In my understanding, Science Communication is a fundamental part of Science. We live in a society that is highly dependent on several forms of technology while being disregardful -- sometimes even suspicious -- towards Science. In these times, we astronomers have an important role to play, because our research captivates attention and imagination in a unique way.
To bridge the gap between scientists and the society we have to step forward and be proactive at explaining what we do. Because Science is not complicated; in fact, in a typical reductionist approach, it is as simple as it can be! We need to break up with the tradition of presenting Science as a collection of experiments performed long time ago by some distant, authoritarian figures. We need to start teaching Science as a verb. By teaching the tools of reasoning, we empower people to make their own decisions, to choose their own path. As those who had the chance and privilege of higher education, we owe a duty towards the rest of our society. Not because we are better in any way; if fact, exactly because we are not better in any way.
You can find one of my latest Exoplanets outreach talk and a talk I gave on the subject of public funding of Science, with plenty of support material, in my bitbucket account.