[acecharly (OP)]

When SETI scans for a signal from space that may be an alien race do they cover much of a range of signals and would it not be possible if they didn't that they could record say a 10 minute batch of information and then go through all of it checking every band possible?

[Bored chemist]

I guess SETI@home is one of the best known and biggest searches, and they pretty much do what you suggest.
Here's their web page about it.
http://seticlassic.ssl.berkeley.edu/about_seti/about_seti_at_home_2.html

[acecharly (OP)]

Cheers BC 

[Soul Surfer]

Receiving signals is quite a good possibility eventually but the probability is that all signals will originate much too far away to allow two way communication within a reasonable period.  On a galactic scale 100 light years is in our back yard and 10 light years is just about as close as possible.  that is 2way communication over these small distances will take 200 or 20 years.

[syhprum]

I have always understood interstellar communication between planetary systems equipped With Arecibo sized antennae and multi megawatt transmitters would be possible up to 1000 LY but utterly futile of course.
 

[percepts]

Given the amount of violent tv and film broadcasts made (including war of the worlds) plus all the mindless daytime tv shows and soaps broadcast, why would any technologically and quite possibly far more intelligent beings than humans actually want to contact us having seen all the brainless stuff we've been pumping out to them for the last 50+ years. Morbid curiosity perhaps?

[syhprum]

There is no chance of any of our regular TV being received at inter stellar  distances the ERP is much to low and the required bandwidth much to great.
Communication would only be possible with megawatt transmitters and Arecibo size antennae at one or two hertz bandwidth.

[RD]

Saw this recently ...

New Project Will Send Your Messages to Aliens in Deep Space

http://www.space.com/21528-alien-intelligence-messages-lone-signal.html

[percepts]

There is no chance of any of our regular TV being received at inter stellar  distances the ERP is much to low and the required bandwidth much to great.
Communication would only be possible with megawatt transmitters and Arecibo size antennae at one or two hertz bandwidth.

According to whose knowledge, humans or far more technologically advanced aliens?

[syhprum]

Regardless of the of the intelligence of the little green men you cannot buck the laws of physics if you don't have enough ERP you don't get any pictures regardless of the receiving antennae size or receiver noise temperature.

[galaxysim]

I was thinking on this the other day.

We should perhaps be looking for LGM high above the galactic plane. If you want to send signals across vast distances it makes sense to build transmitter stations a 1000 light years above  and below the galactic plane.

LGM would do this for similar reasons that we have some GPS & communication satellites in high orbit

Now if Aliens do exists and they have a colonized many worlds over millions of years these worlds will be slowly swirly and bobbing around. Over time the expansion would no longer resemble a sphere, but a milky swirl like shape. (everything in the galaxy is moving ) That would be a good reason to have transmitters high above the galactic plane. They would send research stations above the galactic plane  just to get a good viewpoint anyway.

It would make a lot of sense that they use this vantage point to broadcast and listen for other races.

We are perhaps looking in totally the wrong place...we can, with some calculation work out where those top 1000 vantage points might be.  If the LGM home world was at x,y,z co ordinates then their  transmitters above and below the galactic plane would be located at a,b,c co ordinates. ( dark spots with clear lines of sight, no pesky galaxies in the background or dust clouds in the foreground )


If advanced aliens do exist, some will have expanded their territory. They will have stupendously massive and sensitive receivers located above the galactic plane. They may have spotted oxygen in our atmosphere a billion years ago. I can imagine a frustrated LGM operator banging his head on the console ' pick up the phone earth dummies'...."i got smoke billowing out of the transmitter, there is only so much i can do to help" ...you never know, lol

...and if this is the case, i want a very very large case of beer sent flocking my way!


now armed with the obvious, radio astronomers of the world go get busy