It's possible, look at all the satellites we have launched to just fly around other planets. Maybe "they" have even plunged probes into our atmosphere, oceans, and land masses, and taken soil, air, and water/ice samples... it gets eerie when you think about that doesnt it? Here we are thinking we are a superior group, when they may be able to hide "underground" when we send a satellite, or probe so we really can't tell how far behind we really are.... I am actually facinated with the thought of space exploration/travel. I am a Ham Radio Operator, and have enjoyed many contacts using satellites we built, and had launched for that purpose. I also have assisted in receiving signals from craft we have launched to make sure the systems were operating, In the 60's and early 70's we could actually listen in to much of the radio traffic on a regular shortwave radio, or the good old Ham rig. We can still listen to some of it, but not like it used to be. At any rate, it always makes for some good chatter, movies, and books.