The million quasars (Milliquas) catalogue, version 4.0 (2014)

MILLIQUAS v4.0c includes data up to 5 August 2014, including SDSS-DR10Q (Paris I. et al, 2014,A&A,563,54). 1,022,360 objects are displayed, including 309480 QSOs from the literature (type I only), 21667 AGN (ie, Seyferts for which the integrated disk outshines the core), 1578 Bl Lacs, 622474 photometric quasars from SDSS-based NBCKDE and BOSS, and 67161 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 now raised to 80% QSO-likelihood, up from 70% before -- thus, v4.0 has about 240,000 less objects than v3.9, but there is a higher confidence of use.

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

Get the file (29 Mb zipped, has ReadMe & references list) here in FITS or as  flat text .


The previous version v3.9 has 1,262,723 objects including candidates of 70%+ QSO-likelihood. You can still get it (28 Mb, has ReadMe) here


Stars & Galaxies, radio/X-ray associated -- 30 August 2014

Milliquas is extracted from a larger database which includes stars & galaxies associated to radio/X-ray detections at 80%+ confidence. The counts are 192612 known galaxies and candidate galaxies (80%+ confidence), 14108 known stars and candidate stars (80%+ confidence), and 108682 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 an 11 Mb zipped file here in FITS or as flat text .

Legend of object classifications: G=galaxy, g=LRG, H=starburst, K=type 2 Seyfert/QSO, 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 -- 30 August 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 quasars were found to be stars or galaxies, or duplicates, or not to exist. The counts are: 168,939 QSOs/AGN/BlLacs presented in VCV, of which 158,830 are found to be type I and thus used in Milliquas, 4119 are found to be type II, and 5990 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 30 August 2014