of maximum initial spin rate, and even given that rate the planet might be guaranteed to be tidally locked at this point.
Glad you answered your own question. We have a good idea of what rotation rates are possible when planets form in a disk, probable rotation rates are basically a function of composition and mass (very small objects such as small moons, asteroids, and fragments are more complicated because their rotation rates are going to be affected by frequent impacts, but even then there's a limit to what gravity can hold together)
Basically, the planet in question--Gilese 581g, is very very very old. It orbits a red dwarf star whose lifetime is in the billions of decades--20-30 billion years likely (too lazy to check for an actual figure, but it's much longer than the 10 billion years for our sun). Based on the current age of the system it (and apparently every other planet in that system, from the bottom of the wiki page on tidal locking) should already be locked.
If the planet is tidally locked, there would be permanent shade on the dark side, and on the shady side of any mountains near the terminator line, which would provide UV shielding of a sort.
And even with no tidally induced tectonics, might there not be some thermally induced tectonics, depending on how hot things get on the sunny side? All that heat has gotta go somewhere, possibly leading to magma convection...
Cheers,
"What in the name of Fats Waller is that?"
"A four-foot prune."
It orbits a red dwarf star whose lifetime is in the billions of decades--20-30 billion years likely
The age of the universe is thought to be between 12 and 14 billion years old.
Maybe we should sent an expedition to check for life on the sun at night when it's cooler?
There's also a problem if we do find life on other planets in-system - they may just be contamination from our past (meteor impacts).
20 light years is *about* 1.25 million AU. Voyager is 113 AU from the sun, in under 4 years it will be 125 AU from the sun. If we pretended Voyager 1 was heading the in right direction it would be 1/10000 of the way there. Or if we imagined that the planet was 10 meters away, Voyager has travelled 1mm of the way there. About 350000 AD, it would arrive!
I'm not doubting them, just wonering how it was determined. My only nitpick of your reasonable theory is that it assumes the new planet has no moon. If it does have a moon then it cannot be tidally locked to both it's star and it's moon at the same time.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Wait, you got all that from statement that it is tidally locked?
Why would the crust have to be locked? Volcanism can't occur in the dark? A molten core can't exist without non-locked rotation? Are the measurements to date even capable of determining for certain it is tidally locked over large spans of time (they just recently found the planet).
Why would CO2 recycling be absent? Because you can't imagine the mechanism? (What precisely IS CO2 recycling anyway)?
You make a lot of assertions with very little evidence. Such a planet would still have weather, winds (rather strong and stead ones I suspect), and perhaps oceans, some of which may span the terminator.
Too many assumptions.
Sig Battery depleted. Reverting to safe mode.
tidally locked isn't necessarily a bad thing. It guarantees that there's a "habitable ring" around the planet that is between the hot and cold side's temps, and its unchanging. So in some respects, it's better than earth here where we have to get used to day/night shifts. Look at what say, the desert does from noon to midnight, huge temp swings. It also means it doesn't have seasons since it's rotational axis is perpendicular to its orbital path. (consider the vast differences we get on the majority of the earth due to change in season) So not only do you have a wide variety of temperatures, but they're almost absolutely stable.
And really, once life gets going and has time to start evolving and improving its ability to adapt, the limits of temperature in general matter less and less and life just spreads out to colonize before-unclaimed territory.
I work for the Department of Redundancy Department.
So, if the plates are locked, atmospheric CO2 quickly passes the tipping point and you end up with Venus - except that if it were the Earth (plus the mass of the moon, plus the other ejecta that were blasted away when the moon was created by the impact), instead of 22 atmospheres, we'd be at 45 atmospheres. In other words, instead of Venus being the hottest planet in the solar system, it would be Earth.
Forget oceans - all the water vapor is tied up in an H2SO4 haze.
Dark side? It would be almost as hot. That dense an atmosphere is very efficient at redistributing heat - plus, light bends almost completely around the planet due to the dense atmosphere. The dark side wouldn't be dark anyway - not with rocks so hot they glow.
When it comes to inhabitable planets, there's no place like home.
and there's no life on the sun.
Maybe we should sent an expedition to check for life on the sun
It's been done: http://en.wikipedia.org/wiki/Xeelee_Sequence_species#Photino_birds
Look, I performed some of the first in-depth analysis of the Gliese 876 system. The inner two planets there are tidally-locked- there's no independent rotation. One side is searing hot (and thus barren), and the other side is frozen solid. The fact of the matter is that abiogenesis (as we understand it) requires a dynamic, liquid/gas H2O environment. This guy's shenanigans about "stable zones" existing between the hot and the cold is utter bullshit. Even if life could develop and then evolve to exist in the "stable zones", you have to remember that this isn't a single planet solar system. The gravitational influence of the other planets coupled with a fast orbital period could cause our poor 581g to wobble even under tidal lock; this would cause the "stable zones" on 581g to shift. In other words, there would be no stable zones. Self-replicating molecules as we know them would not even have the chance to chemically bootstrap.
We are stuck if we don't decide that we shouldn't be. If we are stuck, we need to think about what "sustainable" really means, and it means that the planet can comfortably support about 250 million people forever. Or, it can support 10 billion people for 100 years and then there is nothing left.
So, we have maybe 100 years to figure out how to get unstuck. After that, nobody is going to have a long happy life but a lot of people will have short, uncomfortable lives on a barren rock.
We have only ONE place that we know life flourishes.
NO. We have (at the moment) one planet where we know life flourishes. On this one planet though we have an incredible diversity of places where life flourishes. At every extremity where we least expect to find life we have eventually found it. There are a LOT of places and environments where life flourishes and of the places that we know of not all are particularly "suited" to "life".
So here I am, reading on Slashdot about two teams of astronomers with probably over 100 years of education between them, more doctorates than you can shake a sick at, who are publishing a paper in the Astrophysical Journal about this new discovery, and I find this post by tomhudson essentially calling them idiots.
Only on Slashdot.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
I find it hard to believe we have enough data to even begin to estimate these sorts of odds, particularly since this is the first planet we've detected that's even close to Earth-sized.
I'm also not totally convinced by your arguments that this planet would simply be another Venus, since whether the greenhouse effect is detrimental depends entirely upon the intensity of incident radiation, which is dependent on the brightness its local sun and the distance of the planet from that sun. Greenhouse on Mars would be great, greenhouse on Earth not so much.
Higher Logics: where programming meets science.
And anyway, since when does being tide-locked preclude volcanism? Io seems to be rather tectonically active,
Fifty years of Yippie! 1968-2018
My first thought was that if there is intelligent life on this planet, I would imagine that the part of the surface that has the sun directly above it would make a damn fine place to put solar panels. And the rim between the dark and light sides should generate some excellent wind power.
As a tautology expert, I have a fairly firm grasp when grasping things fairly firmly.
Finally had enough. Come see us over at https://soylentnews.org/
It isn't clear that life only happened on Earth once. In particular, there are life communities around thermal vents in the deep ocean that very well may be the result of a completely different spark of life. For the rest of the Earth, once life gets going, it seems to become rather dominant, not leaving much opportunity for a second genesis, though how would we know if it happened?
In chemistry labs, we find that if the right basic elements are collected and put in early-Earth conditions, some of the complex molecules of life are assembled quite naturally. This is encouraging, at least.
But, 60/40 is just a complete guess, you are correct.
1000 years? That's a heck of a long time. It would be much sooner than that or not at all.
1000 years from now? I should hope that by then we'd have invented something that could move a little faster and overtake any such ship. If we're even still around, and if an enclosed human populace can survive that long at all on such a journey (my bet would be 8 or so generations before some virus wipes them out).
Don't forget that, to the 1000-years-in-the-future humans, we are the equivalent of the people just starting to invent gunpowder and paper and our 1000-years-in-the-future comrades have their own Internet, satellites, Mars-missions and quantum physics. We can just about add up, as a populace, and some highly-skilled polymaths are just getting the hang of second order equations and working out that gravity might possibly exist, while the 1000-years-in-the-future guys have atomic weapons, mappings of the human genome, synthetic foods, worldwide speed-of-light communications systems and cryogenics.
Now translate that forward another 1000 years and our puny "Ooh, we just about got two objects out of the solar system in only 40 years of travel" will be vastly overtaken by all sorts. I wouldn't be surprised if any such project was an absolute waste of time. Hell, we have two possibilities - we overtake the Voyager spacecraft ourselves in the next 100 years or so, or we never even get that far ever, at all, and die out. I think a lot of money would be placed on both sides.
But 1000 years? Please. It'd be better to wait 100 and then do it in half that time with the new advances. Human space travel is barely 50 years old itself, don't forget - you're talking about 20 times the amount of time of the entire history of spaceflight.
Similarly, pissing away billions on something that we will literally be flying past in a generation's time, waving sarcastically from the windows as the other ship would still be a generation away from even home, is a ridiculous idea. There is pretty much nothing between solar systems that is worth studying with human contact, much better investment in long-range unmanned probes until we have the technology to get to those places within a lifetime. Even the moon was seen as an easily achievable distance - it was the cost and technical problems that held back everyone from doing it earlier, not the sheer consideration of a vast distance. As with everything, there are diminishing returns and sweet spots and there is a point at which it will come down to one generation, or some other feasible number and *then* it's worth the investment and not before.
There was little point sending Voyager if we thought we would be overtaking it before it got to the outer planets, but that wasn't scientifically plausible even if we'd invested almost everything we had into the idea - the chances of us catching it within 20 years even if we could launch today are pretty damn slim. This, however, is scientifically implausible - because in several generations the chances of THAT ship being the one to get close to even the closest star and see something new is almost zero.
It's like people vowing to walk around the world - it's more than feasibly possible for one person, with only existing technology, to fashion a vehicle on the starting line that will actually overtake them before they manage to do it. Nice exercise, but in terms of achieving distance and getting to a goal, the guy building even a skateboard on the starting line will win.