|About the Project||What is a Parallax?||Search||Browse||Allegheny Observatory||Links||Help|
The following list of help topics will link you to the appropriate section. To return to the list, click the back button on your navigation toolbar or scroll to the top of the page.
Browsing the Volumes
To browse the volumes by page image, go to the Browse page and select a volume.
The Table of Contents for the online version of the volume will be displayed. This URL can be bookmarked in your browser for recurring access. The Table of Contents contains links to major sections of the volume, including title page, table of contents, issue number, tables, observations, illustrations, and index. Clicking on a link will take you to that particular section of the volume.
Navigating and Viewing the Page Images
When you view a page image, you will also see a separate navigation frame at the bottom of your browser. This is what the various parts mean:
Please note the appearance of the page image. What you are viewing is the actual scanned image of a page from the original volume. You should be aware that the format of the Parallax Project digital text poses certain problems:
Several of the volumes contain introductory material, organizational history, etc. as front matter. From the volume's table of contents page image, use the Previous Page and Next Page buttons to view this text.
Searching the Volumes
The Parallax Project offers selective searching of the star data contained in the Publications of the Allegheny Observatory. The full-text is not searchable; therefore, it is important to use the Browse feature to view and navigate the contents of the volumes. See About the Project for information about the data-gathering process.
To search for selective star information, go to the Search page. You can search for star information by one or more of the following fields:
Allegheny Observatory (AO) Number: Search by unique identifier (i.e., running number) assigned to the individual stars by staff at the Allegheny Observatory. Enter an integer from 1 to 4 characters. This search will only return one result.
Star Name: Search by name of the star. The search will automatically truncate. For example, a search on andr will return a list of all Andromedae stars. Do not use abbreviations for star name. Use the virtual keyboard to enter Greek characters that precede an alphanumeric star name. (Note: some older Web browsers might not display the Greek characters correctly; please consider upgrading to the latest version of your browser.) For example, to search for α Andromedae, enter α andr (be sure to place a space after the Greek character). To search for a star name represented by superscripts and/or subscripts, you will have to enter the proper HTML code. For example, to search for star name W2 18h 979, enter W<sub>2</sub> 18<sup>h</sup> 979.
Right Ascension (RA1900): Search by the approximate right ascension of a star (1900 equinox). You must enter the entire position: hours, minutes and seconds. For example: 0:3:12 or 00:03:12 for α Andromedae. Please note that where RA values in the volumes included fractions of minutes, those fractions were converted into seconds for the purposes of consistency in the database.
Declination: Search by the approximate declination of a star. You must enter the entire position: degrees, minutes and seconds. For example: 28:32:00 or 28:32:0 for α Andromedae.
Parallax: Search for the parallax value for a star(s). Enter the arcsecond (include the decimal point). For example, a search on 0.0260 or .0260 or 0.026 or .026 will retrieve the same results. By default, a search is performed on a specific parallax value (e.g., equals). Use the pull-down menu to perform a search on a parallax value that is greater than or is less than the arc second entered in the search box.
Parallax Error: Search for the probable error of the parallax determined for a star(s). Enter the arcsecond (include the decimal point). For example, a search on 0.0073 or .0073 will retrieve the same results. By default, a search is performed on a specific parallax error value (e.g., equals). Use the pull-down menu to perform a search on a parallax error value that is greater than or is less than the arcsecond entered in the search box.
Click Submit Query to search or Reset to clear the search fields.
The Search Results page displays the following information in column format:
During the data entry process, stars were assigned a study type depending on the context of their description within each volume: Light curve, Orbit, Radial velocity, Relative parallax, Spectroscopic binary, or Other. This information of "instance" is displayed in the Page Images Available column.
The AO Number, Parallax and Parallax Error values are only displayed for the star type: Relative parallax.
To view the specific page image for the individual star, click on the link containing the volume and page number. Please refer to the help section on Navigating and Viewing the Page Images for more information.
To determine the context of the page image within the volume, note the page number and select the Table of Contents link. Then scroll down the page to locate the appropriate section based on the page number.
Helpful Search Tip
Volume 10 is the only volume that published the relative parallax values apart from the individudal plate recordings. When following the link to a page image in Volume 10 from the Search Results page, you will be taken to the individual plate measurements for that star. The relative parallax values for each star in Volume 10 are located on pages 5-16 in AO number order.
Printing Page Images
The Digital Research Library realizes that printing capabilities are limited at the moment. We appreciate your patience until we can provide printing options that will better facilitate your research.
The University Library System, the Digital Research Library, and the Allegheny Observatory at the University of Pittsburgh welcome the citation of the online version of the Publications of the Allegheny Observatory of the University of Pittsburgh in scholarly writings. Relevant information should include the author's name, article title, and publication information of the original work; the title of the project and electronic publication information; and the date of access and the electronic address (URL).
Example: Baker, Robert H. (1910). The Orbits of the Spectroscopic Components of 2 Lacertae, Publications of the Allegheny Observatory of the University of Pittsburgh, 1 (13). Parallax Project, Digital Research Library, University of Pittsburgh. July 17, 2002 (http://digital.library.pitt.edu/parallax/01acr9511s/)