If you are already a member of the AAS
Members of the American Astronomical Society may become Regular Members of the Historical Astronomy Division for an annual fee of $15. Please contact the AAS Membership Department at firstname.lastname@example.org or call +1-202-328-2010 x101 to pay by credit card.
If you are primarily a historian and not a member of the AAS
Members of other professional societies may become Affiliate Members of HAD for $20 annually. To become an affiliate member, you must be a member of another professional organization actively concerned with historical astronomy (such as History of Science Society, Society for the History of Technology, American Historical Association, etc.). You will need to be nominated by at least 2 AAS members of the Division and approved by the HAD Committee. Affiliate members will enjoy the same rights and privileges as other members except that they will not be able to hold elective office within the Division. To become an Affiliate Member of HAD please download and fill out the application form, and send it, preferably via e-mail, to the HAD Secretary-Treasurer (address).
If you are a physical scientist who wishes to join both the AAS and HAD
Please see information on the AAS website.