The Million Quasars (Milliquas) catalogue, version 4.1a (22 November 2014)

MILLIQUAS v4.1a includes data up to 22 November 2014, including SDSS-DR10Q (Paris I. et al, 2014,A&A,563,54). 1,017,708 type-I objects are displayed, including 300763 QSOs from the literature (type I only), 25576 AGN (like quasars but extended, e.g., Seyferts), 1580 Bl Lacs, 622322 photometric quasars from SDSS-based NBCKDE and BOSS, and 67467 radio/X-ray associated QSO candidates. Radio and/or X-ray identifications are shown where applicable, plus, for the photometric and radio/X-ray associated candidates, the probability of each being a true quasar. The threshold for inclusion of candidates is 80% QSO-likelihood. Monthly updates are being made to Milliquas as part of the process of writing a paper for it.

Quick browse of (flat text) data here , and here is the ReadMe

Get the file (36Mb with references list) here in FITS or as  flat text .


The earlier Milliquas v3.9 includes candidates of 70%+ QSO-likelihood, so has a larger set of 1,262,723 objects. You can still get it (28 Mb) here


Stars & Galaxies, radio/X-ray associated -- 22 November 2014

Milliquas is extracted from a larger database which includes stars & galaxies associated to radio/X-ray detections at 80%+ confidence. The counts are 191485 known galaxies and candidate galaxies (80%+ confidence), 14274 known stars and candidate stars (80%+ confidence), and 104414 candidates of unclear classification, although most of them will be galaxies.

I have made tables for each of these in the same layout as Milliquas, plus a table of extra references (citations) for them, all in a 12 Mb zipped file here in FITS or as flat text .

Legend of object classifications: G=galaxy, g=LRG, H=starburst, L=LINER, M=group, N=NELG,S=star, W=WD, C=CV. The percentage column shows the confidence that the radio/X-ray detection is truly associated to this object.

VCV Optical Catalog -- 22 November 2014

MILLIQUAS uses the Véron-Cetty & Véron Quasar Catalog (VCV: 2010,A&A,518,10) as the authority for pre-2010 quasars; however, these needed to be converted to long names and their astrometry shifted to their true optical positions. In the process many of the VCV objects were found to be stars or galaxies, or duplicates, or not to exist. The counts are: 168,941 QSOs/AGN/BlLacs presented in VCV, of which 157,678 are found to be type I (or Bl Lacs) and thus used in Milliquas, 4654 are found to be type II, and 6609 are found not to be quasars.

The optical mapping of the VCV catalog is available as 4 tables equating to the four original VCV tables (table1=QSOs, t2=BlLacs, t3=AGN, t4=false objects), plus a ReadMe, all zipped up into a single file. Get it here

The Atlas of Radio/X-ray Associations (ARXA, 2010 PASA, 27, 283) is here.


Eric Flesch, last updated 22 November 2014