Information on Service 'PPMXL Catalog Cone Search'

[Use this service from your browser]

Further access options are discussed below

PPMXL is a catalog of positions, proper motions, 2MASS- and optical photometry of 900 million stars and galaxies, aiming to be complete down to about V=20 full-sky. It is the result of a re-reduction of USNO-B1 together with 2MASS to the ICRS as represented by PPMX.

For a list of all services and tables belonging to this service's resource, see Information on resource 'ppmxl/q'

Service Documentation

To query this data, you can use

You can retrieve also the whole data set as a gzipped text file from http://vo.ari.uni-heidelberg.de/ppmxl (39.4 GiB). The columns in the text file are in database order as documented in the table info in DB order with columns separated by vertical bars ("|").

David Tholen kindly provided code to convert this into a collection of files for easy consumption by FORTRAN programs.

Overview

You can access this service using:

This service is published as follows:

local means it is listed on our front page, ivo_managed means it has a record in the VO registry, gavo means it is within GAVO's service registry.

Input Fields

The following fields are available to provide input to the service (with some renderers, some of these fields may be unavailable):

NameTable Head DescriptionUnitUCD
DEC Delta (ICRS) Declination (ICRS decimal) deg pos.eq.dec
hscs_pos Position/Name Coordinates (as h m s, d m s or decimal degrees), or SIMBAD-resolvable object N/A N/A
hscs_sr Search radius Search radius in arcminutes N/A N/A
ipix Id Identifier (Q3C ipix of the USNO-B 1.0 object) N/A meta.id;meta.main
RA Alpha (ICRS) Right Ascension (ICRS decimal) deg pos.eq.ra
SR Search Radius Search radius deg N/A

Default Output Fields

The following fields are contained in the output by default. More fields may be available for selection; these would be given below in the VOTable output fields.

NameTable Head DescriptionUnitUCD
b1mag USNO mag (B1) B mag from USNO-B, first epoch Note 1 N/A phot.mag;em.opt.B
b2mag USNO mag (B2) B mag from USNO-B, second epoch Note 1 N/A phot.mag;em.opt.B
dej2000 Dec Declination J2000.0, epoch 2000.0 deg pos.eq.dec;meta.main
e_deepDE E_deepde Mean error in Dec at mean epoch deg stat.error;pos.eq.dec;meta.main
e_pmDE Err. PM(Dec) Mean error in pmDE deg/yr stat.error;pos.pm;pos.eq.dec
e_pmRA Err. PM(RA) Mean error in pmRA*cos(delta) deg/yr stat.error;pos.pm;pos.eq.ra
e_raepRA E_raepra Mean error in RA*cos(delta) at mean epoch deg stat.error;pos.eq.ra;meta.main
Hmag m_H H selected default magnitude from 2MASS mag phot.mag;em.IR.H
imag USNO mag (I) I mag from USNO-B Note 1 N/A phot.mag;em.opt.I
ipix Id Identifier (Q3C ipix of the USNO-B 1.0 object) N/A meta.id;meta.main
Jmag m_J J selected default magnitude from 2MASS mag phot.mag;em.IR.J
Kmag m_K_s K_s selected default magnitude from 2MASS mag phot.mag;em.IR.K
pmDE PM(Dec) Proper Motion in Dec deg/yr pos.pm;pos.eq.dec
pmRA PM(RA) Proper Motion in RA*cos(delta) deg/yr pos.pm;pos.eq.ra
r1mag USNO mag (R1) R mag from USNO-B, first epoch Note 1 N/A phot.mag;em.opt.R
r2mag USNO mag (R2) R mag from USNO-B, second epoch Note 1 N/A phot.mag;em.opt.R
raj2000 RA Right Ascension J2000.0, epoch 2000.0 deg pos.eq.ra;meta.main

VOTable Output Fields

The following fields are available in VOTable output. The verbosity level is a number intended to represent the relative importance of the field on a scale of 1 to 30. The services take a VERB argument. A field is included in the output if their verbosity level is less or equal VERB*10.

NameTable Head DescriptionUnitUCD Verb. Level
raj2000 RA Right Ascension J2000.0, epoch 2000.0 deg pos.eq.ra;meta.main 1
dej2000 Dec Declination J2000.0, epoch 2000.0 deg pos.eq.dec;meta.main 1
pmRA PM(RA) Proper Motion in RA*cos(delta) deg/yr pos.pm;pos.eq.ra 1
pmDE PM(Dec) Proper Motion in Dec deg/yr pos.pm;pos.eq.dec 1
ipix Id Identifier (Q3C ipix of the USNO-B 1.0 object) N/A meta.id;meta.main 5
e_raepRA E_raepra Mean error in RA*cos(delta) at mean epoch deg stat.error;pos.eq.ra;meta.main 15
e_deepDE E_deepde Mean error in Dec at mean epoch deg stat.error;pos.eq.dec;meta.main 15
e_pmRA Err. PM(RA) Mean error in pmRA*cos(delta) deg/yr stat.error;pos.pm;pos.eq.ra 15
e_pmDE Err. PM(Dec) Mean error in pmDE deg/yr stat.error;pos.pm;pos.eq.dec 15
Jmag m_J J selected default magnitude from 2MASS mag phot.mag;em.IR.J 15
Hmag m_H H selected default magnitude from 2MASS mag phot.mag;em.IR.H 15
Kmag m_K_s K_s selected default magnitude from 2MASS mag phot.mag;em.IR.K 15
nobs #obs Number of observations used Note 4 N/A meta.number;obs 20
e_Jmag Err(m_J) J total magnitude uncertainty mag stat.error;phot.mag;em.IR.J 20
b1mag USNO mag (B1) B mag from USNO-B, first epoch Note 1 N/A phot.mag;em.opt.B 25
b2mag USNO mag (B2) B mag from USNO-B, second epoch Note 1 N/A phot.mag;em.opt.B 25
imag USNO mag (I) I mag from USNO-B Note 1 N/A phot.mag;em.opt.I 25
r1mag USNO mag (R1) R mag from USNO-B, first epoch Note 1 N/A phot.mag;em.opt.R 25
r2mag USNO mag (R2) R mag from USNO-B, second epoch Note 1 N/A phot.mag;em.opt.R 25
epRA Epra Mean Epoch (RA) yr time.epoch;pos.eq.ra 25
epDE Epde Mean Epoch (Dec) yr time.epoch;pos.eq.dec 25
e_Hmag Err(m_H) H total magnitude uncertainty mag stat.error;phot.mag;em.IR.H 25
e_Kmag Err(m_K_s) K_s total magnitude uncertainty mag stat.error;phot.mag;em.IR.K 25
magSurveys USNO Mag src. Surveys the USNO-B magnitudes are taken from Note 2 N/A meta.code 28
flags Flags Flags Note 3 N/A meta.code 28

VOResource XML (that's something exclusively for VO nerds)

Note 1

Magnitudes from USNO-B should be used with care. Photometric calibration may be severely off for some plates.

For objects from PPMX (bit 1 set in flags), these magnitudes have a special meaning as per the following table:

PPMXL column PPMX column PPMX content
b1mag Cmag Catalogue magnitude from source
b2mag Bmag Johnson B magnitude
r1mag Rmag calc. Ru magnitude from source
r2mag N/A always None
imag Vmag Johnson V magnitude
Note 2

magSurveys is built by concatenating the digits assigned to the surveys for b1mag, b2mag, r1mag, r2mag, and imag (in this sequence). The digits are those of given in Note h to Table 3 in 2003AJ....125..984M, except we do not distinguish POSS-II N and SERC-I as a part of POSS-I-N (i.e., both 7 and 9 are 7 here).

From this field, you can also see which of the surveys contributing to USNO-B had positions for the object.

Note 3

The flags column contains a bitwise or of warnings and similar conditions. The bit's meaning is as follows:

bit 0:If set, one of the coordinates had an excessively large chisquare.
bit 1:Row is from PPMX. These objects are mostly Tycho stars that were masked out of USNO-B. For these, the USNO magnitudes (b1mag through imag) have special meanings. See the note on magnitudes.
bit 2:Row is from PPMX and replaces a single row from USNO-B. This is done when the astrometry from PPMX was better (in terms of error estimates) than the astrometry of the corresponding PPMXL object.
bit 3:Row replaces multiple USNO-B1.0 objects. When PPMX contains an object that has more than one counterpart in PPMX-L, all such counterparts are discarded on the assumption that they should have been matched in USNO-B1.0 or result from erroneous matches. For these rows, bit 1 is always 1.
Note 4

nobs may be NULL for stars coming from ARIHIP or Tycho-2 via PPMX (i.e., bit 1 is set in flags).