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Sun's Twin Discovered — the Perfect SETI Target?
astroengine writes "There are 10 billion stars in the Milky Way galaxy that are the same size as our sun. Therefore, it should come as no surprise that astronomers have identified a clone to our sun lying only 200 light-years away. Still, it is fascinating to imagine a yellow dwarf that is exactly the same mass, temperature and chemical composition as our nearest star. In a recent paper reporting on observations of the star — called HP 56948 — astronomer Jorge Melendez of the University of San Paulo, Brazil, calls it 'the best solar twin known to date.' Using HP 56948 as a SETI target seems like a logical step, says Melendez."
First post?
It would be a good target to look for an Exo plant first. Then from spectral measurements see if it has the elements necessary for life (water, oxygen, etc...). Then it makes a good target for SETI to scan.
If there is a lifeform advanced enough to pick up the SETI signals, chances are they've had the technology for thousands of (earth) years. By contrast, just a couple hundred years ago we were reading books by gas lamps and traveling and sending messages by horse and carriage.
Maybe they could organize an expedition to colonize this fertile planet 70 percent covered with liquid water, only 200 LY away? Of course, by that time the original SETI people would be long dead, having gone to their graves happy in the knowledge that they've advanced understanding between alien species...
"Only" 200 light years. Sigh.
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Unless we think a civilization is intentionally sending out beacons to the universe, isn't SETI pointless?
As our communications technology improves, it becomes lowered powered (unlike my old 3W car phone, my curren cell phone only puts out 300mW of signal max) and the leakage from hundreds, or thousands, or millions of point sources of RF signals becomes more and more like "white noise" to someone that doesn't know how to decode it thanks to spread spectrum signals and high bandwidth data encoded in the streams.
The days of 100,000+ watt AM radio transmitters will likely end soon, so there won't be nearly as much leakage to the cosmos.
So there's probably a 100 year window in a civilization's development where its unintentional broadcasts are detectable.
Will we ever intentionally send out a beacon advertising our existence, knowing that it would likely take 100 years or more before any potentially inhabited planet would receive it? And if we do think there's other life out there, do we really trust it enough to tell it where we are?
...if what we were seeing was actually ourselves, just 400 years ago. A wormhole, acting as a mirror...floating at the point they're looking at?
C'mon...you can dream, can't you?
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there's only one star in the whole universe. the universe appears to have more stars because it is has a multi-faceted inside wall -- like an inside-out disco ball -- with each facet being a crazy, warped funhouse-style mirror. this happens to be one of the few mirrors with the least amount of warp. ain't that a bitch?
insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
That's an 800 year round trip for information exchange, I wonder how many other intelligences would be spewing radio waves willy nilly not to mention we haven't even been using radios long enough for that star system to receive anything from us.
"If any question why we died, Tell them because our fathers lied."
"Hey Meepzorp, those creatures orbiting Zfeskew 73875.24543 are trying to communicate with us."
"Man the relativistic bombs."
Python: 'And then suddenly you have a language which says "we're all stuck with whatever the whiniest coder wants".'
Tell us what you find. Until then... who the fuck cares?
Astronomers, people who like astronomy, and people interested in science, just to name a few.
First generation of stars create some heavier elements but still nothing for building life. They go nova and what have you. So after the first generation of stars, we're not at what? 5 Billion years?
Massive stars create elements all the way up to iron in their normal life span and all the heavier elements when they go supernova. They have lifespans measured in tens of millions of years.
It doesn't necessarily take a long time to go through several generations of stars. I thought I'd read recently that we'd found extremely old metal-rich stars indicating that they had in fact gone through several generations rapidly.
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For starters, I do. Some of us like to keep track of endeavors as they happen and not merely be at the receiving end of a "finished product" announcement.
There has been close to 4 billion years of life on Earth. All it would take is another world that started that chain of evolution just a few hundred years earlier, or to have, by chance, evolution form sentient life a few hundred years faster, or one of countless other variable changes, and we are not the first sentient life in the universe. When time lines are that long, you can't just hand-wave and say, "yeah, there was enough time for humans to evolve, but no way could it have happened already"
Yup - the bigger a star is, the faster it burns through its fuel.
spin up the stargate and dial it!
Seriously, there are 10 billions stars essentially equivalent to our Sun, but you have to go 200 light years to find the closest one?
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
The star's ID isn't HP 56948, but HIP 56948 (from the Hipparcos satellite catalog), aka HD 101364, SAO 15590...
Exactly! What was the score from last nights game and what has Britney Britney been up to this week?
I drank what? -- Socrates
Does this mean our sun is a yellow dwarf??
A man spends the first half of his life accumulating stuff, the second trying to get rid of it all.
Twin ? Clone ? Rubbish : similar but unrelated is more like it.
But is tens of millions of years enough to create those heavy elements?
Yes. It is the same fact of being extremely massive that causes them to burn through their hydrogen fuel quickly that allows them to subsequently fuse additional elements up through iron until they undergo a core-collapse supernova.
And were there enough of them early on in the Universe to have created enough heavier elements so that life - especially intelligent life - is relatively common?
Actually the theory is that there were much more massive stars, and more of them, in the early universe, than form today.
Whether that results in sufficient density of heavy elements in some parts of the galaxy to support early development of terrestrial planets, I just don't know.
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If it is the same age as well as chemical composition, both our sun and HIP 56948 may have been born out of the same stellar nursery. This would make it an even more amazing find.
But, unless it has terrestrial planets in the Goldilocks zone, it is unlikely to to be a real prospect for SETI.
I worry that China is broadcasting the source code for Windows Vista, and 200 years from now some alien civilization will receive it and think they're schematics for something great. They'll build it, nearly destroy themselves and then come looking for us.
Technically, yes. That massive gravitational anchor we circle which provides all of our heat and light is a smallish star.
They are probably still driving Pintos
First, a second generation star could have planets that support life.
Second, the stars that form supernovas don't last long, millions of years, not billions. Many generations of heavy stars had time to form and die before our solar system was formed. A system with similar elemental composition or even heavier could have formed billions of years before ours did.
Third, even if it did take ten billion years before conditions were right for the formation of a star system that could support life, that formation happened all over the galaxy. There's nothing peculiar about our sun. It has many thousands of peers in the galaxy, and our planet has many thousands of peers -- sort of earthlike mass planets of similar composition residing in an earthlike irradiation zone around their stars.
There's no reason at all to think we're the first. We just don't know enough to say that. Maybe life is kind of unusual even on planets that can support it. Or maybe every planet that can support it has life after a few million years. Maybe life almost never evolves to complex forms or maybe it almost always does, given a billion years or so.
Think we'll go over there and find a planet just like Earth, but Rome never fell? Or maybe they had an experiment in causing immortality go horribly wrong?
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Why are we wasting time talking, just SETI it! How long could it take to find out if there is a signal??
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I like how they mention that the 23 row by 73 column interpretation is "jumbled garbage". The correct image also looks like jumbled garbage. I especially like the image of a human. How the hell is an alien supposed to figure out what that is without having seen a human before?
The most basic possible message: counting.
Before the human-shaped pixel art, the sequence begins with a simple count, with increasing binary numbers from 1 to 10.
It's a pattern, which is recognizable without any cultural reference, only with some knowledge of math, which is needed to handle the radio signal any way, and this pattern is clearly not a random occurrence. Turn the data the other way around and you don't see any easily recognisable pattern at the begin, so they know it's the wrong way.
If you want to make it clear that a message is a message and not garbage, you try to cram in something that is clearly not random, but that is as simple basic maths as possible :
counting from 0 to some number, list of prime numbers, fibonacci sequence...
Then you could append whatever you want. Life forms at the receiving end might not be able to understand what you mean with your picture, but at least they now they've organised the data correctly because that's the only way where the begining makes some sense in a mathematical way.
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If Hodgkin's Law holds, there'll be nothing for SETI to pick up yet. Adjusted for the travel time, they're just about getting steam engines.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
And recalling that the planet has faced quite a few mass extinctions, wiping out all the "progress" (I use the word guardedly, of course) that evolution had made upto that point, even if another planet started off at exactly the same time as us, its equivalent of the dinosaurs could have become sapient 65 billion years ago...
Gingerbread?
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
I thought at first they discovered Nemesis... that was more exciting for me than the possibility of extraterrestrial life.
Assuming life exists at the target, and it is intelligent enough to understand that it may not be alone in the universe and is actively attempting to answer that question, would it be incorrect to capitulate that perhaps we can expect intelligent life to maintain high power analog communications for exactly that purpose?
vos nescitis quicquam, nec cogitatis quia expedit nobis ut unus moriatur homo pro populo et non tota gens pereat.
Actually the theory is that there were much more massive stars, and more of them, in the early universe, than form today.
Makes sense. All the matter in the current universe was packed into a much smaller space, the initial hydrogen clouds were likely quite dense with minimal angular momentum and would have collapsed into truly stupendous stars.
As I understand it Sol is believed to be a second-generation star that formed about halfway through the time window in which such stars would form, the chemical signature of the initial stellar cloud is the identifying characteristic of such stars (especially the C,O,N and trace heavier elements). That is the essence of the Fermi Paradox - since our star was born halfway through the window there should be no shortage of sunlike stars born billions of years before ours, and with them at least a few civilizations billions of years older than our own.(To put it in proper perspective, their life had plenty of time to reach our current level of development before Sol had even *formed*) If even one of those civilisations spread out among the stars then they, or at least descendants of their bacteria, should be EVERYWHERE, so why don't we see evidence of them?
Personally I favor the efficiency theory - even if they never found anything better than EM radio to communicate with their receivers would rapidly become extremely efficient so transmitters wouldn't need to be as powerful, and to maximize bandwidth their signals would be compressed to the point that they're indistinguishable from random noise, we're well on our way to that point already. Add to that that any long-range transmissions almost certainly would use incredibly tight-beam transmission to maximize range per unit power, and we've got no reason to believe we could detect them unless they came knocking on our door.
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65 billion years is quite unlikely, as the age of the universe is estimated at a little under 14 billion years. 65 million should be about right.
They might feel the urge to squish us the same way we squish a bug. Our existence might offend their sensibilities. Who says extraterrestrial intelligence has to be rational. We're not.