Extrasolar Planet Could Harbor Life 308
BlueMorpho writes with a link to a Space.com article about a recently discovered extrasolar planet that may be able to harbor 'life as we know it.' Orbiting around the star Gliese 581 is a small rocky ball that might have the same liquid ocean and drifting continent configuration we're familiar with. The find may be unique in all of space exploration as this planet appears to be within a habitable band of temperatures for life, and is categorically not a gas giant. "The bottom line is exciting ...The conditions for life could be there, but is life itself? As yet, there's no way to know unless the planet has spawned beings that are at least as clever as we are. As part of the SETI Institute's Project Phoenix, we twice aimed large antennas in the direction of Gliese 581, hoping to pick up a signal that would bespeak technology ... Neither search turned up a signal."
Needless hype: good publicity or bad conditioning? (Score:5, Interesting)
When the media flogs "science" stories like this, full of marginal ideas that probably aren't true are we just conditioning the public to ignore actual science as pie in the sky crap? Or does the break from Paris Hilton news stories have some tangible benefit to educating society at large?
Re:Space/Genetic Exploration (Score:5, Interesting)
The medical science and technology might the easy part compared to interstellar travel though.
Might be hell to live on... (Score:5, Interesting)
A "year" where the planet rotates around the star is only 13 days. If tidally locked, a "day" is the same amount of time.
The same tidal forces would also make any large oceans on the surface prone to immense tides. The strong tides may also result in more tectonic activity than on Earth.
Re:Needless hype: good publicity or bad conditioni (Score:5, Interesting)
kill the aliens (Score:1, Interesting)
some people get ecstatic about little green men. me, i could care less about aliens, i really couldn't. fuck aliens. i just want somewhere else for humans to live so us, the human species, survives. that's job #1 for me
i'd be willing to exterminate the little green suckers too without a second thought if they interfered with our colonization efforts. i'm not in any way joking. people love aliens. i could care fucking less about them
in the next few centuries, before we colonize gliese 581c, if we get hit by an asteroid or a supervolcano, or someone like osama bin laden gets his hands on nanotech or enough nukes or a superbug or a certain chemical, civilization is doomed, perhaps permanently
and perhaps our species, our very existence, ends
what does that mean to you?
this new earth-like planet could be our insurance policy, our lifeboat: one planet can get wiped out, and mankind will still survive on the other
in my mind, weighing that insurance policy against little green men?
it's not even an afterthought: kill the little green men, wipe them out, colonize. i'm not joking in the least. that they go extinct so that we survive? sorry suckers, your extinct
now the THIRD orb we find that is colonizable?: if it harbors extraterrestrial life, well then, that's another story because our insurance policy is already reached. colonization can be forestalled or modified for coexistence
my story on Gliese 581c on kuro5hin [kuro5hin.org]
Re:So... (Score:2, Interesting)
At 10.8 miles/s -- the current speed of Voyager 1, 373,000 years (I rounded -- alot).
If we can jack that up to .25c (a considerable feat), it falls to 80 years, but the crew will only age 79 years or so.
Now, if we double that to .5c (a damn-near impossible feat), it becomes 40 years, with the crew only age 36 years, provided they don't become goo from the massive g force they will feel getting up to .5c.
Re:The trouble is (Score:3, Interesting)
Doesn't SETI focus on a specific band of the EM spectrum that is not polluted by solar radiation and thus an obvious place for any sentient beings on another world to broadcast a signal that would allow themselves to be found?
The follow up question being: Are we broadcasting such a signal at that frequency?
Seems like if we're assuming whatever sentient beings out there think like us and thus we can deduce what they would do to be found, that only makes sense if it's something we would do in order to be found by other sentient life forms.
Atmospheric layers... (Score:2, Interesting)
PLUS planet tilt.
And distance.
And possibly rotation speed.
I'm not saying that life exists anywhere else...just that the odds are against it. Maybe.
Re:The trouble is (Score:3, Interesting)
Re:The trouble is (Score:4, Interesting)
1. Our sun's positioning in this galaxy is basically perfect. We're between two of the 'arms' of the milky way. Meaning we're nestled safely away from the gravitational chaos of other stars that may want to rip us out of our orbit around the center of our galaxy. So that rules out many places in our galaxy. Not saying there isn't a chance. I'm just saying that theoretically, the planets in there may be screwed some time in the future. Most other galaxy styles don't have a 'safe harbor' like this.
2.Earth itself has so many favorable factors for it that it is astounding. The tilt of our axis makes for an optimal environment for life across our whole planet. I remember reading that many astrologers estimate that just a half a degree either way and we'd have much larger ice caps or a band of uninhabitable desert. Our elliptical, almost circular, orbit keeps us in the most comfortable spot. A million miles either way and we'd be toastier or colder. Life could still exist, but it would be less than 'ideal'.
As I understand it, our ferrous core spinning at slightly different speed creates our Van Alen Belts to protect from solar wind.
We have an asteroid belt that has protected us from undoubtedly billions of asteroids over the millennial of Earths existence.
Our tidal locked moon pulls on the oceans causing the Earth to continue spinning at a proper speed to maintain life.
How' that? When you consider all this, and the probabilities being of this happening elsewhere (or just 'enough')... you can pretty well give up hope. But there isn't any fun in that! I'm all for looking for hospitable planets. This universe is fascinating. What a waste to not explore?!
Catholic church believes in alien life (Score:2, Interesting)
In 2001 a polish nun call Sister Faustina, who had died in 1939 I think, was made a saint (canonized). As far as I know canonization is an infallible statement that the person went to heaven and led a life of exceptional saintliness.
In her diaries (which she was instructed to keep by her superiours) Jesus Christ appears numerous times. At one point he says that the universe is teeming with life, and it would be arrogant of us to think that it is only our planet that had life, or words to that effect.
Now because she is canonized that effectively means that the content of her diaries, while not themselves being proclaimed infallible, are approved of nevertheless.
The diaries also claim that Hitler was not the Anti-Christ, and that the Anti-Christ was already living. I would bet on Stalin.
As a result of this nun and her visions of Christ the Catholic Church instituted the Feast Of the Divine Mercy on the sunday after Easter sunday. Apparently if we don't ask God for His mercy we must eventually glorify His justice instead (ie. eternal punishment). And that message was the purpose of Jesus's appearances. Google for "Saint Faustina" for more info.
Re:The trouble is (Score:3, Interesting)
Actually, a recent study suggests that we are passing sideways through this galaxy.
I'm not sure how relevant this is anyway, but let's move on.
Irrelevant: we don't care what percentage of the planet is an optimal environment for life.
Irrelevant if it's ideal or not if it happens anyway.
But that doesn't make life possible, it only makes it more convenient.
We've been hit by some big mofos though, and there's still life here (albeit different from before.) Also asteroid belts may be very common, we're just now starting to be able to detect "earthlike" planets meaning those within an order of magnitude of earth's size or so, let alone rocks.
Given that we don't know if that is even necessary, since we have a sample size of one solar system and only one planet really well-known, I'm not sure why you bothered with that either.
The problem with all of your assertions is that we have a sample size of one. The only planet we can be absolutely sure about bearing life is Earth. We can be pretty sure about some other bodies in the system, like our moon. But we haven't even done a good survey for life on any other planet in this system! There's definitely the possibility for life on Mars, but we haven't even checked there.
For all we know, there might be some organizing factor (some initial constant, if you prefer) that means that most solar systems contain earthlike planets, and that most earthlike planets harbor life. We simply don't know, because our sample size is 1 planet, 1 moon, and we simply cannot draw any conclusions from that. When we've more completely cataloged a selection of other systems, then we will be able to speculate in an informed manner. Until then, it's just jerking off. If you want to know if there are or aren't aliens, no amount of speculation will help.
Re:Space/Genetic Exploration (Score:3, Interesting)
Bacteria, in contrast, do 80-100% of the work themselves. They can actively invade -- move in a directed manner -- and can physically attach themselves to cells and start doing damage. Helicobacter pylori, for instance (the bacterium that causes many ulcers) is shaped like a screw and physically screws itself into soft tissue, where it begins digesting them. Some bacteria can attack any animal that has an open wound, or others, like Clostridium perfringins, that causes gas gangrene, can do the same with any deep wound, regardless of species. I don't know of anything that can eat both plants and animals, but I wouldn't be surprised to find out about one.
Anyway, all this misses a prime point: you need a digestive system that doesn't digest you. If it digests something entirely different, you're completely safe. An alien life form that doesn't use amino acid polymers for the structure of its digestive system, but can (for some reason) digest them into something it can eat, would dissolve humans, or any animals, like salt on slugs.
Re:Gliese 581 is an M class star this is bad for l (Score:2, Interesting)
Being that the planet is larger than Earth, the hope would be that it has a thicker atmosphere to help shield from magnetic storms. Any life may also be adapted to take cover during flair-ups.
Actually, I saw a computer-generated show on I think Discovery channel about just such a world. They figured a tidally-locked earth-like planet would have a permananent red-spot-like storm on it's star-facing side.
Re:The trouble is (Score:5, Interesting)
The answers are, respectively, yes, and no. Though we have made a heck of a lot of noise at other frequencies, and the earliest of those signals are very roughly about 100 light-years out by now. They would be extremely weak and difficult to detect, though with a large enough space-based antenna system, it is certainly doable if they listen in the right direction. Signals that have gotten about 50 light years out are much more powerful; they've reached fewer stars, of course.
I suspect that our "window" of using RF transmissions through the air will close within another century or so. There are better, more reliable things available to us such as fiber; almost incomprehensibly higher bandwidth by virtue of one fiber being able to lie next to another, not so easy when using RF, better availability, much more difficult to interfere with, more efficient in terms of energy required in use... RF just doesn't make a huge amount of sense for broadcast, and this is becoming more so every day. And I say that with a certain degree of regret, being an extra-class ham radio operator who grew up with the romance - no, really, I'm serious, romance! - of radio signals fading in and out from all over the world.
It is what we'd do - we're not doing it for political reasons, not scientific or technical reasons. It has been proposed over and over that we broadcast; and has been turned down every time. The question is, do we want to invite visitors? It is one thing to be curious to see if you have neighbors, and to learn the answer without disturbing them or letting them know we're here; it is entirely something else to let them know we're here, or to invite them over - as unlikely as that seems given what we know of physics today. Considering that it is unlikely, it would be all the more intimidating if someone from the Sirius system, just to pluck one out of a hat, heard our signal and a day after they heard it there, they showed up here. The question is, what would they show up with if their physics are that good? All they really need is the ability to shove a few large rocks in our direction and they could go home snickering about those silly primates that used to live on Sol 3... that concerns a lot of people. Some earth species are quite aggressive and territorial, and man is one of them. Looking at our own behavior, it doesn't seem too conservative to think that the same might apply to someone else. So the politics are knotty.
Re:The trouble is (Score:5, Interesting)
I think you need to recheck some of your facts.
Our solar system moves in and out of the spiral arms as well as up and down through the galactic plane [cornell.edu]. We go through the galactic plane about every 35 million years, and through the spiral arms about every 100 million years. Some postulate that these timescales coincide with various mass extinctions that occurred.
The axial tilt of the Earth changes all the time. The tilt angle varies between 22 and 25 degrees over a period of about 41000 years. There is also precession of the orbit that happens on a 22000 year timescale. The changing tilt angle changes the severity of the seasons (length of seasons, ice ages, etc.), but it doesn't have anything to say about whether the planet could harbor life.
There isn't anything magical about our molten core and magnetosphere. We usually expect large rocky planets to have them, so we find it unusual if a planet doesn't have a magnetosphere.
I wouldn't say that the asteroid belt has protected us. The asteroid belt is basically a planet that either didn't form, or didn't survive. Its existence is probably one of the biggest threats to our survival on this planet. It is a race to see whether a large asteroid or comet hits our planet and wipes us out. Nobody doubts that it will happen again in the future; we just don't know when it will.
The Moon actually causes a drag on the planet that is slowing down the Earth rotation. I don't recall hearing what an ideal rotation rate for the Earth is to sustain life.
Once one gets their head around how many stars there are in just our own galaxy, many people consider it a given that there is life all around in the galaxy. Even if you take the most pessimistic odds for life to develop, once you multiply that by the number of stars out there it would seem to be very likely. The most famous statement of this is the Drake Equation [activemind.com]. Of course, once you consider the extremely large distances between any two stars it is easy to come to the conclusion that all this life will not come in contact with each other (the intelligent life, that is).
My argument against this reasoning (Score:3, Interesting)
Sure, space aliens from planet X that came to visit us would have to be be way more advanced than us. Sure they could wipe us out in a heartbeat.
But, why would they bother?
Why would a race so far advanced, bother to travel so far just to wipe ot some inconsequential race? There is nothing we would have that they would want. Any resources available on Earth they would be able to harvest from any number of other places closer and more convenient given their technology.
It would be like you traveling from the US to Hong Kong to squash an annoying moth. Sure you *can* do it but why on earth would you ever bother? If you are going on such a trip it is far more likely that you are a scientist going to STUDY the moth than it is that you are going to kill it for no reason.