A commission of the International Astronomical Union published in October 2007 the first issue of the journal Communicating Astronomy with the Public (CAP Journal). Since then, it has become a very interesting 100% free (online and in print) peer-reviewed journal devoted to science communicators, in particular, to those specialised in astronomy. All the contents may be downloaded in PDF format, at low or high resolution.
While the principal task of an astronomer is to further our knowledge of the Universe, disseminating this new information to a wider audience than the scientific community is becoming increasingly important. This is the main goal of public astronomy communication: to bring astronomy to society.