Look For Extraterrestrial Civilizations (Don't Just Listen)

That makes no sense to me at all. Anybody making a radio transmitter is gonna chose a frequency that doesn't have alot of natural generators to minimize interference.

It is also the "quiet" spot for receiving extra solar system RF. It is an excellent frequency to study the universe and subsequently look for artificially generated signals.

There are two real sources of noise that limits the radio astronomer’s ability to search for very weak signals. (1) The Galactic noise halo interferes with us below 1GHz and (2) noise due to earth’s atmosphere interferes with us above about 10GHz. This pretty much keeps all SETI searches (at least radio ones) between 1 and 10GHz. Further inside this range, (from 1.4 to 1.7GHz), the noise drops even further to nearly the 2.7K microwave background permeating this universe. This is why most of the SETI searches are around the frequencies that the H (hydrogen) and OH (hydroxyl) molecular masers emit (1.42 and 1.64GHz respectively). This is the so-called water hole “OH H” you hear astronomer talk about occasionally. (Tell me scientists don’t have a sense of humor) :-)

However, this is not fraught with its own set of problems. Much of our own radio transmissions do not fall within this range. Also this is one of the coveted frequencies of radio astronomers, thusly we have international treaties to not broadcast at these frequencies since they would interfere with radio astronomers. So here we are looking for signs of a narrowband signal heralding the fact that intelligent life is not wholly constrained to our tiny little planet at these very frequencies.

Just imagine another tool building species that ends up developing radio and radio astronomy that may also recognizes the importance of this 21cm band. And they also may instigate a SETI search using these same bands such as we do. So here is the question. Would they hear us at those frequencies? They are the very ones that we are not transmitting on at all. I could just see 500 races all looking for each other at the very frequency band that none of them are transmitting on due to the very nature of its importance for the exploration of the universe.

The big problem with listening for transmissions that are intended for detection by beings on other planets is that we have to be listening when their transmission arrives. To my knowledge, there is no concerted effort here to broadcast messages to other worlds, so why would we assume that anyone else is doing it? It seems to me that other means of detecting signs of intelligence needs to be devised, ones that would depend only upon the mundane day to day goings-on in a technological civilization. Like detecting alien police radars or microwave links.

This is exactly what we are doing. :-) What SETI looks for is the narrowband carrier that radio signals ride on. We are bleeding radio into space in all directions. Possibly another race may be doing the same thing. Why the search I am involved in is looking at millions of frequencies simultaneously. Ups the odds just a wee bit.

My belief is that until we have learned to communicate with the other civilized species inhabiting earth we need not work to hard trying to contact ET.

The most important are honey bees, ants and termites with bees heading the list.

We have barely broken a few of their codes and can't communicate the other way at all. They definitely communicate with each other at a high level.

The probability the alien will be inscets is pretty high.

Maybe there's a reason they don't want to be heard throughout the galaxy.

There's an interesting technique invented for digital radio transmission that might become widespread. Each block of 4 bits is mapped to one of 16 different complex signal patterns that are mathematically chosen to add up to white noise. When decoding this signal the closest pattern is selected, allowing for a weak signal to get through a very congested and noisy environment. Add in data compression and the signal appears to eavesdroppers as random and devoid of any intelligence. This may be another reason SETI isn’t finding much out there.

The socialists better hope we never discover another civilization because after the initial euphoria wears off, widespread fear will set in. We will be forced to develop our military and space technologies at the expense of social spending. Since we will have little information on the level of threat we face we will have to assume and prepare for the worst.

noise due to earth’s atmosphere interferes with us above about 10GHz.

There's a point to be made there..

Any civilization still broadcasting from within their own atmosphere isn't ready for contact yet...
Civilizations that have made it outside of their planetary bounds, and have done so consistently would be a minimum requirement for contact..
In fact, our civilization will probably have to be able to include extra-planetary movement, industry, commerce, recreation, etc.. into our world civilization structure before we will be worthy of notice..
There may be one of those ST federation "non-interference" rules in effect..
I.e., until a world is ruled "space-faring", contact is prohibited..

The socialists better hope we never discover another civilization because after the initial euphoria wears off, widespread fear will set in.

I would be more worried about certain world religions..

The discovery / confirmation of intelligent technologically advanced life on other planets would result in massive religious back-lash..
Some will have to completely revise their view of G_d, unviverse and everything.. including religious dogma developed over the last 2000 years..

It could result in the end of religious views as we know them, religious wars, utter chaos, or religious "revelation" of a whole new way of thinking.. a new wave of missionaries with an extraterrestrial calling.. who knows??

The digital filtering thing is interesting, a good way to get rid of the "white noise"..
But what if the white noise IS the message?

I'd like to see a more graphical approach..
Use a 1 to 2 Mhz bandwidth and scan the frequency ranges for information contained in graphic form.. Like the Golden Mean, ( phi ) and search for anything resembling graphic representations in standard height/width/depth formats.. ( both 2 dimensional and 3 dimensional arrays..)

It's probably being done, and I'm simply unaware of it, but I'm a graphics oriented person, not a number cruncher..
If I were trying to communicate with someone I had no lingual or cultural reference to, I would choose graphics to start..

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