Sun's Twin Discovered — the Perfect SETI Target? 168
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."
Exo Plant first (Score:3, Insightful)
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.
Pointless? (Score:5, Insightful)
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?
Re:Great. So scan it. (Score:5, Insightful)
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.
Re:Pointless? (Score:5, Insightful)
It is really expecting a lot out of an alien to receive this signal in all the space they could be looking at, determine that the modulation of the signal corresponds to binary digits, then determine this number of bits is semi-prime and can be arranged in a grid to pictorially represent the data, make sure they arrange it correctly, decipher what is essentially a cave drawing made by a species that may have close to nothing in common with them, and actually care enough to write back.
Re:I think we're one of the first intelligent life (Score:4, Insightful)
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.
Re:Maybe I'm paranoid (Score:4, Insightful)
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.
Re:Maybe I'm paranoid (Score:5, Insightful)
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! [slashdot.org])
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.)
Re:Yeah (Score:5, Insightful)
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?