Tools for data access
DR7 data are distributed via the Catalog Archive
Server (CAS), an SQL database with fast search capabilities, and
the Data Archive Server (DAS), a collection of fits
images and tables containing the outputs of the imaging and
spectroscopic reduction pipelines. In addition, the SDSS collaboration
has created catalogs and other data products based on public survey
data that we link from our Value
Added Data Products page.
Catalog Archive Server (CAS) Search
|Catalog Archive Server (DR7 CAS)
||The Catalog Archive Server offers efficient search tools for
querying the imaging and spectro catalogs from SDSS, including
SEGUE and the stripe82 coadd. There are multiple entry URLs for
using the visual tools and query forms for the different databases:
Below, we just link to the Legacy versions of the search and
browse interface, but they exist analogously for all data sets. For
SQL queries, the different URLs just use different default
databases, but all others are selectable via the usual syntax.
|Spectro Query Server
||Search spectra by
position, or by spectral or photometric parameters. Retrieve survey
|Imaging Query Server
||Search photometry catalog by position or by photometric
parameters. Retrieve survey files.
||Upload plate,MJD,fiber list as part of a SQL query
||Find SDSS matches for a list of objects.
||Directly search the database using your own SQL queries (also see
skyserver help pages).
||Use this batch job server for direct SQL searches of the
database with generous timeout setting. Share result sets with your
collaborators. Access to BEST, TARGET, SEGUE verions of sky.
||Point and click on SDSS images.
||Generate jpeg finding charts from SDSS images.
||Get jpeg cutouts of SDSS imaging for object lists with link to
finding chart. Option to generate object list from SQL
In addition to using the web interfaces above, you can directly
connect to the database server to perform your own SQL queries using
||python script to submit
SQL queries from the command-line
||Submit SQL queries from an emacs buffer
Data Archive Server (DAS)
- images of the night sky ("corrected frames")
in fits and jpeg format
- calibrated object lists with photometric
parameters as fits binary tables
- reduced spectra and spectral parameters as fits
binary tables and ps/gif plots, both individually and
bundled for mass download.
Files and directories within the DAS are designated by survey
identifiers of the desired data:
run/rerun/camcol/field for imaging;
plate/MJD/fiberID for spectroscopy. The easiest way
to obtain this designation is by one of the query forms provided. See
the DAS quick
reference and the the DAS structure
and contents pages for what it contains.
Search & Retrieve
| DAS Coordinate search
||Find the imaging fields corresponding to a list of (list of) RA, Dec. coordinates
|DR7 DAS retrieval form
||Retrieve data for lists of object positions, or photometric or
spectroscopic SDSS ids (e.g. run/camcol/field or
plate/fiber) generated via one of the query forms above.
The coverage page explains runs,
access to Imaging / Spectro runs. For spectra, try: 2d_26 for
plate files, latest sprerun.
Recommended method for retrieving all Imaging or Spectro data.
Use your web browser or other http clients like
This page was last modified on $Date: 2008/12/19 19:39:24 $ (UT).