Data Release 12 (DR12) is the final data release of the SDSS-III, containing all SDSS observations through July 2014. It includes the complete dataset of the BOSS and APOGEE surveys, and also newly includes stellar radial velocity measurements from MARVELS.
DR12 directly follows DR11, which was an internal release only to the SDSS collaboration, as well as the prior public release, DR10. DR12 and other past data releases can be viewed below.
Accessing the Data
The SDSS offers several different online data access tools, each suited to a particular need:
- Science Archive Server
- Interactive spectra and image mosaics
- Browser-based access to the Catalog Archive Server (CAS) database, with resources for learning SQL and projects to teach science
- Flexible advanced SQL-based interface to the CAS, for all data releases (quick registration required)
- DR12 FITS
- Direct download access to DR12 FITS data files for experts
- Data Model
- Details of the SAS directory structure, file formats, and the contents of each file
Working with SDSS Data
If you use public SDSS data in your paper, please see our guide on how to cite the SDSS. We hope you find our resources useful!
If you have questions about working with SDSS data, please email our helpdesk.
About Data Release 12
The Scope of DR12 provides more detailed information about DR12 sky coverage, and includes a coverage check form that links directly to SDSS imaging and optical spectroscopy data.
The items in the menubar above contain the following information about DR12:
- What’s new?
- Explains the differences between DR12 and previous data releases.
- Describes what data are available in DR12, including sky coverage, data size, and resolution information.
- Data Access
- Shows how to get common types of SDSS data, and provides links to all SDSS data access tools. This is the best place to look for a quick start using SDSS data.
- Explains what imaging data DR12 contains. It also provides details on the SDSS imaging pipeline, the calibration process, and what quantities (including units) are available in imaging catalog data.
- Optical Spectra
- Explains what data are available from the SDSS’s two optical spectrographs (SDSS-I and BOSS), and provides details on associated data including target flags, redshifts, and classifications.
- Infrared Spectra
- Explains what data are available from the SDSS’s new APOGEE infrared spectrograph, and provides details on associated data including information on the spectra, targets, radial velocities, and determinations of stellar atmospheric parameters.
Algorithms lists some of the principal SDSS-III data processing algorithms, including target selection, and contains complete details on how the algorithms work.
- Is new!
- Provides download instructions and documentation for a variety of software tools for working with SDSS data.
- Contains a glossary, Frequently Asked Questions, and other resources to help you get started in using DR12.
- Provide step-by-step guides to common research and teaching tasks using SDSS data. This is a good place to look for guidance in doing your science with the SDSS.
Complete details about DR12 are documented on this site and in the Data Release 12 paper (Alam et al. 2015).