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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.
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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Hopefully they will be advanced enough to know that SETI listens to signals, it does not send anything!
Sometimes the light at the end of the tunnel is the headlight of an oncoming train.
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.
Maybe they could organize an expedition to colonize this fertile planet 70 percent covered with liquid water, only 200 LY away?
If they're advanced enough to do that then they're advanced enough to have detected our planet and its composition long ago. If they wanted to colonize Earth then the plan would have already been put in place and SETI would have nothing to do with it.
So don't worry. It's only a problem if these aliens are for some reason willing to travel 200 light years just to acquire a bunch of slaves. Maybe we should make it clear in our SETI broadcasts that we are very inquisitive creatures, but also lazy and difficult to train?
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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.
The enemies of Democracy are
1) Send a message, "Hello, are you out there?"
2) 200 years later..., "Yes we are, is there something we can help you with?"
3) 200 years later..., "Can you give us the secret to faster than light travel?"
4) 200 years later..., "Obviously not."
Total time: 800 years.
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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"
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...
Close. It's our sun, but in the evil twin universe. Or are we the evil twin? Hard to say, really.
Hoping that we are the Evil Twin. The women are always better in the Evil Twin Universes.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Exactly! What was the score from last nights game and what has Britney Britney been up to this week?
I drank what? -- Socrates
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...
I doubt there are any resources a spacefaring civilization could find on Earth that they couldn't find much closer to home. Asteroids and comets good sources of water and many metals and other elements. Unless they want fresh meat.
Probably the only reasons to travel 200 light years to visit a developing culture are to study it, befriend it, or annihilate it so it doesn't become a threat later when it becomes more advanced.
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.
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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Comparing something incredibly huge to something several orders of magnitude bigger might make the first seem small in comparison, yet it's the mathematical equivalent of a straw man argument: the fact remains that 200ly is an impossible distance, not "practically next door". In fact the first man-made radio signals haven't even reached it yet, assuming they were powerful enough to be detected. And those are travelling at the speed of light, not some miniscule fraction of it.
Seven puppies were harmed during the making of this post.
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.
1. "Hello are you out there?"
2. 200 years later, they receive message, send "Yes we are, how can we help?"
3. We receive first response (400 years total now)
4. We send "Can you teach us FTL travel?"
5. They receive the additional response (600 years total now)
6. They reply "thank you for holding, can you verify your phone number please"
7. We receive their message (totaling 800 years now)
8. We hang up in a panic, realizing our entire planet has been outsourced.
It's great to go back and watch this particular episode of Carl Sagan's Cosmos: Encyclopedia Galactica. He goes through the basic idea of the Drake Equation, opines on listening/detecting life elsewhere in the galaxy. It's really great stuff, and worth watching whether you've seen it before or not.
I only post comments when someone on the internet is wrong.
Why does everyone assume that alien species must be so much more advanced than us, technologically? Your logic is immediately flawed in that WE can pick up the SETI signals and we haven't had the technology for thousands of Earth years, so why must every other species?
That's easy -- because the universe is really old it's vastly more likely that aliens evolved and developed civilization millions of years before we did -- or we are millions of years before them -- than it is that they are in the exact same 100-year window of technological development. The odds are literally astronomical.
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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.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Although passive SETI does not send messages, Active SETI (ASETI) or METI does precisely that. As a planet, we have already sent messages to Gliese 581 and a number of other systems. If I'm successful I will even start sending such targeted messages full time from a 20 meter dish in Argentina. Unfortunately my power levels and antenna size probably limit my messages to a radius of about 50-100 light years, but with very large receiving antennas such messages could travel, much farther, possibly out to 200 ly. My goal is to start a full time. 24/7 targeted beacon. Now that has not been done before, but it's only a matter of time. If I'm not successful in my lifetime surely someone else will be eventually. Even some less cowardly government programs like that of the open minded Ukranians do not shy away from sending messages. They just don't do so as part of a permanent program. I believe that will be left to amateur projects like my own.
Does anyone know the declination and right ascension of this solar twin? I can't find any information on it from googling HP 56948. I'm guessing it probably has another more commonly used name.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
What would be the incentive to organize such an expedition? Even if they are way ahead of us, it will be an enormous enterprise. I'm sure if they are so advanced, they would have to compare it with much better alternatives.
A spot of tea? We'd make great pets? I could think of a million reasons why or why not to visit. Nearly all of the good reasons are non-malicious -- Greed would be a huge limiting factor for the malicious motives... Unless their planet is dying or something.
Think of it this way: Let's say we discovered a TV Signal from an alien race that was less advanced than us? What would we do? Bet your bottom dollar the first (US gov) instinct would be: "Don't tell the public! They'll want to send a message, and that could mean war or our eventual demise." Regardless of the distance, as soon as word gets out to the public, every nerd's mom's sat dish is re-purposed and aimed at the distant planet and beaming them everything from GNU/Linux source code to Otherworldly Erotica. (Heh, here's one now!)
Public support for NASA to launch a small satellite carrying a message of peace would be huge, regardless of the time it would take it to get there, and the near hopeless chance of it reaching anyone... Were we very much more advanced than we are now, it would be a huge scientific find and you can be sure that some of us would be making plans to stop by and say "hi".
(You've obviously never met an Explorer or Mountain Climber.)
But if we're talking about communicating with, observing with a telescope, or sending objects to another solar system, 200ly is about as good as it gets.
So you consider having to wait 20 generations (it's a round trip, remember) to hear the answer to your question, if there is an answer, "communicating with" someone? You believe it's possible to "send an object" 200 light years, when it has taken almost 40 years to send an object around 3 light-HOURS away from earth (Voyager 1 is about 120 AU from us now).
I think there is a problem with the wiring of the human brain; when people see the number "200" somehow this is a familiar number used regularly by people. $200 for groceries. $200 for a hotel. $200 here, and there. The brain obviously skips over the difficult-to-understand light year part and just sticks with good old familiar "200".
I argue that 200 light years is as good to us as 2 million light years. We will never get there. Ever. The rest of your argument consists in believing in magic like project Orion which completely ignores passengers being fried by cosmic radiation at 0.08c even if all the other "minor technical details" could be worked out. And then there is the slight problem of a 2500 year trip when compared to an organism that lives at best 70 or 80-odd years with few exceptions. There are only a few structures humans have ever built that have lasted 2500 years or more, and even then they did not endure unscathed. Entire civilizations have come and gone in that time span. What makes you think a complicated space-craft could be kept running for that amount of time?
Seven puppies were harmed during the making of this post.
"Let's say we discovered a TV Signal from an alien race that was less advanced than us?"
You mean 1000 channels and nothing on?