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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."
One less thing to worry about.
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.
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.
Tidally locked means that even with an atmosphere the dark side will be *very* cold and
most of the water will likely end up frozen on the dark side of the planet.
"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.
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.
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.
Venus is hotter than Earth by so much (even hotter than Mercury!) because of its atmosphere, not because of its distance to the sun. I think that given the right atmosphere and tectonic activity and whatnot, Venus could have actually been a very Earth-like place.
I could just be talking out of my ass, though.
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?
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?
I thought life & evolution and development thrived on change..
Evolutionary change seems to be enhanced by environmental change, yes, but life itself is an entirely separate matter. Life doesn't have to be complex or evolve rapidly in order to simply exist. In 3.5 gigayears, life on Earth has gone from matted plankton to, well, people. In the same period of time, life on this planet might have gone from matted plankton to really matted plankton. But it would still be life.
the 'kickstart' of inorganic->organic chemistry, presumably took some random event, a one in five gazzillion possible combination of elements
Actually, that's pretty much the exact opposite of contemporary thinking; due to the amazingly rapid appearance of life here on Earth, it's now considered that the sort of self-sustaining chemical reactions that lead to what we call life are quite probable. Not a "one in five gazzillion" chance, but a near certitude. Which is why we expect to find evidence of life (probably extinct) on Mars, and (maybe-not-extinct) in the subsurface oceans of Europa.
So, first we have reports about UFOs sightings over nuclear silos, then the UN appointing an Alien Ambassador (promptly denied), and then a nearby life-sustaining planet is announced...
Hmmm.... if they start rerunning ALF on prime time, we're in business!
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.
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.
There is an argument to be made that because of the very physics of the universe that life itself may be not only inevitable but practically guaranteed. This statement is made with consideration of organic chemistry and the pervasiveness with which hydrocarbons not only exist but seem to interact and react to other hydrocarbons. Carl Sagan was the biggest proponent of this hypothesis, that the physical laws of the universe predispose the creation of life. If the hypothesis is correct, that hydrocarbons are so common throughout the universe (which they are) and that their interaction to form amino acids and the basis of life itself is the end result of the laws of the universe (supposition at best) then if a planet is the right temperature, has water and carbon then life should form. (note mars isn't warm enough and has no free water and Venus is way way to warm, but Titan is literally covered in lakes of liquid hydrocarbons)
I agree the guy is a bad scientist for making such a claim, but if you believe this line of reasoning then if you can find a star with planets in the habitable zone, the right size, with water and enough carbon then you will have life "guaranteed". They are just on the cusp of having enough technology to see earth size planets, I think it will be just a mater of time till they can spectrograph the light bouncing off the planet and can find out which ones have oxygen in the atmosphere. Once you find oxygen you know you have life, at least minimal enough life to create free oxygen which can't exist without life because of it's highly reactive nature. I believe Carl was right, that life is an inevitable consequence of the universe, but until we have a better understanding of exosolar planets and that our solar system(and the earth itself with it's super-sized moon and high rotation) isn't unique we don't have the ability to say life is guaranteed anywhere and that's what makes his assertion so silly even if he believes Carl's hypothesis.
It's an interesting area, because you could test the theory. With some massive expenditures of cash it would be possible to stop the run away greenhouse effect on Venus. Once the planet cooled it would rapidly lose much of it's excess atmosphere and attain a condition not that much different than the early earth except for the very slow rotation and lack of a moon. That test would then prove whether the moon (tidal forces) and fast rotation (short nights) were special or essential in the creation of life. If those two variances are important than life could still be quite rare even with the universal predisposition to life from the right physical circumstances. It's been argued that life first started in the tidal pools on earth, without tides you don't get the periodic flooding that life in the current tidal pools needs to survive. Whether life can survive nights that last multiple days or even weeks is another argument that has little to no evidence to support.
Anyway, I don't agree with the scientists affirmation but I do understand why he would believe so strongly that life is guaranteed if the conditions are right.