We have been trying to contact aliens (the generic term for extraterrestrial intelligent life forms) for decades. Not just in a single way. We have used several ways to contact or even just find out if they are out there. Some are passive, some could be considered invasive.
SETI-Search for Extraterrestrial Intelligence is a vast array of radio telescopes as well as some gigantic single radio telescopes. This is the passive search. We are just listening for any sign of radio waves or communication. We shoot millions of them into space every day with TV, radio, cell phones, and the inter-net. We are betting that intelligent life would be sending similar energy into space. Not a message specifically to us, but a random signal we might pick up. To date, we haven’t had a lot of luck.
The invasive version is in the probes. According to John Hopkins University Applied Physics Laboratory, Voyager 1 left our solar system and entered interstellar space in 2003. Both Voyager probes contain gold discs that contain information about Earth and the human race, including a map back to Earth. This is where the problems may begin.
Contacting aliens seems like a really good ideal on paper. We would prove that we are not alone, validate all the “tons” of money that has been spent on the space program and various other things.The concern is, what if the aliens that discover it are not the movie version of ET that likes Reeces Pieces?
There is a very real chance that alien life forms have been watching our transmissions for years. It was fine as long as we stayed in our neighborhood. Now that we are leaving it, bad things might happen.
If the aliens that we make contact with happen to be hostile, or want to stop the spread of violence through the cosmos, we have a horrible track record. Between the actual news about wars and the movies that come out of Hollywood, we are a violent species.
If they are peaceful and don’t want violence to spread, the images that we have been broadcasting over the last hundred or so years are reason enough to exterminate us the way we would termites.
If they have full hostile intentions, we don’t stand a chance. We have given them a map back to our home world. We are a splintered species that can’t get along with each other let alone provide a unified front against an invasion. Even if a miracle were to happen and all the countries of the world came together, would the worlds top of the line weapons stand a chance against a life form that is capable of interstellar space travel? If they can power a starship those distances, it stands to reason that they would have weapons infinitely more advanced than ours. Basically, Star Wars would not even hold a candle to what they may be capable of.
This is the doomsday, worst case scenario. If the aliens are completely benevolent and their intentions are the best. They come in peace and want to endow us with technology that will make our lives easier, the danger is not completely over.
Even with the aliens carrying the proverbial olive branches of peace, they could very likely have bacteria and viruses that the human species have absolutely no immunity to. While they are trying to help us they could wipe out the entire species (or even life on the planet).
The famous Stephen Hawking made a statement about alien encounters, and I paraphrase, meeting a brand new culture (in this case aliens) may not turn out well for the humans. Look what it did for the Native Americans when the Europeans arrived in the New World.
Finding proof that there is life out there would be fantastic. If we could communicate with them, it would be even better. Before we meet face to face we need to know exactly what their true intentions are (the Earth is full of raw materials and we may be nothing more than an ant hill to them) as well as come to an understanding of the biological ramifications.
It does go both ways. Even though it was science fiction, it could still happen. War of the Worlds showed us that our common cold could possibly wipe out the visitors and even cause a war between species.
This is an area that we need to tread very, very lightly indeed.