Alien Bad Guy Bias
The Bad Guy Bias applies to Earth signals to aliens. From the NYT:
The makers of the new movie “The Day the Earth Stood Still” have arranged for it to be beamed into space on … the same day the movie opens here on planet Earth. … Dr. Shostak, who was a consultant for the new movie … [says] there are some people, he acknowledges, who might worry that broadcasting “The Day the Earth Stood Still” could be inimical to our interests. He added, “I think that if these people are truly worried about such things, they might best begin by shutting down the radar at the local airport.”
Shostak is right; compared to intentional signals, unintentional signals are a million times larger:
There are three large-dish instruments in the world that are currently employed for doing radar investigations of planets, asteroids and comets: ART (Arecibo Radar Telescope), GSSR (Goldstone Solar System Radar), and EPR (Evpatoria Planetary Radar). Radiating power and directional diagram of these instruments is so outstanding that it also allows us to emit radio messages to outer space, which are practically detectable everywhere in the Milky Way. This dedicated program is called METI (Messaging to Extra-Terrestrial Intelligence) …
Over all the radar astronomy history … The total area of the sky illuminated by [radar] transmissions is about 0.022 steradians (sr). … The total area of sky illuminated by the METI transmissions is … 2000 times less … Total duration of time of radar transmissions exceeds the overall time interval of the METI transmissions by a factor of 500. Therefore, we can conclude that the probability to detect the radar astronomy transmissions by a hostile super-civilization is 2000 x 500 = 1,000,000 times higher than that of the METI transmissions.
So, if someone is concerned about our detection by an aggressive super-civilization (so-called METI-phobia), first of all one has to prohibit not the METI, but the radar astronomy. However, one can not prohibit it because the radar astronomy is an important and indispensable component of the asteroid hazard and defense system. But most radar astronomy has little to do with asteroid defense.
Seems to me we should be more explicitly considering these negative costs of radar astronomy. Some argue we shouldn’t worry about radar astronomy because Earths O2 spectral line has emitted a signal hundred billion times stronger. But life be far far more common in the universe than radar astronomy capable life.
Not sure I agree with this, but here is one argument that worrying about aliens might not be "bad guy bias", but rather a very reasonable worry (not something we should spend every day in fear of, more like the worry that we might be wiped out by an asteroid or comet hitting the earth without alien intervention)
http://sites.inka.de/mips/r...
While the huge number of star systems out there with planets makes it highly likely that there is life elswhere, and some form of intelligent life somewhere out there, the lack of any pickup of anything looking like an intelligent transmission by the long-running SETI project is not very encouraging about there being much of the latter anywhere nearby in our galaxy, or even pretty far away in our galaxy. Somebody might be listening to us, but they do not seem to be sending anything out on their own. Given how difficult it is to get life going and then to get multi-cellular life going, intelligent life out there may in fact be very scarce.
Also, as long as Einstein remains correct and the speed of light is an essential limit to velocity, interstellar travel remains very unllikely or difficult.
Of course, if one wishes to accept that perhaps there are much higher civilizations than us, able to overcome the speed of light limit, and even some kind of galactic or even inter-galactic civilization that maintains some kind of higher order as in so many sci-fi series, then it would not be illogical to have had an outbreak of visitations after 1945, coinciding with the big outbreak of UFO sightings, not all of which have been explained, given that in 1945 we humans set off explosive nuclear weapons, something that a higher order interplanetary civilization would presumably keep track of in "developing" plantary civilizations, indeed, the theme of the original "The Day the Earth Stood Still."