So why bother having an official journal if everyone can post for free on the arXiv instead?
As scientists ourselves, we at the AAS journals don’t see our role as simply republishing our authors’ work with better typesetting. Instead, we feel that the critical mission of the AAS journals is to increase the scientific integrity of the field. To us, achieving this means not only providing the obvious services — such as acting as gatekeepers for pseudoscience, facilitating peer review for manuscripts, and providing long-term preservation of articles and data — but also the less obvious services that improve the quality and reach of manuscripts published with us.
As astronomy is driven more and more by big data and statistics, ensuring that these aspects are correctly handled in manuscripts will systematically improve the quality of research published in the field. For this reason, the AAS journals employ two full-time data editors, Drs. Greg Schwarz and Gus Muench, who review submitted manuscripts and edit the data, figures, and software citations for those articles that contain significant tabular or other data material. Our data editors provide many forms of author support, including developing and supporting AASTeX and documenting best practices for using online repositories and data linking. They also set up and maintain new initiatives for the journals, such as interactive and animated figures, and they work with in collaboration with community archives and science platforms to improve data linking.

The homepage of AAS Nova, a website through which summaries of recent AAS journal articles are shared with the community.
Additionally, the AAS journals have a dedicated statistics editor: astrostatistician Dr. Eric Feigelson, professor at Pennsylvania State University. The statistics editor reviews all AAS journal manuscripts that include a significant statistical component, offering authors recommendations on how to strengthen the statistics of their studies in accordance with current best practices in the field.
In the interest of broadening the reach of articles published in our journals, the Society developed AAS Nova, a website designed to help disseminate our authors’ work to the larger astronomical community and the broader public. AAS Nova editor Dr. Susanna Kohler produces and edits summaries of research articles that appear on AAS Nova, ensuring that this work is shared with other astronomy researchers, science journalists, and the general public.