About John G. Wolbach Library

The John G. Wolbach Library combines the collections of the Harvard College Observatory (HCO) Library and the Smithsonian Astrophysical Observatory (SAO) Library, forming one of the world’s preeminent astronomical collections. 

You can read a full introduction to how to get started making use of Wolbach's resources and space on the Library Introduction page.


The principal subject areas contained within the Wolbach Library collection include astrophysics and related topics in physics, chemistry, applied mathematics, geophysics, and engineering (see Wolbach Collections Development Policy).  The Wolbach Library collection is comprised of materials of all types including books, journals, maps, charts,  microforms, and audio-visual resources, which total over one hundred thousand items in all. Special Collections within Wolbach Library include:  the Astronomical Institutions (AI) Collection which contains historical publications issued by observatories world-wide; the Harvard Astronomy Department Dissertations Collection; an international Astronomy/Astrophysics Thesis Collection; and the papers resulting from the Harvard Astronomy Department Research Tutorials. Some Wolbach Library material is also housed in the Harvard Depository.  Most items held by Wolbach Library are discoverable via the HOLLIS catalog.


The Wolbach Library provides shared resources to support the CfA community's continuously evolving needs. Wolbach Library staff build, organize, manage, house, and preserve collections of physical and digital research artifacts; offer reference services and consultation; provide services in online literature searches and interlibrary loan requests; and contribute to and draw from remote databases, including the NASA Astrophysics Data System (ADS). The Wolbach Library participates in local, national, and international networks and cooperative activities to promote scholarly advancesment, the sharing of information, access to recorded knowledge, and the empowerment of the astronomy and astrophysics community.

Our current and future priorities are to:

  • Facilitate the creation and sharing of new knowledge in Astronomy

  • Lower technical and social barriers that negatively impact the CfA community's ability to achive it's goals

  • Promote the work of the CfA community both internally and externally

  • Develop digital projects and priorities that continually challenge Wolbach library staff to excel at an international level

  • Seek strategic collaborations to ensure the sustainability of Wolbach's programs, services, and projects

  • Promote open science through outreach and training programs


The HCO collection results from the traditional exchange of scholarly works between observatories in the 1800s, and expanded further as commercially published materials became available. The SAO Library dates back to about 1959, when items were selected from the collection of astronomical material in Washington, DC and moved to Cambridge, MA. In 1975, the two libraries, which had been housed in separate parts of the Observatory, were merged into the Wolbach Library in the Perkin Building. In 1992, the administration of the HCO and SAO collections was merged under one director and staff.