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Other Solar Systems Could Be More Habitable Than Ours
SternisheFan sends word of new research out of Ohio State University into the possibility of life arising in other star systems:
"Scattered around the Milky Way are stars that resemble our own sun—but a new study is finding that any planets orbiting those stars may very well be hotter and more dynamic than Earth. That's because the interiors of any terrestrial planets in these systems are likely warmer than Earth—up to 25 percent warmer, which would make them more geologically active and more likely to retain enough liquid water to support life, at least in its microbial form. ... 'If it turns out that these planets are warmer than we previously thought, then we can effectively increase the size of the habitable zone around these stars by pushing the habitable zone farther from the host star, and consider more of those planets hospitable to microbial life,' said Unterborn, who presented the results at the American Geophysical Union meeting in San Francisco this week."
It seems to me the 'habitable zone' is a pretty fine line. Regardless of the size of the star or the composition of the planets, there's always going to be a particular distance where things work. Off by a little either way, and forget it. This might affect the distance, but it's doubtful it would affect the width of the habitable zone.
For life in general, maybe. Possibly. But not us. Humans require a very delicate balance of things that while any one of them is quite common, there's not a lot of evidence that all of them together is. Oxygen/nitrogen atmosphere in the right concentrations, and a lot of H2O? Probably not hard to come by. Strong and uniform magnetic field to trap the atmosphere and deflect solar radiation? Hard to observe empirically; It could be very rare by some accounts. Presence of a moon or other astronomical event to keep the planet spinning on a single axis and not two? That's somewhat common, though limited evidence suggests the closer you get to a star, the less moons will be in orbit around each planet, so there is that. Stable rotation of the planet at a speed sufficient to prevent one side or another from burning up? Again -- evidence points to a moon being a good promoter of this, and not that uncommon. But we have no direct observation of how fast (most) of the planets detected so far in the habitable zone rotate.
And lastly, let's not forget: We're rendering our own planet increasing inhospitable to life by the year. It may be that, in the future, we look for the presence of global warming as an indicator of alien life, as we frantically work to either save our planet, or try to find a new one to destroy.
#fuckbeta #iamslashdot #dicemustdie
because a warmer Earth would be more habitable than the one we have now. After all, the internal blood temperature of mammals is in the neighborhood of 100 F or a little less or little more, which is the temperature for which biological processes are optimized. Hurrah for global warming, bring it on!
A sufficiently advanced simulation is indistinguishable from reality.
Barring some tremendous breakthroughs in physics, no one's going anywhere.
Make sure the SS Enterprise is loaded with at least $24 worth of beads and blankets.
December 21, 2012 the date of first contact! Seriously, what will we do when/if this happens? Will it mean a paradigm shift for humanity or the implosion?
Out of the unfathomable amount of planets in the universe, there just has to be a better one somewhere. Trouble is getting there
I can't help to think there is more intelligent life elsewhere. There has to be....
As we just are too stupid to find it yet.
I hope we live to see proof....just so the backwards amongst us eat crow.
What is 50% warmer supposed to be? This makes no sense in physics. Only maybe if you refer to temperatures in kelvin.
Do they have idiot project managers? If not, sounds more habitable to me.
Well... big compared to what? That's the major issue, when you get into talking about the size of the universe, if it ends, what is outside of it, you start to get into murky waters. To make things even worse, we are very limited in our ability to comprehend things. Just as there are an infinite number of points in a line, lines in a plane and planes in a cube, there is an infinite amount of time and 3D space in the smallest possible amount of fifth dimensional space.
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
FTA:
But the core isn’t our only heat source. A comparable contributor is the slow radioactive decay of elements that were here when the Earth formed. Without radioactivity, there wouldn’t be enough heat to drive the plate tectonics that maintains surface oceans on Earth.
I wonder... if we're pulling uranium out of the ground and refining it, are we slowly pulling out the fuel that drives our plate tectonics?
The Spoon
Updated 6/28/2011
Yes, warmer is better.
Far more people die from the effects of cold than of heat.
Humans do well in historic periods of warmth.
When the earth is in a cold spell, people die, starve, and crops fail.
I agree...bring it on. The few degrees that the warming alarmists project (based on sketchy computer models)
would have benefits that off-set some of the alleged harms.
Humans live under conditions with 100 degrees temperature range, and the temperature varies 30-40 degrees in a day.
Organisms evolved in hotter times, and will survive in them again.
No one cares that a planet so far away possibly is more habitable because a telescope looked at a spec in the sky and we guessed. How about we stop guessing about other systems and focus on build a space craft than can take us out into space and actually see these systems up close. Keep an eye on the sky for dangerous stuff but it's time for the next great space race, long distance (FTL would be nice) travel.
The star has a role to play. Too much mass and it will leave main sequence too soon. Too little mass and the habitable zone will be within the zone of tidal lock. Late G to early K stars are optimal. Stars with less than half solar mass are theorized not to swell into red giants, however, the fully convective interiors will cause flaring. Again, the habitable zone will lie within the tidal lock region.
The term "Solar System" is a proper noun, not a generic term. The term the article was looking for is "planetary system."
You're right, I wouldn't steal a car. But if it were possible, I sure as hell would download one!
No, warmer would be bad.
A warmblooded animal, such as mammals with their core temperature of ~37ÂC for mammals and few degrees more for birds, constantly produces heat. That is heat must go somewhere, otherwise it would lead to overheating. So the only choice is to run at a temperature which is above that of the environment. Once those temperatures come too close to each other, all animals reduce their activity more and more to prevent said overheating.
So, a jump in global temperature, i.e. one that is faster than evolution can keep pace with, would pose a serious threat to animals in areas where the gap between their core temperature and the environment is reduced.
We may have 25% less radioactive elements in our planet's interior than some of these other planets, but we have a large moon that is causing a significant amount of tidal friction. That should help close the internal heat gap a bit...and as a bonus it keeps our axis fairly stable.
There are many different types of homes out there. Some just have better floor heating than Earth. I rather like our bright heat lamp in the sky...so do the plants in my yard.
A good discovery nonetheless. I'm excited that life may have more places where it can exist, and perhaps even thrive like it has done here on Earth.
In fact, we already pretty much know that Earth is actually highly unstable.
It is surprising we are still even around. The fact that intelligent life even managed to happen here is surprising in itself.
Our planet was considerably more habitable 100s of millions of years ago.
We know there was far far more life than there is now.
And this isn't in relation to the life that has died since we have been around, just in general.
Earth is just an ice age or three away from becoming another Mars if this rock cools further.
And if we try fuck with it any further with stupid geoengineering projects to keep it cool, WE WILL KILL IT instead.
Yeah, kill is a bit of a stretch, it will take millions of years to die, but it can happen. The cycles happen for a reason. Messing with them is a terrible idea.
It isn't so much the die that is the bad part, it is the in-between, the crazy-ass storms, the flooding, the tornadoes, the freezing, the heat spikes and so on.
Our weather is already unstable as it bloody is in the past decade. Imagine that 10fold as a normal year.
Admittedly humans would most likely be off this crap-rock before such an event would be of any consequence, but still...
This is one of those mind-bogglingly vaguely self-evident articles that you still can't help but try to correct (well, at least I can't.)
For what definition of habitable? For a given hypothetical type of plasma-based or magnetic life, I imagine the sun is a pretty happening place to hang out.
And yet, no matter what definition you use for habitable, what does "more" habitable mean? Surely it either is, or isn't. What are we measuring here?
And yet, no matter what definition you use or how you measure it, the central thesis of the article is so meaningless as to almost certainly be true. After all, unless you just cheat by defining habitability on a scale of 0 - 1.0 where 1.0 is defined as "just like the Earth, right now, because I said so", what are the odds that we live on the one planet in the universe with the highest score in your arbitrary meaningless homo-sapiens-centric measurement system? Statistically indistinuishable from zero.
Why do people write this crap and call it science?
Hotter and more dynamic might be great for evolving bacteria, but it might be problematic for things like civilizations or intelligent life. One of the improbable things about Earth IMO is not that life evolved in the first place, but that the surface remained kinda sorta stable for oh, two billion years - long enough for it to grow incredibly complex. A lot of heat and dynamism might get you life evolving over and over to the multi-celled organism stage - and then getting wiped out.
The bolded part is impossible. The probability of the Earth retaining enough liquid water to support life -- and not just in its microbial form -- is 100% (its known that it does, so there is no probability that it does not.) So its not possible for any terrestrial planets in those systems to be more likely to do that than Earth is.
Yers but there were a lot fewer humans in those hotter times, there was plenty of land to spread out over, what will happen when dryspells cause starvation and famine? War will happen and as soon as a nuclear capable nation will be involved things will go from bad to hell in 0 seconds flat.
Reminds me of a saying:
The Moon is just like the Earth, only deader.
Help! I'm a slashdot refugee.
Mars used to have a hot interior with it's attendant magnetic field, volcanos, thick atmosphere, and surface water. Perfect for life! But, look what that did for Martians!!!
My karma is bad. Don't get too close!!!
This is already historically the warmest period that humans have lived through. For most of our existence the human population north of about 35 degrees latitude was counted in the thousands because it was tundra.
"Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
Isn't almost everywhere more dynamic than Ohio?
But they keep telling us warmer is going to be catastrophic. ;-)
But that's not what Al Gore told me!
Does Al Gore know about this? They don't stop. They're never going to stop. It's what they do.
Yes, that's why every human and every other animal at or near the equator is dead today.
Oh. Wait.
I've fallen off your lawn, and I can't get up.
How many have a moon stabilized system to keep the planet from tumbling?
Bigger star with more energy output means longer more stable habitable zone - nothing too surprising...
Once we're a spacefaring species? Like you have noted, it's a pain to be in space and need gravity, light, high temperatures, food, water, radiation shielding, air, water.....
What we should do is change, as a species, so we can survive without all those things. We probably can't even survive near-relativistic speeds without massive radiation shielding. And it'd take a lot less energy for us to move around if we were very small.
How about people that only need light and raw materials to live, think, and reproduce?
--PM
Sorry, lots of things wrong with that post.
It's physically impossible for an object to spin on two axes - if you try you just get it spinning around some intermediate axis. What a moon does is gravitationally "knead" it's parent planet, causing tides in the atmosphere, oceans, and rock. That causes the planet to heat slightly, and may promote the development of life in other ways (tide pools may have played an important role in the early development of life on Earth).
Also a moon will *slow down* its planet's rotation, not speed it up. That tidal heat dissipates energy until the planet is tide-locked with it's moon - in our case we'd have about 12 days per year. The same effect happens in the other direction as well, which is why only one side of the moon is visible from Earth. The sun has a similar effect, though weaker since the sun is much, much further away. Venus and Mercury likely have such long days because they're considerably closer to the sun and so the tidal forces are much greater - given enough time they'll be fully tide-locked and have permanently light and dark faces.
Finally, finding a new planet for us to move to in order to escape the consequences of our actions is not a realistic option - Mars is a likely a viable terraforming candidate, but it'd likely be far easier to repair the damage to our own planet than make that desolate planet green, not to mention it would likely take at least several, and we probably don't have that kind of time if we don't get our act together. Even if we managed the terraforming, transporting several billion people interplanetary distances would likely be beyond our capacity in a relevant timeframe - we're currently adding hundreds of thousands of new people every day. We might be able to create colonies which would be nice for the rich, powerful, and highly desirable, but the vast majority of the population will have to deal with the consequences.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Do you reckon the grass there is greener?
Yes, that's why every human and every other animal at or near the equator is dead today.
Oh. Wait.
He said they reduce their activity. Ever hear of a siesta? It's one thing for temperatures to hit around 100F during the middle of the day, it's quite another for that to be the night temperature and a significantly higher temperature during the day. There's a reason that so many equatorial mammals are nocturnal or crepuscular -- it's too hot during the day to do anything but sleep in the shade/water.
"From the depths of my skeptical and rationalist soul, I ask the Lord to protect me from California touchie-feeliedom."
Why are we impressed with this?
A typical quasar looks about as bright from 33 light years away as the sun does from earth. A quasar's lifespan is from tens of millions to a few billion years.
That means in galaxies with a quasar, there is a shell 33 light years in radius, and a few light years in thickness, in which essentially every planet in every stellar system (as well as rogue planets and moons) is in the "habitable zone".
That seems way cooler to me than speculation about a few planets being in the habitable zone.
on the other side of the galaxy
Unfortunately, it's not just online trolls; the myth of "runaway greenhouse effects" is strong among global warming activists, including people like Hansen:
http://en.wikipedia.org/wiki/Runaway_greenhouse_effect
The habitable zone is not a fine line; it's a nonexistent line. It is a misnomer that is far too anthropocentric.
First, we don't know enough about life to know that life based on chemistry unlike our chemistry is not possible or prevalent. The habitable zone only applies to carbon-based life-as-we-know it. Life could easily be possible using alternative chemistries that can exist on radically different planetary situations.
Then, even taking that into account even life-as-we-know it can exist beyond the habitable zone. For example, one could dream up or even view examples in our own solar system where earthly life could exist that are not in the habitable zone, namely on the moons of gas giants, which are warmed primarily through forces other than our sun. Even parts of planets could have persistent habitable areas for microbial life outside the habitable zone.
Really, all the habitable zone tells us is an area where we are likely to find planets that are close twins to our own. It tells us about potential human habitability. It truly tells us little about actual alien habitability.
__
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
The comparison wasn't to Earth of the future, but, if it was a comparison to Earth "when the Sun heats up enough to evaporate all the liquid water on Earth", then saying that planets in the systems studied would be "warmer than Earth [...] which would make them [...] more likely to retain enough liquid water to support life" would still be impossible, just for a different reason.
I've fallen off your lawn, and I can't get up.
It already is warm enough for humans to survive well, even here in Finland. There are some places that are too warm for humans even currently. We might get a bit more habitable places from areas that are too cold now, but that comes at a cost of killing the people who live in too warm areas.
The overall number of how many can live on the planet is probably going to increase. The inequality isn't necessarily X+Y > X, it can be X+Y-Z > X. Here X is the current number of people, Y is how many new people can live, Z is how many people are killed. If Y > Z, the overall number grows but that necessarily isn't a good thing at all.
First, it is not a complaint. People who said that technically the sun doesn't have to go around the earth, weren't complaining about astrophysical principles. They were suggesting that perhaps the universe doesn't work in the way we are assuming.
Second, your watermelon analogy doesn't apply because we aren't watermelons. The problem with our habitable zone is it is anthropocentric. If you want to make an analogy it is more like a species of fish, who do a survey of life on their planet and never bother to look on the land for it because the land isn't part of the "habitable zone" (for fish).
Finally, I'm not disagreeing with any of the stuff about the habitable zone as being a good place to look. I'm just saying that with as little as we know about xenobiology the concept of the habitable zone should be taken with a grain of salt.
__
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
I don't disagree. What I said is not at all incompatible with what you said.
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
True. But compare this with:
"Venus is the case of a runaway greenhouse effect. The temperature and pressure of the atmosphere decrease with height, so water vapor rises in the atmosphere and encounters conditions that cause it to condense back into liquid water and fall back to the surface - a region called the "cold trap." On Earth, this is at a height of 9-15 km (5-9 miles) above the surface, but on Venus it lies at an altitude around 50 km (31 miles) due to the planet's closer proximity to the sun.
On Earth, the ozone layer is several kilometers above this, and the ozone prevents ultraviolet light from destroying water in our atmosphere. On Venus, there is no ozone layer, and the atmosphere doesn't become opaque to ultraviolet light until a depth is reached below the cold trap. This allows ultraviolet light to destroy water between this height and the cold trap's.
So, as water rises in Venus' atmosphere and reaches this region, UV light dissociates it into two hydrogen atoms and one oxygen atom. The hydrogen is much lighter than the water molecule was, and so it easily escapes Venus' atmosphere. The water will usually quickly recombine with a carbon or carbon monoxide molecule to form carbon monoxide or carbon dioxide. This is probably one reason why there is so much carbon dioxide in Venus' atmosphere today.
Heavy water, however, which is composed of one oxygen, one hydrogen, and one deuterium (a proton and one neutron), cannot reach the requisite height as easily. If it does, it can still be dissociated just like normal water, but this happens at a much slower rate. Thus, a measurement of how much deuterium compared with how much hydrogen today shows that Venus has much more deuterium in its atmosphere for each hydrogen atom than Earth does. This is the strongest evidence that Venus has lost a massive amount of water in its history."
From http://burro.astr.cwru.edu/stu/advanced/venus.html
It sounds there are at least two ways to have Venus water disappear.