The 3 columns in color are computed by VizieR, and are not part of the original data.

Note: USNO-A2.0 contains 526,280,881 sources, and is based on a re-reduction of the Precision Measuring Machine (PMM) scans from POSS-I O and E plates (>=-18°) and SRC-J and ESO-R plates (<=-20°). USNO-A2.0 was created by Dave Monet () and collaborators at Flagstaff Station, U.S. Naval Observatory.
The major difference between USNO-A2.0 and its previous version USNO-A1.0 is that A1.0 used the Guide Star Catalog as its reference frame whereas A2.0 uses the ICRF as realized by the USNO ACT catalog (Urban et al. 1997). The VizieR search engine uses an on-line compressed version (3.6Gbytes) which was generated at CDS.

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	USNO-A2.0	RAJ2000 deg	DEJ2000 deg	ACTflag	Mflag	Bmag mag	Rmag mag	Epoch yr
1	0.453	03 31 57.13536	+21 28 32.5128	1050-00950032	052.988064	+21.475698			19.1	18.2	1951.914
2	1.059	03 31 57.06888	+21 28 31.7928	1050-00950027	052.987787	+21.475498			18.8	18.3	1951.911
3	1.233	03 31 57.17616	+21 28 30.9324	1050-00950036	052.988234	+21.475259			17.6	17.1	1951.911
4	2.831	03 31 57.21552	+21 28 29.4312	1050-00950040	052.988398	+21.474842			17.9	16.9	1951.914
5	8.773	03 31 57.36744	+21 28 23.8800	1050-00950059	052.989031	+21.473300			14.3	13.8	1951.911

%0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20The%20%3cB%3eGuide%20Star%20Catalog%20has%20been%20constructed%20to%20support%20the%20%0aoperational%20need%20of%20the%20Hubble%20Space%20Telescope.%0aIt%20contains%20over%2025%20million%20positions%20for%20about%2019%20million%0aobjects,%20of%20which%20more%20than%2015%20million%20are%20classified%20as%20stars.%0aThe%20version%20%3cB%3e1.2%20is%20a%20new%20astrometric%20reduction%20which%20results%20in%0aabsolute%20position%20errors%20about%200.3-0.4%20arcsec.%0a%28see%20GSC%20pages%20at%20URL%20http://www-gsss.stsci.edu/gsc/gsc.html%29%0a%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	GSC	RAJ2000 deg	DEJ2000 deg	PosErr arcsec	Pmag mag	e_ mag	n_	Class	Plate	Epoch yr
1	8.95	03 31 57.3144	+21 28 23.448	0124600231	052.98881	+21.47318	0.4	13.71	0.40	1	0	01GY	1982.877
2	9.30	03 31 57.3144	+21 28 23.088	0124600231	052.98881	+21.47308	0.3	13.42	0.40	1	0	009M	1983.036
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%3cEM%3e2&%3cFONT%20COLOR=%27#CD5B45%27>%209.30&%3cFONT%20COLOR=%27#CD5B45%27>03%2031%2057.3144&%3cFONT%20COLOR=%27#CD5B45%27>%2b21%2028%2023.088&0124600231&052.98881&%2b21.47308&%200.3&13.42&%200.40&%201&0&009M&1983.036%3cBR%3e">\Ahref='VizieR-5?-ref=VIZ66376dba10a016&-out.add=.&-source=I/254/out&GSC=0124600231' class='full'3 9.5703 31 57.4104+21 28 23.2680124600231052.98921+21.47313 0.413.21 0.40 1000FH1982.875 %0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20The%20%3cB%3eGSC-ACT%20%3cEM%3e%28or%20%3cB%3eGSC1.3%29%0ais%20a%20recalibration%20of%20the%20%3cB%3e<%25E%20I/220%7cGSC1.1>,%20the%20catalogue%20constructed%20%0ato%20support%20the%20operational%20need%20of%20the%20Hubble%20Space%20Telescope,%0awith%20the%20%3cB%3e<%25E%20I/246%7cACT>,%20the%20combination%20of%20the%20Astrographic%20Catalogue%0aand%20the%20%3cB%3e%3cEM%3eTycho%20catalogue%20derived%20from%20the%20%3cEM%3e<%25E%20I/239%7cHipparcos>%0amission;%20see%20http://www.projectpluto.com/gsc_act.htm%20for%20more%20details%0aabout%20this%20recalibration.%0a%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	GSC	RAJ2000 deg	DEJ2000 deg	PosErr arcsec	Pmag mag	e_ mag	n_	Class	Epoch yr
1	8.79	03 31 57.3576	+21 28 23.808	0124600231	052.98899	+21.47328	0.3	13.45	0.41	1	0	1983.036
2	9.14	03 31 57.3600	+21 28 23.448	0124600231	052.98900	+21.47318	0.4	13.73	0.40	1	0	1982.877
3	9.62	03 31 57.3960	+21 28 23.124	0124600231	052.98915	+21.47309	0.4	13.21	0.40	1	0	1982.875

%0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20%3cB%3e%3cFONT%20COLOR=%27#CD5B45%27>%20The%20current%20version%20includes%20only%20the%20North%20%28POSS-I%20plates%29%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	APM-ID	RAJ2000 deg	DEJ2000 deg	rmag mag	l_	rClass	rStel	rDiam arcsec	rEll	bmag mag	l_	bClass	bStel	bDiam arcsec	b-r [****ClosingBrace(s)Inserted****]
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b-r

%22>%5cFONT SIZE=-1magMflag

1 7.92203 31 57.33744+21 28 24.6324EO0441-0423518052.988906+21.47350912.64   1 7.88 17.6 0.2714.16   1 6.85 17.7 1.51   2 9.14003 31 57.30888+21 28 23.2320EO1460-0003271052.988787+21.47312014.14   1 7.09 17.5 0.3314.99   1 7.35 17.5 0.85   3 9.61603 31 57.43752+21 28 23.3832EO0444-0006096052.989323+21.47316213.88   1 4.12 17.7 0.2515.23  -1 -0.09 16.9 1.35   %0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20The%20construction%20of%20the%20%0a%3cB%3eGSC-II%20%0ais%20still%20in%20progress:%20this%0aversion%20has%20no%20proper%20motions,%20and%20the%20magnitude%20limits%20are%2018.5%20in%20F%20%28red%29%0aand%2019.5%20in%20J%20%28blue%29.%20The%20data%20are%20%3cB%3e%3cFONT%20COLOR=%27#0000CD%27>copyrighted,%20check%20%0athe%20%3cB%3edata%20use%20Policy.%0a%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	GSC2.2	RA(ICRS) deg	DE(ICRS) deg	Epoch yr	Rmag mag	e_ mag	Bjmag mag	e_ mag	Class	a pix	e
1	0.148	03 31 57.14760	+21 28 31.9440	N33113319505	052.988115	+21.475540	1995.678	16.27	0.41	17.52	0.42	3	5.30	0.13
2	9.265	03 31 57.36936	+21 28 23.3652	N3311331295	052.989039	+21.473157	1995.678	13.66	0.41	14.74	0.42	0	4.81	0.13

%0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20The%20%3cB%3eUSNO-B%20Catalog%20presents%20positions,%20proper%20motions,%20%0amagnitudes%20un%20blue,%20red%20and%20infrared,%20as%20well%20as%20star/galaxy%20estimators%0afor%201,045,175,762%20objects%20derived%20from%203,648,832,040%20separate%20observations.%0aThe%20data%20were%20taken%20from%20scans%20of%207,435%20Schmidt%20plates%0ataken%20from%20various%20sky%20surveys%20during%20the%20last%2050%20years.%3cBR%3e%0aUSNO-B1.0%20catalog%20was%20created%20by%20Dave%20Monet%20and%20collaborators%0aat%20http://www.nofs.navy.mil/data/fchpix/%20%3cBR%3e%0a%3cB%3e%3cFONT%20COLOR=%27#EE0000%27>%20Note%20that%20the%20star/galaxy%20estimators%20may%20be%20mixed%20up%0a%20in%20dense%20regions.%0a%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	USNO-B1.0	RAJ2000 deg	DEJ2000 deg	e_RAJ2000 mas	e_DEJ2000 mas	Epoch yr	pmRA mas/yr	pmDE mas/yr	Ndet	B1mag mag	R1mag mag	B2mag mag	R2mag mag	Imag mag
1	0.380	03 31 57.13200	+21 28 32.4228	1114-0042430	052.988050	+21.475673	311	15	1951.9	0	0	2	19.55	17.96
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%3cEM%3e1&%3cFONT%20COLOR=%27#CD5B45%27>%200.380&%3cFONT%20COLOR=%27#CD5B45%27>03%2031%2057.13200&%3cFONT%20COLOR=%27#CD5B45%27>%2b21%2028%2032.4228&1114-0042430&052.988050&%2b21.475673&311&%2015&1951.9&%20%20%20%20%200&%20%20%20%20%200&2&19.55&17.96&%20&%20&%20%3cBR%3e">\Ahref='VizieR-5?-ref=VIZ66376dba10a016&-out.add=.&-source=I/284/out&USNO-B1.0===1114-0042431&-out.orig=o' class='full'2 1.16503 31 57.16008+21 28 30.93241114-0042431052.988167+21.4752591281061977.7 0 0518.5316.8416.1714.9916.68 3 1.24403 31 57.05472+21 28 31.82161114-0042429052.987728+21.4755062691141951.9 0 0219.8818.47       4 2.89503 31 57.21144+21 28 29.34121114-0042432052.988381+21.4748171953741951.9 0 0218.2116.62       5 8.85503 31 57.35352+21 28 23.72161114-0042433052.988973+21.473256 52 471977.7 0 0514.8012.9414.7113.6812.37 %0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20More%20recent%20versions%20available:%20UCAC3%20%28I/315%29%20and%20UCAC4%20%28I/322%29;%20see%20also%20the%20UCAC%20home%20page%20at%20http://ad.usno.navy.mil/ucac/%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	2UCAC	RAJ2000 deg	e_ mas	DEJ2000 deg	e_ mas	UCmag mag	No	Nc	pmRA mas/yr	pmDE mas/yr	2Mkey	Jmag mag	Kmag mag
1	8.700	03 31 57.335376	+21 28 23.79900	39259598	052.9888974	40	+21.4732775	38	13.93	4	2	-16.1	8.2	117033734	12.800	12.421

%0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20The%20Naval%20Observatory%20Merged%20Astrometric%20Dataset%20%28NOMAD%29%20contains%0aastrometric%20and%20photometric%20data%20for%20over%201%20billion%20stars%20derived%20from%0athe%20Hipparcos%20%28I/239%29,%20Tycho-2%20%28I/259%29,%20UCAC2%20%28I/289%29,%20and%20USNO-B1.0%0a%28I/284%29%20catalogs%20for%20astrometry%20and%20optical%20photometry,%20supplemented%0aby%202MASS%20%28II/246%29%20near-infrared%20photometry.%3cBR%3e%0a%3cFONT%20SIZE=%27-1%27%3eAn%20efficient%20remote%20query%20program%20%3cB%3efindnomad1%20is%0aavailable%20in%20the%20cdsclient%20%0apackage,%20for%20Unix/Linux%20platforms%0a%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	NOMAD1	YM	RAJ2000 deg	DEJ2000 deg	r	pmRA mas/yr	e_ (...)	pmDE mas/yr	e_ (...)	Bmag mag	r_	Vmag mag	r_	Rmag mag	r_	Jmag [****ClosingBrace(s)Inserted****]
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Jmag

%20

%22>%5cFONT SIZE=-1magHmag
mag

Kmag
mag

R

1 0.37703 31 57.132000+21 28 32.419921114-0045054..052.9880500+21.4756722B 0.0 0.0 0.0 0.019.550o    17.960e         2 1.16703 31 57.160008+21 28 30.929881114-0045055..052.9881667+21.4752583B 0.0 0.0 0.0 0.016.170B    14.990B         3 1.24503 31 57.054672+21 28 31.820161114-0045053..052.9877278+21.4755056B 0.0 0.0 0.0 0.019.880o    18.470e         4 2.89603 31 57.211344+21 28 29.340121114-0045056..052.9883806+21.4748167B 0.0 0.0 0.0 0.018.210o    16.620e         5 8.70003 31 57.335400+21 28 23.799001114-0045057YM052.9888975+21.4732775C -16.0 6.0 8.2 5.914.320Y13.740Y13.680B12.80012.43512.421   %0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20Zone%20-30/%2b50deg%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	CMC14	f_	RAICRS deg	DEICRS deg	r'mag mag	Nt	Jmag mag	Hmag mag	Ksmag mag
1	9.013	03 31 57.35088	+21 28 23.5416	033157.3+212823		052.988962	+21.473206	13.977	2

%0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20This%20version%20of%20the%20%0a%3cB%3eGSC-II%0ahas%20no%20proper%20motions,%20but%20the%20limits%20on%20brightness%20which%20existed%20on%0a%20%28F<18.5,%20B_j<19.5%29%20were%20removed.%0a%25The%20data%20are%20%3cB%3e%3cFONT%20COLOR=%27#0000CD%27>copyrighted,%20check%0a%25the%20%3cB%3edata%20use%20Policy.%0a%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	GSC2.3	RAJ2000 deg	DEJ2000 deg	Epoch yr	Fmag mag	jmag mag	Vmag mag	Nmag mag	Class	a pix	e
1	0.145	03 31 57.14760	+21 28 31.9476	NC59009505	052.988115	+21.475541	1995.678	16.27	17.52	18.93		3	5.30	0.13
2	9.266	03 31 57.36960	+21 28 23.3652	NC59000295	052.989040	+21.473157	1995.678	13.66	14.74	13.46	12.99	0	4.81	0.13

%0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20%20The%20limiting%20magnitude%20is%20about%2015.2%20in%20the%20GSC%20photometric%20system.%3cP%3e%0a