Analysis of Spacecraft Data Reveals Most Earth-like Planet To Date 83
sciencehabit writes: Scientists analyzing data from NASA's Kepler satellite have boosted the tally of known or suspected planets beyond our solar system to more than 4000, they reported at a meeting of the American Astronomical Society. Most are inhospitable — too big, too hot, or too cold for any conceivable life form. But another team seeking to verify Kepler candidates announced they had identified eight new potentially habitable planets, including some close to Earth in size and situation. Unpoetically named 5737.01, one candidate has an orbital period of 331 days and is 30% larger than Earth, Mullally says. That’s good news, because scientists here reported yesterday that planets more than 1.6 times the mass of Earth are unlikely to be dense rocky worlds like ours — assumed to be the only plausible habitats for life.
Parameter mismatch (Score:3)
I'm not seeing the good news. If it has a similar density to Earth, it will have a mass about 1.3^3 ~= 2.2 times the mass of Earth.
Re:Parameter mismatch (Score:5, Informative)
Why is that a problem, are you concerned about surface gravity? Assuming a similar density to Earth, it would only be ~1.3 Earth gravities, since F_g falls off with r^2.
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Oops, misread your comment, sorry. Some emphasis on the latter part of the quote would have helped =P
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I ended the quote too early: I should have included the bit
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Planes rely heavily on atmospheric density (no pun intended), so if a world with higher gravity has a correspondingly denser atmosphere, planes would still be possible, though lighter-than-air vehicles (like blimps) would be more practical. Mars for example has lower gravity than earth, but also a MUCH less dense atmosphere, and planes there would need gigantic wing-to-mass ratios to provide enough lift to fly.
Dead-on about the rockets though, and if it's not an iron dense world, there's a good chance it's
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On the other hand, there are two planets in our solar system with less mass than Earth, but denser atmospheres: Venus and Titan. Venus is only slightly smaller and less massive than our planet, but has a much denser atmosphere. Titan is a lot smaller as well as less dense, but has an atmosphere roughly 50% denser than ours -- and full of organic molecules.
Our kind of life couldn't exist on either one of them, of course, mostly for temperature reasons. But we don't have many samples of the conditions i
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Just scooting this in here, Titan is a moon.
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..., Titan is a moon.
Yeah, yeah; but any classification system that puts Mercury and Jupiter into a single class, while putting Earth and Titan into different classes, is just too silly to take seriously. Lots of astronomers take this sort of attitude, and either avoid using such terms at all, or have a bit of fun trolling the people who take them seriously. Some have also pointed out that it makes a lot more sense, scientifically, to consider the Earth's orbit to contain two planets that exchange positions on a monthly cycl
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In any case, none of these heavenly bodies care at all what we call them, and nothing we say can influence their properties or behavior.
Except, it being a moon informs about the potential properties and behavior of the object. A moon has properties that decreases the likelihood of life forming on it.
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Except, it being a moon informs about the potential properties and behavior of the object. A moon has properties that decreases the likelihood of life forming on it.
That's also hard to take seriously. Extrapolating a sample of one to a universe with billions of galaxies, each with billions of stars, is just silly. Not that I'm saying you shouldn't do it, of course. I'd be tempted to answer by arguing that an Earth-size "moon" around a gas giant may be more likely to have life, but of course that would be extrapolating from a sample of zero. (Unless we discover life on one of Jupiter's moons, or on Titan. ;-)
Without a lot more evidence than we have, conjectures ab
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It's not an iron dense world, the magnetic field would be weak wouldn't it? Meaning that things are being inundated with too much solar radiation; preventing life. Or most importantly, human ability to colonize.
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I have a strong suspicion that "size" is being used as a euphemism for mass. I didn't think that Kepler could measure the radius of these planets, only their mass.
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The Kepler spacecraft finds exoplanets by the transit method, looking for drops in light intensity of stars when the planet passes in front of the star. This allows them to measure the radius of the planet relative to the star. So in this case, they usually have the radius, but not the mass, at least without making some assumptions. While sometimes they might have already made those assumptions to make comparisons like this in the news, looking here [upr.edu] suggests that it has a radius that is 30-40% larger tha
Remember folks (Score:2)
It used to be said that Venus was an 'Earth-like' planet
Re:Remember folks (Score:4, Funny)
Is she dense and rocky?
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Problem is that with current knowledge and technology we would NEVER be able to get out of our solar system alive, much less actually make it to the nearest star. We *might* be able to send probes, but we are talking about missions that will have to last multiple decades on internal power supplies and whatever fuel they start with. There is no way that humans would survive the trip on any craft we could hope to construct in our lifetimes.
The exploration of "space" we do will be limited to our solar system
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Who needs to travel? Long distance communication is more than enough to reshape our views of ourselves, our worlds, and to exchange technologies worth untold trillions. Identify enough habitable planets in the sky, monitor and send transmissions, and eventually after trying many thousands you may find a civilization that's listening.
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Try if you want too, but at a 2000 year round trip for a radio signal, you won't be around to monitor for the reply.
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Where did you get 1000 light years from? The actual distance seems to be 1833.4 light years. So a round trip time of 3666.8 years.
And yes that is a long time indeed. Long enough that if you transmitted a message in a natural language you would almost certainly need a very cunning linguist to understand the message you originally sent let alone the reply.
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Problem is that with current knowledge and technology we would NEVER be able to get out of our solar system alive
Orion [wikipedia.org]
I realize that isn't technically current technology, but we could probalby figure out how to use 1950s tech if we wanted to.
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Before we can "invest in technology" we need to have some theoretical basis for said technology to work. Our current understanding of physics provides no plausible mechanism for a living human to travel to these planets. Unless there is a fatal flaw in relativity, it is possible (if not probable) that practical interstellar travel is essentially impossible.
Totally agree, but you are attacking the SyFi culture where it's just expected that Captain Kirk can just order up "warp 8". Einstein pretty much condemned us and our offspring to die with the confines of the Solar System and the chances he was wrong do seem pretty remote so far.
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Before we can "invest in technology" we need to have some theoretical basis for said technology to work.
We do. Nuclear pulse propulsion can get us up to nearly 10% the speed of light. Alpha Centauri in less than 50 years. Within the lifespan of an 18 year old astronaut even. It might take 200 years to actually build the enormous nuclear pulse ship and cost trillions, but we have the tech. We just don't have the money. Or if we do we would rather spend it on something more practical like killing a lot of other humans.
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Before we can "invest in technology" we need to have some theoretical basis for said technology to work. Our current understanding of physics provides no plausible mechanism for a living human to travel to these planets. Unless there is a fatal flaw in relativity, it is possible (if not probable) that practical interstellar travel is essentially impossible.
Well, there is plenty of technology to invest in that would head us down that road that would be useful to our current endeavors. We still need the technology and engineering to build a long term space habitat for things like a manned mission to Mars. Given Apollo level funding, drive, and political will, we are still probably 30 years out from having such. Then there's mining and manufacturing in space to worry about. That will continue past the probably 50 years in getting things up and running in a usefu
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It is perfectly possible to build a generation ship to reach for the stars and colonize planets thousands of years of travel away.
Just not in the way that we think of generation ships...
Cryo-sleep is how science fiction solves this problem, but the only known state of human that can survive cryogenic freezing is the human embryo. a crew of around 6 females, and 40,000 frozen embryos, a new generation of females is implanted via ivf and then born through live birth every 25-30 years.
Lo
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A few 10s of meters of water would block the vast majority of cosmic rays. While there are higher energy ones that would penetrate that, they also penetrate Earth's atmosphere (or create a shower, which actually allows more of it to interact with people on Earth than a single high energy particle would). You could block a lot of that with ~100 m of rock.
Neither of those are anywhere near impossible to construct a spacecraft with, and the need for a generational ship to be self sufficent would give you a m
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Where exactly should such a radiation come from? Oh, the sun? That is easy shielded. Beyond Mars orbit there is not much to fear anymore anyway.
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Cosmic Radiation comes from LOTS of things out there and it's not just the rate of exposure that's the problem here, but the *duration* of the exposure during the trip.
The nearest planet in the "goldilocks zone" is something like 1,000 light years away. The nearest neighbor star something like 10 light years. If we could get something going at say 50% of C, that means we have a 20+ year round trip to the nearest star or a 2,000+ year round trip to the nearest possible habitable planet and back.
The backg
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Outside of our solar system is no serious radiation.
The closest solar system is 4 light years away, not 10.
The closest potential earth like planet is 13 light years away, not 1000.
Letting a potential interstellar craft spin to create artificial 'gravity' is likely a very simple thing.
However I agree that it is unlikely that a human ever sets his feet on a planet outside of our solar system.
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I don't agree that radiation outside the Solar System is low enough to allow us to travel there for extended periods without significant shielding. Even electronics would require hardening and shielding to survive for the time required.
The stories I've been reading today put the nearest habitable planet outside our solar system at 1,100 light years away. Maybe there is something closer, but that's not what I understand these articles are discussing.
Travel at 1/2 the speed of light would be a minor miracle
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The stories I've been reading today put the nearest habitable planet outside our solar system at 1,100 light years away. Maybe there is something closer, but that's not what I understand these articles are discussing.
/. story is about :D ?
So you did not even read the linked article this
http://io9.com/the-closest-kno... [io9.com]
http://en.wikipedia.org/wiki/L... [wikipedia.org]
Radiation always comes from suns, so if you are far enough away you get no radiation except the occasionally gamma burst.
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>The nearest planet in the "goldilocks zone" is something like 1,000 light years away.
Huh? Which planet would that be? What ever happened to Gliese 581c [wikipedia.org]? Did it disappear while I wasn't looking.
The Gliese 581 system is only 20 light years away and could be reachable by a human constructed interstellar ship driven by nuclear pulsed 1950s tech (Orion) in something like 200 - 250 years. A long time, but doable either for a generation ship or for a probe.
Of course I'd set aside another 200-250 years to get t
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Even a generation ship like you describe poses technical problems that may very well be insurmountable.
One issue is small particles in space (micrometeorites). While the space station may have managed to avoid catastrophic impacts over a decade, the probability of a major impact on a ship traveling for centuries at even a very small fraction of the speed of light hitting *something* in space becomes extremely high. At those speeds, a golf ball size object would slice through any known material like a ho
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One issue is small particles in space (micrometeorites). While the space station may have managed to avoid catastrophic impacts over a decade, the probability of a major impact on a ship traveling for centuries at even a very small fraction of the speed of light hitting *something* in space becomes extremely high.
Citation needed. Outside of star systems I think the chances are more like fat and slim.
At those speeds, a golf ball size object
The chances of hitting a golf ball sized meteorite in the vast emptiness of interstellar space is infinitesimal. The point remains however. It just wouldn't be anything nearly that big. It would be a matter of deflecting tiny particles at around 0.1c. Not an easy task, but certainly doable. Perhaps whatever is used for radiation shielding (lead lined water tanks perhaps) would have enough mass to deflect such small parti
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Blame religion. It is perfectly possible to build a generation ship
The people of the generation ship will probably start a new religion before they get there. Or more likely, they'll start several religions and then fight each other over them.
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I'm confused how religion is to blame here? It seems, financial cost, will power, and a host of more basic/physical restrictions prevent this.
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But those things aren't controversial simply from a "religious" perspective. You're implicating a general shift in morality here, religion itself has little to do with that when you consider the universal nature of those morals.
Why not gas giants too? (Score:4, Interesting)
They have all the chemical ingredients, saturn and jupiter both have water clouds containing droplets of water and since we don't know how life actually got going it could well be possible for it to start in a gas giant and at least sustain bacteria or virus sized lifeforms. Even in earths clouds there are bacteria floating about as we've discovered in the last decade or so.
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Preferably human-like life, with sexual reproduction. And compatible female equivalent bits for interfacing. And hopes that the male equivalents don't have bigger dongs than human males.
I've watched Star Trek. I know how to handle inter-species relations.
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My guess is that for life to form you need a place where common elements are brought together by gravity AND importantly, where solid, liquid, and gaseous phases of at least some common elements and molecules can co-exist.
The reason for the latter requirement is that life relies on at least some fairly solid structures to be able to form and persist for considerable time periods. Life needs a vocabulary and grammar of structures: e.g.
- tubes to conduct low-entropy (organized) flows of liquids and gases for
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Since we only have one exemplar to work from, we really can't claim to have any clue what the required parameters are for intelligent life. We don't really know the full requirements for life either, but at least there we have lots of specimens, and know it happens pretty much anywhere liquid water is available. So places that look roughly like Earth and can hold liquid water would be great places to start looking for life.
If there are other bodies we can visit in this solar system that have liquid water,
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Given the exponential difference in volume between a gas giants inhabitable atmosphere and the small inhabitable part of earth on and just below the surface I'd debate whether a rocky planet is the best possible place.
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That's a pointless debate. Prove that life can exist there and maybe the debate is meaningful. Further, there's no sense in spending time exploring a gas giant over an earth like one for intelligent life. You go to the earth like planet and find no intelligent life (or life), oh well. But there's still a chance you could colonize it. The gas giant there's no second place for not finding life.
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Well, in theory, life can be anywhere. The problem is our ability to detect it.
For example, we've done plenty of studies of life on Earth. We take that knowledge and apply it to Mars to see if we can detect any past or present life. We could do the same thing for Jupiter, but we probably wouldn't detect any life because--if it's there--it behaves differently than life that we know. We'll need some other way to detect it, but if we don't know if it exists, how can we come up with ways to detect it?
That's
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-The presidential election will be decided by one vote... on the supreme court.
The margin of victory was more than one vote and the outcome of the election was decided on the day the governor of Florida certified the election results the first time. The appeal to the Supreme court was pointless as it had no power to reverse the decision of the electoral college nor change the vote of the Florida delegates. Gore lost on every front, the initial count (the legal one) AND the following three recounts. The supreme court ruling was just icing on the cake of his defeat. Get over it.
-There will be a nuclear terrorist attack on New York, perpetrated by Israel, the Bush administration, and the Pentagon, with obvious evidence right out in the open, and nobody will question it.
If y
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The post is certainly ironic given the first sentence...I'll give him that.
Not quite (Score:3, Insightful)
Analysis of Spacecraft Data Reveals Second Most Earth-like Planet To Date
FTFY.
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Gas giants usually occur outside the "Goldilocks" zone. So those moons would be ice cold. Ignoring that. You have a object that is not always being hit by the sun, as the moon would be going through the planet's shadow. And then, you have that moons tend to be tidally locked to the planet.
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Quit pointing out cool planets. I wanna GO there!
Like dating the head cheerleader, never going to happen dude..
Physics and Biology pretty much tell us that every human alive and all their offspring will die, here in THIS solar system. No exceptions..
Keep dreaming though..
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You know why they call her the "head" cheerleader, right? Know what I mean? Wink-wink, nudge-nudge.
What's conceivable? (Score:2, Interesting)
Most are inhospitable — too big, too hot, or too cold for any conceivable life form.
Whoever wrote this has obviously never read any science fiction. ;-) The term "conceivable" covers a very wide range of planets (and various environments not based on planets) in which intelligent creatures might evolve.
Some years back, I read Robert Forward's Camelot at 30K novel, about a human expedition to an inhabited Pluto-like planet out in the Oort Cloud; the title references the mean temperature of that world. Part of the story was a quite imaginative method that the world's inhabitants used to
Standard classifications (Score:2)
Meh (Score:2)
None of them are entirely satisfactory: either the climate isn't quite right in the later part of the afternoon, or the day is half an hour too long, or the sea is exactly the wrong shade of pink.