SETI Signal

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  • #26
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The Bob said:
The Bob (2004 ©)
Bob, why putting this notice? Do you think your quotes are exclusive or never done? :rolleyes:
I suggest you use it when you have something important to say.
 
  • #27
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"Bob, why putting this notice? Do you think your quotes are exclusive or never done?
I suggest you use it when you have something important to say."

its just his sig, why so harsh?
 
  • #28
Evo
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pelastration said:
Bob, why putting this notice? Do you think your quotes are exclusive or never done? :rolleyes:
I suggest you use it when you have something important to say.
I like his sig. :approve:
 
  • #29
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Evo said:
I like his sig. :approve:
That's the point. It a general sign, not his sign.
It's like an official statement that nobody may copy a specific text. The sign indentifies the author.

But it's not forbidden of course. Bob can use it.
Indeed Bob has copyrights on 'his' text whatever the content and his way to put it.
But say that he quotes from a newspaper and he puts "his sign" under the post he could have trouble since juridically he claims to be the author of the text.
 
  • #30
Nereid
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Should we also avoid reading anything written by Newton or Darwin? After all, they were clearly influenced by all kinds of strange and wonderful religious-based ideas :wink:

"Rare Earth", IMHO, is well worth reading; if you don't want to buy a copy, then check it out from your local library. Perhaps I could start a thread, specifically to discuss the approach Ward and Browlee use, the assumptions, etc!

I'll see if there's a copy of Darling's book in my local library, sounds like it could also be a good read.

The article to which Evo gives a link says: "Darling begins with a point-by-point scientific critique of the Rare Earth hypothesis. The hypothesis essentially says that for life to evolve and survive beyond the microbial stage a very special combination of factors must prevail (such as presence of a large moon to stabilize the planet's orbit, a Jupiter-size planet to sweep up killer asteroids, the occurrence of plate tectonics, and a sun with high "metallicity") and that these other factors are both rare in themselves and absolutely indispensable to complex life. Darling examines each in turn and concludes that the hypothesis is based on circular reasoning and that the proponents have fallen into the trap of going out of their way to find reasons why Earth is special." Well, I'll reserve judgement on how good a summary of Darling's thesis this is, but as a summary of Ward and Brownlee's, it stinks. For a start, like all good scientists, the Rare Earth authors are at pains to point out the tentative and provisional nature of all their conclusions, so "absolutely indispensable" is hardly accurate.

Next, 'circular reasoning'. Trouble with SETI, and much of astrobiology, is that we have a sample of but 1, so it must surely be nigh on impossible to avoid 'circular reasoning', no matter what thesis is being proposed.

Further, with just this sample of 1, you could always show that personal hopes intrude into one's thesis; they will in Darling's work, and they clearly did in Sagan's (just read the http://www.planetary.org/html/UPDATES/seti/Contact/debate/default.html [Broken] for a flavour of how one's professional background colours one's views of SETI).

Finally, shortcomings in Ward and Brownlee's work: lots of little ones, and some bigger ones. Perhaps the most glaring - and also the most difficult to overcome, given our sample of 1 - is that they look too narrowly at 'complex life', finding the conditions for it to arise, on a planet just like Earth, rare. But if they'd gone the other way - speculated about how complex life could arise in entirely imaginary planetary systems, for example - they'd have been strongly criticised for unwarranted speculation (and rightly so too; hard observational data on other 'solar systems' isn't sufficient to build any kind of decent case on)

One thing puzzles me though; the SCICOP review says that the Rare Earth hypothesis has been "... embraced by the religious right as vindication of their belief in the special nature of the Earth." Isn't the Earth 'special' no matter what? After all, it's our home. And how does complex life on Earth being rare (if it turns out to be) be of comfort to 'the religious right'? Seems like desperate clutching at straws to me.
 
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  • #31
xild
Orion1 said:
No one knows for sure what caused this signal. There is a slight possibility that it just might originate from an extraterrestrial intelligence. The bright colors on the blue background indicate that an anomalous signal was received here on Earth by a radio telescope involved in a Search for Extraterrestrial Intelligence (SETI)

Reference:
http://antwrp.gsfc.nasa.gov/apod/ap020728.html
http://antwrp.gsfc.nasa.gov/apod/image/0207/unknownseti_cavan.jpg

You may want to call Art Bell on this, on Coast to Coast AM, next weekend, or write him. He said last night that no signals have been received by Seti, and eventually, they may have to close if they continue to get nothing. :confused:
 
  • #33
Nereid
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Arctic Fox said:
And I don’t understand why everyone seems to think that ET life has to be more advanced than us. What ever happened to being equal? :) There could also be the possibility that ET doesn’t have any fossil fuels on their planet - thinking that typical generative devices like engines to rockets would never have been thought of. Instead, everything would have been designed on the electrical. So, they (ET) may all have cars that run on hydrogen or electricity, and their scientists have figured out different ways to fly using “electroGravitics” ;) and have figured out better ways to send signals through space. At the same time, their children are still making mudpies, regular jobs are hard to find, cable tv shows are horrible just like here, and they still can get sick and die.

We may be equals, but just thinking differently.
The main reason is time ... homo sap.'s understanding of the physics (and hence technologies) that we use to do our SETI is extraordinarily young; Newton couldn't have built a radio telescope, let alone Archimedes ... and that time period is <10,000 years, which is but ~0.005% of the time since complex life appeared on Earth. What if "ET" communicates using some subtle properties of neutrinos or dark matter? We poor homo saps know very little about neutrinos and are essentially clueless about DM! (But look how far we've come ... in <100 years!!!)
 
  • #34
Nereid
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Nereid said:
Should we also avoid reading anything written by Newton or Darwin? After all, they were clearly influenced by all kinds of strange and wonderful religious-based ideas :wink:

"Rare Earth", IMHO, is well worth reading; if you don't want to buy a copy, then check it out from your local library. Perhaps I could start a thread, specifically to discuss the approach Ward and Browlee use, the assumptions, etc!

I'll see if there's a copy of Darling's book in my local library, sounds like it could also be a good read.
Found it, read it. It's a review of the current state of astrobiology, written by a science writer. In this it differs considerably from "Rare Earth"; it isn't out to make one case or another.
The article to which Evo gives a link says: "Darling begins with a point-by-point scientific critique of the Rare Earth hypothesis. The hypothesis essentially says that for life to evolve and survive beyond the microbial stage a very special combination of factors must prevail (such as presence of a large moon to stabilize the planet's orbit, a Jupiter-size planet to sweep up killer asteroids, the occurrence of plate tectonics, and a sun with high "metallicity") and that these other factors are both rare in themselves and absolutely indispensable to complex life. Darling examines each in turn and concludes that the hypothesis is based on circular reasoning and that the proponents have fallen into the trap of going out of their way to find reasons why Earth is special." Well, I'll reserve judgement on how good a summary of Darling's thesis this is, but as a summary of Ward and Brownlee's, it stinks. For a start, like all good scientists, the Rare Earth authors are at pains to point out the tentative and provisional nature of all their conclusions, so "absolutely indispensable" is hardly accurate.
Well, the SCICOP review of Darling stinks too. :grumpy:

Darling's book devotes only one chapter (out of 9) to the Rare Earth ideas, their authors, the influence of the creationist, politics and US funding for astrobiology (etc). In fact, Darling is quite careful to give the ideas in Rare Earth - and the authors - credit for quite a lot. Darling is also careful - though perhaps not so fastidious as Ward and Brownlee - the emphasise the tentative nature of all astrobiological results, and states clearly that there are no compelling observations (etc) which rule out the Rare Earth idea.

Darling's examination of the weaknesses of the Rare Earth idea is somewhat selective - he looks at 'A Large, Nearby Moon', 'Catastrophic Impacts', 'Extrasolar Planets', Jupiter's Protection', 'Metalicity', and 'The Galactic Habitable Zone'; he doesn't look at plate tectonics. As Darling's intention is a review, he is able to take each of these 6 points and present some counters; fair enough. What's lost, perhaps, is the range of views on each item, and the extent to which they're inter-related - i.e. a single, coherent 'Common Earth' case.

Further, some of Darling's own counters to the 6 Rare Earth items are weak, and one has already been overturned - there is now considerable evidence that planetary systems are rare in low metallicity environments (at least, systems with Jovian-sized planets).
Next, 'circular reasoning'. Trouble with SETI, and much of astrobiology, is that we have a sample of but 1, so it must surely be nigh on impossible to avoid 'circular reasoning', no matter what thesis is being proposed.
It seems that the 'circular reasoning' critique is of the SCICOP reviewer's making; Darling spends some time - as does everyone serious in this field - talking about the limitations of a single sample.
 
  • #35
canopus
How many areas does seti scan ( i maynot express myself clearly) ? Could you give me an exact number?
 
  • #36
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http://setiathome.berkeley.edu/images/skymap_wugenerated.gif [Broken] This shows the current sky coverage totals of SETI. Hope this helps.
 
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  • #37
canopus
Hmm, maybe i couldn't notice but i couldn't find the percent that seti scans. However i remember it as 1%, is it right?
 
  • #38
Nereid
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Approx 30% of the sky can be 'seen' by the Arecibo telescope, that from 2o to 35o. However, the beam of the receiver is quite narrow (the new equipment will make a big difference), so you can see on the gif image which check posted that not all the sky between the limits has been observed. In any case, the program requires that all parts of the sky be observed at least twice.
 
  • #39
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Canopus, do you mean in total or in one scanning session?
According to the SETI site, it's scanned over 95% of the visible sky since it began. About 68.4% of the data it has collect has been checked. http://setiathome.berkeley.edu/process_page/ [Broken]
 
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  • #40
canopus
I mean 1 scanning, and it surprised me (: big numbers.....
 
  • #41
Nereid
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check said:
Canopus, do you mean in total or in one scanning session?
According to the SETI site, it's scanned over 95% of the visible sky since it began. About 68.4% of the data it has collect has been checked. http://setiathome.berkeley.edu/process_page/ [Broken]
'visible sky' here refers to that visible with the 'scope, not what someone at the Equator could see :wink:
 
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  • #42
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http://setiathome.berkeley.edu/images/skymap_sp_493.gif [Broken] thats what a typical session looks like
 
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  • #43
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Nereid, thats probably why it says 'visible sky' and not just 'sky'.
 
  • #44
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Sorry for being so late to reply to anyone. I forgot I posted in this section. :frown:

DarkAnt said:
its just his sig, why so harsh?

I think it was a simple misunderstanding. :smile:

Evo said:
I like his sig. :approve:

Thanks. :biggrin:

pelastration said:
That's the point. It a general sign, not his sign.
It's like an official statement that nobody may copy a specific text. The sign indentifies the author.

But it's not forbidden of course. Bob can use it.
Indeed Bob has copyrights on 'his' text whatever the content and his way to put it.
But say that he quotes from a newspaper and he puts "his sign" under the post he could have trouble since juridically he claims to be the author of the text.

The copyright is not on the text but on my name and it is more of a joke than a serious thing. Most people have an avatar or a quote under each of their posts, I have a simple copyright sign. Very sorry you saw it the wrong way. I created my nickname and I use it and I thought it would be funny to have a copyright sign next to it. That was all. :smile:

The Bob (2004 ©)

P.S. Oh course anyone can use the name and I was asked in another thread on what was copyrighted etc..... Sorry again.
 
  • #45
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In reference to the question of radiowaves being detected from space, I would agree that a alien race that would be more advanced that ours would not use radio waves at all. as they travel slower than other particles known to man. It would make sense to use a form of light source such as a lazer to project information much as fiber optics are used in comunication. Or something similar. If civilzations are more advanced even by 1000 years and had the means to industrialize and push their science who knows what they could acheive. If man can only use a small portion of his brain would you not push science to increase the capacity to learn and absorb and explore? it would seem that even if we were to be contaced could we even comprehend a single sentence from one of these beings. something to think about, maybe were looking in the wrong spectrum.
 
  • #46
Nereid
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check said:
Nereid, thats probably why it says 'visible sky' and not just 'sky'.
I guess. It's important for readers to understand that the sky 'visible' from the Arecibo site (with your eyes, for example) is considerably greater than that 'visible' from the radio telescope itself. :smile:

The telescope is simply a bowl of 'chicken wire' (not; it's actually steel panels) in a limestone sinkhole, with secondary and tertiary reflectors placed near the focus. The telescope points in only one direction. It thus relies on the Earth's daily rotation to 'see' different parts of the sky, to 'move' east and west. To 'see' north and south of zenith, the secondary and tertiary reflectors (and receivers!) move along the azimuth arm. http://www.naic.edu/about/ao/telefact.htm [Broken]
 
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  • #47
Evo
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Could space signal be alien contact?

Thu Sep 2, 7:09 AM ET


LONDON (Reuters) - An unexplained radio signal from deep space could -- just might be -- contact from an alien civilisation, New Scientist magazine has reported.

The signal, coming from a point between the Pisces and Aries constellations, has been picked up three times by a telescope in Puerto Rico.

continued

http://story.news.yahoo.com/news?tmpl=story&cid=857&ncid=757&e=10&u=/nm/20040902/od_uk_nm/oukoe_space_signals [Broken]
 
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  • #49
Evo
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As I figured. :frown:
 
  • #50
Ivan Seeking
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Fear not. The odds are in your favor.

I don't know what that means but I saw it on a fortune cookie and I thought it applied. Funny enough, here is another one. Hmmm. It says "Help! I'm being held captive in a Chinese fortune cookie factory". Well, maybe that one doesn't apply. :biggrin:
 

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