Here we are: a signal for extraterrestrial civilizations

Would it be possible to alert extraterrestrial civilizations to our presence in the universe? Yes, says a feasibility study that was carried out by MIT doctoral candidate, James Clark, and was published in The Astrophysical Journal. Clark combined two already available technologies: a strong laser with an output power of 1 or 2 MW, similar to, for example, the U.S. Air Force’s Airborne Laser, and a large telescope with 30-meter (100-feet) or 45-meter (150-feet) optics, like those already in c...