SkyServer: Table Descriptions

name type text

astromDR9 PHOTO Corrected astrometry based on DR9 results
As described in the Erratum to the Data Release 8 (DR8) paper (Aihara et al. 2011) the standard DR8 astrometry has some large errors, especially north of Dec = +41. This astrometry has been corrected for DR9. We provide this correction table for DR8 so that users have access to it within the same database. It contains the most relevant corrections to the photoObjAll table. Note that in photoObjAll there are other parameters that the astrometry changes for DR9 affect at a tiny level, but in this table we only publish the position corrections.

AtlasOutline PHOTO Contains a record describing each AtlasOutline object
The table contains the outlines of each object over a 4x4 pixel grid, and the bounding rectangle of the object within the frame.

DataConstants META The table stores the values of various enumerated and bitmask columnns.

DBColumns META Every column of every table has a description in this table

DBObjects META Every SkyServer database object has a one line description in this table

DBViewCols META The columns of each view are stored for the auto-documentation
* means that every column from the parent is propagated.

Dependency META Contains the detailed inventory of database objects
The objects are tracked by module

detectionIndex PHOTO Full list of all detections, with associated 'thing' assignment.
Each row in this table corresponds to a single catalog entry, or 'detection' in the SDSS imaging. For each one, this table lists a 'thingId', which is common among all detections of the same object in the catalog.

Diagnostics META This table stores a full diagnostic snapshot of the database.
The table contains the names of all the tables, views, stored procedures and user defined functions in the database. We leave out the Diagnostics itself, QueryResults and LoadEvents, etc these can be dynamically updated. We compute the row counts for each table and view. This is generated by running the stored procedure spMakeDiagnostics. The table was replicated upon the creation of the database into SiteDiagnostics.

Field PHOTO All the measured parameters and calibrations of a photometric field
A field is a 2048x1489 pixel section of a camera column. This table contains summary results of the photometric and calibration pipelines for each field.

FieldProfile PHOTO The mean PSF profile for the field as determined from bright stars.
For the profile radii, see the ProfileDefs table.

FileGroupMap META For 'big' databases, maps big tables to their own file groups
In big databases we only put core objects in the primary file group. Other objects are grouped into separate file groups. For really big files, the indices are put in even different groups. This table is truncated in the Task databases.

FIRST PHOTO SDSS objects that match to FIRST objects have their match parameters stored here

Frame PHOTO Contains JPEG images of fields at various zoom factors, and their astrometry.
The frame is the basic image unit. The table contains false color JPEG images of the fields, and their most relevant parameters, in particular the coefficients of the astrometric transformation, and position info. The images are stored at several zoom levels.

galSpecExtra SPECTRO Estimated physical parameters for all galaxies in the MPA-JHU spectroscopic catalogue.
These parameters give the probability distribution of each parameter in terms of its percent quantiles. These estimates are derived in the manner described in Brinchmann et al. 2004

galSpecIndx SPECTRO Index measurements of spectra from the MPA-JHU spectroscopic catalogue.
For each index, we give our estimate and error bar. Measurements performed as described in Brinchmann et al. 2004.

galSpecInfo SPECTRO General information for the MPA-JHU spectroscopic re-analysis
This table contains one entry per spectroscopic observation It may be joined with the other galSpec tables with the measurements, or to specObjAll, using specObjId. Numbers given here are for the version of data used by the MPA-JHU and may not be in perfect agreement with specObjAll.

galSpecLine SPECTRO Emission line measurements from MPA-JHU spectroscopic reanalysis
The table contains one entry per spectroscopic observation derived as described in Tremonti et al (2004) and Brinchmann et al (2004).

HalfSpace REGION The contraints for boundaries of the the different regions
Boundaries are represented as the equation of a 3D plane, intersecting the unit sphere. These intersections are great and small circles. THe representation is in terms of a 4-vector, (x,y,z,c), where (x,y,z) are the components of a 3D normal vector pointing along the normal of the plane into the half-scape inside our boundary, and c is the shift of the plane along the normal from the origin. Thus, c=0 constraints represent great circles. If c<0, the small circle contains more than half of the sky. See also the Region and RegionConvex tables

History META Contains the detailed history of schema changes
The changes are tracked by module

IndexMap META Table containing the definition of all indices
Contains all information necessary to build the indices including the list of fields. Drives both index creation and data validation.

Inventory META Contains the detailed inventory of database objects
The objects are tracked by module

LoadHistory META Tracks the loading history of the database
Binds the loadversion value to dates and Task names

Mask PHOTO Contains a record describing the each mask object

MaskedObject PHOTO Contains the objects inside a specific mask
This is a list of all masked objects. Each object may appear multiple times, if it is masked for multiple reasons.

Neighbors NEIGHBORS All PhotoObj pairs within 0.5 arcmins
SDSS objects within 0.5 arcmins and their match parameters stored here. Make sure to filter out unwanted PhotoObj, like secondaries.

PartitionMap META Shows the names of partitions/filegroups and their relative sizes

PhotoObjAll PHOTO The full photometric catalog quantities for SDSS imaging.
This table contains one entry per detection, with the associated photometric parameters measured by PHOTO, and astrometrically and photometrically calibrated.
The table has the following views:

PhotoObj: all primary and secondary objects; essentially this is the view you should use unless you want a specific type of object.
PhotoPrimary: all photo objects that are primary (the best version of the object).
Star: Primary objects that are classified as stars.
Galaxy: Primary objects that are classified as galaxies.
Sky:Primary objects which are sky samples.
Unknown:Primary objects which are no0ne of the above

PhotoSecondary: all photo objects that are secondary (secondary detections)
PhotoFamily: all photo objects which are neither primary nor secondary (blended)

The table has indices that cover the popular columns.

PhotoObjDR7 PHOTO Contains the spatial cross-match between DR8 photoobj and DR7 photoobj.
This is a unique match between a DR8 photoobj and a DR7 photoobj, and matches are restricted to the same run/camcol/field. The match radius is 1 arcsec, and within this radius preference is given to a photoprimary match over a secondary. If no primary match exists, the nearest secondary match is chosen. If more than one match of a given mode exists, the nearest one is chosen. The table contains the DR8 and DR7 objids and modes, the distance between them, and the DR7 phototag quantities.

PhotoPrimaryDR7 PHOTO Contains the spatial cross-match between DR8 primaries and DR7 primaries.
This is a unique match between a DR8 photoprimary and a DR7 photoprimary, and matches between different run/camcol/field are allowed. The match radius is 1 arcsec. The table contains the DR8 and DR7 objids, the distance between them and the DR7 phototag quantities.

PhotoProfile PHOTO The annulus-averaged flux profiles of SDSS photo objects
For the profile radii, see the ProfileDefs table.

Photoz PHOTO The photometrically estimated redshifts for all objects in the Galaxy view.
Estimation is based on a robust fit on spectroscopically observed objects with similar colors and inclination angle.
Please see the Photometric Redshifts entry in Algorithms for more information about this table.
NOTE: This table may be empty initially because the photoz values are computed in a separate calculation after the main data release.

PhotozRF PHOTO The photometrically estimated redshifts for all objects in the Galaxy view.
Estimates are based on the Random Forest technique.
Please see the Photometric Redshifts entry in Algorithms for more information about this table.
NOTE: This table may be empty initially because the photoz values are computed in a separate calculation after the main data release.

PhotozRFTemplateCoeff PHOTO Template coefficients for the PhotozRF table.

Please see the Photometric Redshifts entry in Algorithms for more information about this table.
NOTE: This table may be empty initially because the photoz values are computed in a separate calculation after the main data release.

PhotozTemplateCoeff PHOTO Template coefficients for the Photoz table.

Please see the Photometric Redshifts entry in Algorithms for more information about this table.
NOTE: This table may be empty initially because the photoz values are computed in a separate calculation after the main data release.

Plate2Target Which objects are in the coverage area of which plates?
This table has an entry for each case of a target from the sppTargets table having been targetable by a given plate. Can be joined with plateX on the PLATEID column, and with sppTargets on the OBJID column. Some plates are included that were never observed; the PLATEID values for these will not match any entries in the plateX table.

PlateX SPECTRO Contains data from a given plate used for spectroscopic observations.
Each plate has 640 observed spectra. WE NEED TO SPECIFY WHERE INFORMATION COMES FROM

ProfileDefs META This table contains the radii for the Profiles table
Radii of boundaries of annuli, and number of pixels involved. aAnn is the area of the annulus, and aDisk is the area of the disk out to rOuter. The second column gives the first cell in the annulus, and the third indicates if the values in that annulus are derived from sinc shifting the image to center it on a pixel.
for details see http://www.astro.princeton.edu/~rhl/photomisc/profiles.ps

ProperMotions PHOTO Proper motions combining SDSS and recalibrated USNO-B astrometry.
These results are based on the technique described in Munn et al. 2004, AJ, 127, 3034

ProperMotionsDR9 PHOTO Corrected properMotions based on DR9 astrometry corrections.
As described in the Erratum to the Data Release 8 (DR8) paper (Aihara et al. 2011) the standard DR8 astrometry has some large errors, especially north of Dec = +41. This astrometry has been corrected for DR9, and here we provide the corrected proper motions corresponding to the objects in the ProperMotions table.

PubHistory META This table keeps the record of publishing into a table
this table only gets written into if this is a destination database. The table contains the names of the tables which were published into The table is wrttien by the publisher. It can be compared at the end to the contents of the Diagnostics table.

QueryResults META Store the results of performance tests here

RC3 PHOTO RC3 information for matches to SDSS photometry
All matches to the Third Reference Source Catalog within 6 arcsec are included. RC3 positions were updated with latest NED positions in 2008.

RecentQueries META Record the ipAddr and timestamps of the last n queries
Query log table to record last n query IPs and timestamps so that queries can be restricted to a certain number per minute per IP to prevent crawlers from hogging the system (see spExecuteSQL).

Region REGION Definition of the different regions
We have various boundaries in the survey, represented by equations of 3D planes, intersecting the unit sphere, describing great and small circles, respectively. This table stores the description of a region, the details are in the HalfSpace table.

CHUNK - the boundary of a given Chunk
STRIPE - the boundary of the whole stripe
STAVE - the unique boundary of the whole stripe, agrees with STRIPE for Southern stripes
PRIMARY - the primary region of a given CHUNK
SEGMENT - the idealized boundary of a segment
CAMCOL - the real boundary of a segment
PLATE - the boundary of a plate
TILE - the boundary of a circular tile
TIGEOM - the boundary of a Tiling Run, also includes inverse regions, which must be excluded
RUN - the union of the CAMCOLs making up a Run
WEDGE -- intersection of tiles as booleans.
TILEBOX -- intersection of TIGEOM respecting masks (these are positive convex TIGEOM)
SKYBOX -- intersection and union of TILEBOX to cover the sky with positive disjoin convex regions.
SECTORLETS -- intersection of Skyboxes with wedges. These are the areas that have targets.
SECTORS -- collects together all the sectorlets with the same covering (and excluded) tiles.
See also the RegionConvex and Halfspace tables

Region2Box Tracks the parentage which regions contribute to which boxes
For the sector computation, Region2Box tracks the parentage of which regions contribute to which boxs. TileRegions contribute to TileBoxes TileRegions and TileBoxes contribute to SkyBoxes Wedges and SkyBoxes contribute to Sectorlets Sectorlets contribute to Sectors

RegionArcs REGION Contains the arcs of a Region with their endpoints
An arc has two endpoints, specified via their equatorial coordinates, and the equation of the circle (x,y,z,c) of the arc. The arc is directed, the first point is the beginning, the second is the end. The arc belongs to a Region, a Convex and a patch. A patch is a contigous area of the sky. Within a patch the consecutive arcids represent a counterclockwise ordering of the vertices.

RegionPatch REGION Defines the attributes of the patches of a given region
Regions are the union of convex hulls and are defined in the Region table. Convexes are the intersection of halfspaces defined by the HalfSpace table. Each convex is then broken up into a set of Patches, with their own bounding circle. See also the Region table

Rmatrix REGION Contains various rotation matrices between spherical coordinate systems
The mode field is a 3-letter code indicating the transformation:
S2J - Survey-to-J2000

G2J - Galactic-to-J2000

J2G - J2000-to-Galactic

J2S - J2000-to-Survey

ROSAT PHOTO ROSAT All-Sky Survey information for matches to SDSS photometry
All matches of SDSS photometric catalog objects to ROSAT All Sky Survey. Both faint and bright sources used here (indicated as 'faint' or 'bright' in CAT column. See detailed documentation at http://www.xray.mpe.mpg.de/rosat/survey/rass-bsc/

Run Contains the basic parameters associated with a run
A run corresponds to a single drift scan.

RunShift META The table contains values of the various manual nu shifts for runs
In the early runs the telescope was sometimes not tracking correctly. The boundaries of some of the runs had thus to be shifted by a small amount, determined by hand. This table contains these manual corrections. These should be applied to the nu values derived for these runs. Only those runs are here, for which such a correction needs to be applied.

SDSSConstants META This table contains most relevant survey constants and their physical units

sdssImagingHalfSpaces REGION Half-spaces (caps) describing the SDSS imaging geometry
Each row in this table corresponds to a single polygon in the SDSS imaging data window function.

sdssPolygon2Field REGION Matched list of polygons and fields
Each row in this table corresponds to

sdssPolygons REGION Polygons describing SDSS imaging data window function
Each row in this table corresponds to a single polygon in the SDSS imaging data window function.

sdssTargetParam TILES Contains the parameters used for a version of the target selection code

sdssTileAll TILES Contains information about each individual tile on the sky.
Each 'tile' corresponds to an SDSS-I or -II spectroscopic observation. The tile covers a region of the 1.49 deg in radius, and corresponds to one or more observed plates. At the time the tile was created, all of the 'tiled target' categories (galaxies, quasars, and some very special categories of star) were assigned fibers; later other targets were assigned fibers on the plate.

sdssTiledTargetAll TILES Information on all targets run through tiling for SDSS-I and SDSS-II
This table is the full list of all targets that were run through the SDSS tiling routines. targetID refers to the SDSS object ID associated with the CAS DR7.

sdssTilingGeometry TILES Information about boundary and mask regions in SDSS-I and SDSS-II
This table contains both tiling boundary and mask information.

sdssTilingInfo TILES Results of individual tiling runs for each tiled target
This table has entry for each time a target was input into the SDSS tiling routines. targetID refers to the SDSS object ID associated with the CAS DR7. To get target information, join this table with sdssTiledTargets on targetID.

sdssTilingRun TILES Contains basic information for a run of tiling Contains basic information for a run of tiling

Sector Stores the information about set of unique Sector regions
A Sector is defined as a distinct intersection of tiles and TilingGeometries, characterized by a unique combination of intersecting tiles and a list of tilingVersions. The sampling rate for any targets is unambgously defined by the number of tiles involved (nTiles) and the combination of targetVersion.

segueTargetAll SPECTRO SEGUE-1 and SEGUE-2 target selection run on all imaging data
This table gives the results for SEGUE target selection algorithms for the full photometric catalog. The target flags in these files are not the ones actually used for the SEGUE-1 and SEGUE-2 survey. Instead, they are derived from the final photometric data set from DR8. Only objects designated RUN_PRIMARY have target selection flags set.

SiteConstants META Table holding site specific constants

SiteDBs Table containing the list of DBs at this CAS site.
The SiteDBs table contains the name, short description and status of each db available for user access in this CAS server. This is used to auto-generate the list of available user databases on the SkyServer front page (at least for the collab and astro sites).

SiteDiagnostics META This table stores the full diagnostic snapshot after the last revision
The table contains the names of all the tables, views, stored procedures and user defined functions in the database. We leave out the Diagnostics itself, QueryResults and LoadEvents, these can be dynamically updated. This was generated from the Diagnostics table when the DB was created.

SpecDR7 SPECTRO Contains the spatial cross-match between DR8 SpecObjAll and DR7 primaries.
This is a unique match between a DR8 SpecObjAll and a DR7 photoprimary within 1 arcsec. DR7 PhotoTag columns and relevant DR7 ProperMotions are also included for convenience.

SpecObjAll SPECTRO Contains the measured parameters for a spectrum.
This is a base table containing ALL the spectroscopic information, including a lot of duplicate and bad data. Use the SpecObj view instead, which has the data properly filtered for cleanliness.

SpecPhotoAll FINISH The combined spectro and photo parameters of an object in SpecObjAll
This is a precomputed join between the PhotoObjAll and SpecObjAll tables. The photo attibutes included cover about the same as PhotoTag. The table also includes certain attributes from Tiles.

sppLines SPECTRO Contains outputs from the SEGUE Stellar Parameter Pipeline (SSPP).
Spectra for over 500,000 Galactic stars of all common spectral types are available with DR8. These Spectra were processed with a pipeline called the SEGUE Stellar Parameter Pipeline (SSPP, Lee et al. 2008) that computes line indices for a wide range of common features at the radial velocity of the star in question. Note that the line indices for TiO5, TiO8, CaH1, CaH2, and CaH3 are calculated following the prescription given by the Hammer program (Covey et al. 2007). UVCN and BLCN line indices are computed by he equations given in Smith & Norris (1982), and FeI_4 and FeI_5 indices by the recipe in Friel (1987). FeI_1, FeI_2, FeI_3, and SrII line indices are only computed from the local continuum. Thus, these line indices calculated from different methods report the same values for both the local continuum and the global continuum. These outputs are stored in this table, and indexed on the specObjID key index parameter for queries joining to other tables such as specobjall and photoobjall. See the Sample Queries in SkyServer for examples of such queries.

sppParams SPECTRO Contains outputs from the SEGUE Stellar Parameter Pipeline (SSPP).
Spectra for over 500,000 Galactic stars of all common spectral types are available with DR8. These Spectra were processed with a pipeline called the SEGUE Stellar Parameter Pipeline' (SSPP, Lee et al. 2008) that computes standard stellar atmospheric parameters such as [Fe/H], log g and Teff for each star by a variety of methods. These outputs are stored in this table, and indexed on the specObjID' key index parameter for queries joining to other tables such as specobjall and photoobjall. bestobjid is also added (and indexed?) Note that all values of -9999 indicate missing or no values. See the Sample Queries in SkyServer for examples of such queries.

sppTargets Derived quantities calculated by the SEGUE-2 target selection pipeline.
There are one of these files per plate. The file has one HDU. That HDU has one row for every object in photoObjAll that is classified as a star inside a 94.4 arcmin radius of the center of the plate. The data for each object are elements of the photoObjAll, specObjAll, sppPrams and propermotions tables taken unaltered from the CAS and derived quantities calculated by the segue-2 target selection code. Appended to the end are the two target selection bitmasks, segue2_target1 and segue2_target2, as set by the target selection code.

Columns from OBJID through PSFMAGERR_:
These are taken directly from photoObjAll

Columns from PLATEID through SEGUE2_TARGET2:
These are taken from the specObjAll and sppParams tables for any objects in this file that have matches in that specObjAll. For objects without matches in specObjAll, values are set to -9999. The names from SpecObjAll are unchanged.

Columns from MATCH through DIST20:
These are taken from the propermotions table, the USNOB proper motions as recalibrated with the SDSS by Jeff Munn. For objects without matches in the ProperMotions table, values are set to -9999. The names are unchanged from the propermotions table.

Columns from uMAG0 through VTOT_GALRADREST:
These are the derived quanitites calculated by the procedure calderivedquantities in derivedquant.pro in the segue-2 target selection code. With the addition of these, this file contains all the quanitites that the selection code operates on when choosing targets.

Columns MG_TOHV through V1SIGMAERR_TOHV:
These were added for the November 2008 drilling run and after. The earlier files will be retrofit (eventually).

StripeDefs PHOTO This table contains the definitions of the survey layout as planned
The lower and upper limits of the actual stripes may differ from these values. The actual numbers are found in the Segment and Chunk tables.

Target TILES Keeps track of objects chosen by target selection and need to be tiled.
Objects are added whenever target selection is run on a new chunk. Objects are also added when southern target selection is run. In the case where an object (meaning run,rerun,camcol,field,id) is targetted more than once, there will be only one row in Target for that object, but there will multiple entries for that Target in the TargetInfo table.

TargetInfo TILES Unique information for an object every time it is targetted

thingIndex PHOTO Full list of all 'things': unique objects in the SDSS imaging
Each row in this table corresponds to a single 'thing' observed by the SDSS imaging survey. By joining with the 'detectionIndex' table one can retrieve all of the observations of a particular thing.

TwoMass PHOTO 2MASS point-source catalog quantities for matches to SDSS photometry
This table contains one entry for each match between the SDSS photometric catalog (photoObjAll) and the 2MASS point-source catalog (PSC). See http://tdc-www.harvard.edu/catalogs/tmc.format.html for full documentation.

TwoMassXSC PHOTO 2MASS extended-source catalog quantities for matches to SDSS photometry
This table contains one entry for each match between the SDSS photometric catalog (photoObjAll) and the 2MASS extended-source catalog (XSC). See http://tdc-www.harvard.edu/catalogs/tmx.format.html for full documentation.

USNO PHOTO SDSS objects that match to USNO-B objects have their match parameters stored here
The source for this is the USNO-B1.0 catalog (Monet et al. 2003, AJ, 125, 984). This is simply the closest matching USNO-B1.0 object. See the ProperMotions table for proper motions after recalibrating USNO and SDSS astrometry. USNO-B contains five imaging surveys, two early epochs from POSS-I, and three later epochs from POSS-II, SERC and AAO.

Versions META Tracks the versioning history of the database
This is a log of all major changes that happened to the DB since its creation.

Zone ZONE Table to organize objects into declination zones
In order to speed up all-sky corss-correlations, this table organizes the PhotoObj into 0.5 arcmin zones, indexed by the zone number and ra.

zooConfidence Measures of classification confidence from Galaxy Zoo.
Only galaxies with spectra in DR7 are included (those in the zooSpec table). This information is identical to that in Galaxy Zoo 1 Table 4. The project is described in Lintott et al., 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2010. Anyone making use of the data should cite at least one of these papers in any resulting publications.

zooMirrorBias Results from the bias study using mirrored images from Galaxy Zoo
This information is identical to that in Galaxy Zoo 1 Table 5. The project is described in Lintott et al., 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2010. Anyone making use of the data should cite at least one of these papers in any resulting publications.

zooMonochromeBias Results from the bias study that introduced monochrome images in Galaxy Zoo.
This information is identical to that in Galaxy Zoo 1 Table 6. The project is described in Lintott et al., 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2010. Anyone making use of the data should cite at least one of these papers in any resulting publications.

zooNoSpec Morphology classifications of galaxies without spectra from Galaxy Zoo
This information is identical to that in Galaxy Zoo 1 Table 3. Some objects may have spectroscopic matches in DR8 (though they did not in DR7) It is not possible to estimate the bias in the sample, and so only the fraction of the vote in each of the six categories is given. The project is described in Lintott et al., 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2010. Anyone making use of the data should cite at least one of these papers in any resulting publications.

zooSpec Morphological classifications of spectroscopic galaxies from Galaxy Zoo
This information is identical to that in Galaxy Zoo 1 Table 2. This table includes galaxies with spectra in SDSS Data Release 7. The fraction of the vote in each of the six categories is given, along with debiased votes in elliptical and spiral categories and flags identifying systems as classified as spiral, elliptical or uncertain. The project is described in Lintott et al., 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2010. Anyone making use of the data should cite at least one of these papers in any resulting publications.

zooVotes Vote breakdown in Galaxy Zoo results.
Fraction of votes in each of the six categories, combining results from the main and bias studies. This information is identical to that in Galaxy Zoo 1 Table 7. The project is described in Lintott et al., 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2010. Anyone making use of the data should cite at least one of these papers in any resulting publications.

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