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View Full Version : Why Don't We Just Blast Out A Message....



DuaneW
2006-Sep-06, 12:42 AM
.... to the few dozen nearest stars to let any "inhabitants" know we're here?

I know we sent out a message in the 1970's to a star cluster many thousands of light years away. Why not do the same for a few of the nearest stars?

Granted, we don't yet have the capability to detect Earth like planets around even the closest stars, but we clearly have the ability (if not the funds???) to send a message similar to the one we sent out 30 years ago to a few of the nearest stars. Nothing ventured, nothing gained, right? Who knows; some of us may even be around to witness a response.

The fact that we haven't leads me to believe it may not be that simple an idea.......

neilzero
2006-Sep-06, 02:14 AM
1 There is lots evidence (most of it rejected by mainstream science for good reasons) that some of the ET are hostile. Why spend big bucks to attract aliens that may reguard humans as a food source or otherwise cause us great grief? 2 The signal will be very costly, especially if we send it out 24/7, and want to make it easy to receive 3 The ET may have no knowledge of English nor German, so devising the message is difficult and ET may think we are hostile (We are hostile) even if our greatest minds devise the message 4 Our greatest minds should be enganged in far more important matters 5 Even if the ET have best of intentions toward us, we may be injured indirectly. 6 Instead I suggest that we reduce our radio ect. energy that escapes our planet and make what we can't avoid escaping, appear as noise. An ET space ship may be passing closer than Earth's moon as we type. Neil

eburacum45
2006-Sep-06, 11:26 AM
Sending a message to the closest stars is not likely to have much success, to be honest. The closest 25 stars are nearly all red dwarfs, although there is one A class star (Sirius_) and one F class star (Procyon); none of these stars resemble the Sun enough to be considered good candidates for inhabitable planets.
The only Sun-like stars among our closest neighbours are the two stars in the Alpha Centauri system; these two stars are actually quite similar to our own star, but are different from our own star in that they orbit each other quite closely. They are separated by an average distance comparable to the distance between the Sun and Uranus; this characteristic seems to rule out the existence in this sytem of a solar system which closely resembles our own.

If we were to send signals to any stars in the neighbourhood we should consider the Alpha Centauri system as only a borderline candidate.
There are a few other stars a little further away which might be better candidates (such as Beta Canem Venacitorum and 18 Scorpii) but it would probably be prudent to wait until some terrestrial planets have been detected in some of these systems before trying to send a message.

captain swoop
2006-Sep-06, 11:28 AM
1 There is lots evidence (most of it rejected by mainstream science for good reasons) that some of the ET are hostile.

Apart from Sci-Fi what evidence would that be?

Ronald Brak
2006-Sep-06, 11:34 AM
Why spend big bucks to attract aliens that may reguard humans as a food source or otherwise cause us great grief?

This reminded me of a science fiction story I once read where a converstation went something like this:

HUMAN: Do you want to eat us?

ALIEN: That is impossible. Our methane based biochemisty makes it impossible for use to make use of the compunds your bodies are comprised of.

HUMAN: If you could eat us, would you?

ALIEN: Oh yes.

BigDon
2006-Sep-06, 11:57 AM
Hate to tell you this Duane, but ever since the invention of broadcast media, (Radio and Television) we have been sending a message to the nearest stars. We put out more RF than a small star. Which ought to be curious in its own right.

I liken it to a gnat landing in a still brook and vibrating it wings, sending out minute ripples in all directions. If trout turn out to be a myth, no harm done.

Ronald Brak
2006-Sep-06, 12:05 PM
It's true that we are sending out signals, but apparently they don't get too far before they are drowned out in the background radio noise of the galaxy. Even if a nearby civilization was putting out as much radio waves as earth we wouldn't be able to detect it. SETI relys upon delibrate radio transmissions beamed out by lifeforms that are interested in making contact with civilizations such as our own. We can only guess at how likely they are to want to do that.

ZaphodBeeblebrox
2006-Sep-06, 12:08 PM
This reminded me of a science fiction story I once read where a converstation went something like this:

HUMAN: Do you want to eat us?

ALIEN: That is impossible. Our methane based biochemisty makes it impossible for use to make use of the compunds your bodies are comprised of.

HUMAN: If you could eat us, would you?

ALIEN: Oh yes.
In The Story I Read, they Were Sulphur Based Spiders ...

Luckily The Woman Who Asked The Question, Was Quickly Informed ...

"Maybe they thought we'd be insulted if they didn't offer to eat us."

:sick:

Ozzy
2006-Sep-06, 12:22 PM
Do and TV radio waves travel at the speed of sound and if so how far would the radio signals of the 1920's have travelled so far?

If a transmission tower has been broadcasting for the past 80 years in a direct line to a distant planet, would an advanced civilization be able to listen to and eventually watch a continuous stream of our culture?

Image their impression of us if they only had one TV or Radio Station ...MTV, Fox News?

Ronald Brak
2006-Sep-06, 12:24 PM
In The Story I Read, they Were Sulphur Based Spiders ...

That's it. I read it a long time ago so I couldn't remember any details.

antoniseb
2006-Sep-06, 12:26 PM
I agree with eburacum45. If your intent is to try and signal beings on planets orbiting nearby stars, why not wait till later in this century, after we've had a chance to build and operate terrestrial planet-finding telescopes, and have had a chance to more closely analyze which such planets seem to be harboring life?

We can then build sufficiently large radio telescopes to be able to detect artificial radio transmissions, and THEN, we can try budgeting your message blaster. Really there is no hurry on this one.

Argos
2006-Sep-06, 12:38 PM
The IAU frowns at active SETI. We are essentially censored regarding extraterrestrial communications. You can make a call to your German friend over the Atlantic, but youre not allowed to make friends across the galaxy. The IAU intends to take the case to the UN to establish a protocol concerning (i.e., officially forbiding) deliberate sending of messages to "the outside".

Its kind of a selfish position: were eager to receive an interstellar message, but we wont issue any.

There has been many projects attempting (or claiming to attempt) to send an extraterrestrial message. I can think of the Millenium project, a Brazilian project called Extracom, and a few others, besides the "message" already sent by F. Drake from Arecibo, in the 60s.

Argos
2006-Sep-06, 01:13 PM
Here´s the "cocoon" argument (http://www.setileague.org/editor/index.html) [lets-keep-silent-in-our-cozy-shell]

And more ASETI bashing (http://www.setileague.org/editor/actvseti.htm)

Romanus
2006-Sep-06, 01:43 PM
It's been done. In 1999 and again in 2003, "Cosmic Call" sent out complex messages to several stars that they thought were suitable for intelligent life. Here are links:

http://www.matessa.org/~mike/dd-pr.html (Cosmic Call 1999)

http://www.cplire.ru/html/ra&sr/irm/CosmicCall-2003/index.html

I can understand those who believe that we could seal our doom by active SETI, but I really have more important things to worry about than a hypothetical alien invasion.

neilzero
2006-Sep-06, 06:15 PM
The not very admisable evidence is perhaps a million experiencers, some of whom are well educated apparently resonsible persons. Most have seen what they thought was an ET space craft, but thousands claim to have received messages, by channeling or face to face conversations. Several hundred claim to have handled and/or tested hard physical evidence which was seized by authorities, stolen and/or skilfully debunked.
Hundreds of experiencers have been ordered to stop talking, perhaps 50 were threatened with bodily harm or other punishment unless they recant. Several who kept talking, died mysteriously. All this is evidence, but not proof, as reasonable alternative explanations can be concocted, sometimes dishonestly. The debunkers have been caught in lies about as often as the experiencers. Some of the experiecers have concluded that pubblicity is bad for their career and/or their health, and have since stoped talking. Neil

Lurker
2006-Sep-06, 06:59 PM
The not very admisable evidence is perhaps a million experiencers, some of whom are well educated apparently resonsible persons. Most have seen what they thought was an ET space craft, but thousands claim to have received messages, by channeling or face to face conversations. Several hundred claim to have handled and/or tested hard physical evidence which was seized by authorities, stolen and/or skilfully debunked.
Hundreds of experiencers have been ordered to stop talking, perhaps 50 were threatened with bodily harm or other punishment unless they recant. Several who kept talking, died mysteriously. All this is evidence, but not proof, as reasonable alternative explanations can be concocted, sometimes dishonestly. The debunkers have been caught in lies about as often as the experiencers. Some of the experiecers have concluded that pubblicity is bad for their career and/or their health, and have since stoped talking. Neil
Um... yeah... as you say there is no evidence... There is a lot of hearsay here, but you are right there is no evidence. When you have some maybe you will be listened to...

hhEb09'1
2006-Sep-06, 07:44 PM
Do and TV radio waves travel at the speed of sound and if so how far would the radio signals of the 1920's have travelled so far?They travel at the speed of light, so something sent in 1926 would be 70 lightyears away.

phunk
2006-Sep-06, 08:18 PM
And at the power level of 1920's technology, it would probably be undetectable without an antenna the size of a planet.

jlhredshift
2006-Sep-06, 08:28 PM
And at the power level of 1920's technology, it would probably be undetectable without an antenna the size of a planet.

And even then because the Earth rotates it would be a sporadic signal, but then it would have a regularity to it....

Hmmm...

Ozzy
2006-Sep-07, 02:41 AM
How long would the transmission window of a TV signal be as the Earth rotates? They might only be getting the end credits of the Simpsons.

PhantomWolf
2006-Sep-07, 04:37 AM
"We want McNeal!" "We want Single White Female Lawyer!"

astromark
2006-Sep-07, 11:11 AM
Look at where this thread is wondering.....
'Why don't we just blast out a message,? simply put the length of time our message takes to get any where. Is reason enough not to bother. secondly the strength and type of signal sent are not clearly going to be recognized as an attempt to communicate. We know nothing of the perspective recipients. We can not be sure there are any. Just looking in this local group of this galaxy does not realize a answer. On this subject. I do not think we know with absolute certainty that the Alpha Cent., double does not have planets in the right zone to support life. Do we,? But even at this distance its a almost nine year, at light speed conversation. I sagest humanity needs to wait until our science advances our ability to communicate quicker than this.

ZaphodBeeblebrox
2006-Sep-08, 07:01 AM
Look at where this thread is wondering.....
'Why don't we just blast out a message,? simply put the length of time our message takes to get any where. Is reason enough not to bother. secondly the strength and type of signal sent are not clearly going to be recognized as an attempt to communicate. We know nothing of the perspective recipients. We can not be sure there are any. Just looking in this local group of this galaxy does not realize a answer. On this subject. I do not think we know with absolute certainty that the Alpha Cent., double does not have planets in the right zone to support life. Do we,? But even at this distance its a almost nine year, at light speed conversation. I sagest humanity needs to wait until our science advances our ability to communicate quicker than this.
Sounds Liike a Plot Idea I Was Workin' on ...

Aliens Implement a 9 Year Reverse Tiime Delay onto an Ordinary Communications Dish ...

Unfortunately, their Planet's Governments Fall Into Inter-Necine War and Terran Scientists Wind Up Having to Duplicate their Device, In Order to Stay in Contact!

:think:

captain swoop
2006-Sep-08, 10:45 AM
fall into Inter-Necine war' What do you think they are in at the moment?

DuaneW
2006-Sep-08, 05:51 PM
The fun, yet aggravating, thing about astronomy is that one topic invariably leads to another, hence my comments below:

I don't see a problem with intelligent life evolving on a planet orbiting a red dwarf star. Yep, I've heard all the arguments: The flare star argument and the tidally locked argument are two of the ones that stand out. However, I'm sure that intelligent life can find its way through both mazes. After all, didn't intelligent life evolve on Earth in spite of (or perhaps because of) catastrophic meteor impacts, ice sheets that regularly advanced from the poles down to the mid latitudes, and the emergence (and regretful comeback) of Swing music? (haha). And let's not forget that an Earth like moon could conceivably orbit a Jupiter sized world, which in turn could orbit around a small star, which could possibly eliminate both problems.

Of course, sending out messages to stars much larger than our sun would be a waste of time. I doubt Rigelians have had time to evolve under that particular blue blast furnace, and any Betelgeusians still alive are sitting under miles of molten rock fanning themselves and saying "Lawd, this weathuhhhh!!!"

But stars the size of our Sun or smaller, even the tiny ones at a hundred Jupiter masses, are so numerous that we'd be foolish (in my view) to discard any one of them, unless observations rule out any local planetary bodies.

To me, the only real impediment is cost, though after reading about the Cosmic Call in the links above, perhaps it's more a matter of will.

As for our alerting the Universe to our presence making a meal out of us…. Well, we'll just have to :dance: like it's 1999 then, won't we?

Wombaticus Rex
2006-Sep-08, 05:55 PM
Regarding radio from the 1920s, are those signals still coherent? Is there any degradation?

ZaphodBeeblebrox
2006-Sep-08, 09:52 PM
fall into Inter-Necine war' What do you think they are in at the moment?
Actually, In The Plot as it Stands, their Planet is Enjoying a Rare Peace, akin to the 1920s or 90s, Perhaps Even as Notable as The Concert of Europe, a Calm Before The Storm if you Will ...

Then, One of Those Brushfires that NEVER Gets Quiite Stamped Out Even in The Most Peaceful of Periods, Flares Into Horrible Liife and Drags The Whole Planet Into a Nuclear War ...

By The Tiime The Dust Finally Settles, a Fascist Dictatorship Rules Over their Whole Solar System, King of All it Surveys, But Those Pesky Humans Threaten to Get in The Way!

:evil:

jlhredshift
2006-Sep-08, 10:07 PM
Regarding radio from the 1920s, are those signals still coherent? Is there any degradation?

The inverse law applies so the signal is definetely much much weaker. But, also consider that those signals were broadcast from antennas that were primarily vertically polarized, i.e. aimed at the horizon. Therefore the strongest part of the signal had to first traverse a lot of atmosphere and could experience some reflection episodes before escaping to space. In the fifties I could pick up BBC london late at night on a cheap shortwave if I held it just right in my bedroom window. But, the signal would come and go with the movements of the atmosphere. At a distance of 86 ly I am sure the same variability would apply but at a much much lower signal strength, plus adding in the Earth's rotation it would come and go completely.