For many decades now there has been a group of human been searching for signs of civilizations out there. So far there has not been any luck with it. Why I do not know. But I do think that how this search is done might be wrong. That is searching just one band of 1420Mhz, or the Hydrogen line (wiki). While this frequency might be optimal for space travel, I do not believe that is being used on a planet. The reasons being the same as here on Earth. It is impractical for communications.
I base my suggestion on the space travel and 1420Mhz on the Wow signal that was detected in the year 1977.
To search for civilization it is my opinion that the search must be done on frequencies that we human already use. But the problem here is the local noise, that is transmitters on Earth. But I do not think that problem cannot be crossed with good mapping of the local area frequencies in use. Along with frequencies that might bonce off Earth atmosphere.
The estimated range for radio signal from Earth is about 20 light year according to this study here. So mapping of yellow stars and similar types of suns in that range should not be too difficult. As the nearby stellar neighborhood is well known and has been for a long time now. But the question that remains unknown is if there is a civilization out there, does it have the technology to broadcast strong radio signals out into space. It might well be that a civilization is out there, but it might be on a stage that is equal Earth in 19th Century, or something earlier. Or they might well have passed us on the technological level and have stopped broadcasting radio signals into space.
This are all questions we might not get answer to. But if a radio signal is found from a alien civilization is found. It might give us a great idea what is out there. But I am sure that getting that type of signal is not going to be easy. In fact, I am sure that it is going to be real hard to do so. But it is not impossible, just hard. I am up for that challenge from my point of view. I hope that others are too.
I find that there are enough space blogs that cover the natural phenomena that can be found in Space. But nobody covers this aspect of space, since it has been made ridiculous for many decades now. We might not be able to communicate with a alien civilization out there. But we sure can listen to them if we find there signal.
This is what I am going to do with this blog. It took me long term to figure out what to do with this blog. The course has now been set. I welcome all my new readers to this blog. You know now what this blog means and what it stands for. I hope that you enjoy to read this blog, as I have writing it.