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	2.470	22 06 16.59408	+51 32 00.5712	1350-15807326	331.569142	+51.533492			18.7	18.3	1952.710
2	8.586	22 06 15.94008	+51 31 55.9632	1350-15806873	331.566417	+51.532212			18.4	17.6	1952.710

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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	2.128	22 06 16.60728	+51 32 00.1572	N032121169267	331.569197	+51.533377	1989.754	18.36	0.42	19.36	0.43	3	2.39	0.16
2	8.986	22 06 15.92160	+51 31 55.3368	N032121169174	331.566340	+51.532038	1989.754	17.41	0.42	18.65	0.42	3	2.88	0.11

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>	\BegDIVclass='sort-down ' </A>
dec 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	2.452	22 06 16.58136	+51 32 00.3804	1415-0429511	331.569089	+51.533439	70	59	1975.2	0	0	5	19.67	17.81	19.17	18.40	17.93
2	8.919	22 06 15.91536	+51 31 55.6428	1415-0429499	331.566314	+51.532123	118	51	1975.2	0	0	5	19.27	17.12	18.66	17.29	17.14
3	9.572	22 06 17.74344	+51 31 55.2612	1415-0429535	331.573931	+51.532017	100	80	1977.3	0	0	3		18.58	20.04	19.16

Note: The Naval Observatory Merged Astrometric Dataset (NOMAD) contains astrometric and photometric data for over 1 billion stars derived from the Hipparcos (I/239), Tycho-2 (I/259), UCAC2 (I/289), and USNO-B1.0 (I/284) catalogs for astrometry and optical photometry, supplemented by 2MASS (II/246) near-infrared photometry.
An efficient remote query program findnomad1 is available in the cdsclient package, for Unix/Linux platforms

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 mag	Hmag mag	Kmag mag	R
1	2.452	22 06 16.581336	+51 32 00.38004	1415-0444728	..	331.5690889	+51.5334389	B	0.0	0.0	0.0	0.0	19.170	B			18.400	B
2	8.920	22 06 15.915336	+51 31 55.63992	1415-0444716	YM	331.5663139	+51.5321222	B	0.0	0.0	0.0	0.0	17.250	Y	17.340	Y	17.290	B	16.166	15.913	15.589
3	9.572	22 06 17.743344	+51 31 55.26012	1415-0444752	..	331.5739306	+51.5320167	B	0.0	0.0	0.0	0.0	20.040	B			19.160	B

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Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	GSC2.3 [****ClosingBrace(s)Inserted****]
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GSC2.3

%22>RAJ2000
degDEJ2000
degEpoch
yrFmag
magjmag
magVmag
magNmag
magClass

a
pixe

1 2.13022 06 16.60728+51 32 00.1608N2UD069267331.569197+51.5333781989.75418.3619.3618.9417.663 2.39 0.16 2 8.71722 06 17.68320+51 32 01.8600N2UD069306331.573680+51.5338501989.75419.6020.67    3 1.61 0.19 3 8.98622 06 15.92160+51 31 55.3368N2UD069174331.566340+51.5320381989.75417.4118.6517.9616.883 2.88 0.11 4 9.78022 06 17.76192+51 31 55.1352N2UD069138331.574008+51.5319821989.75419.4720.33    3 1.52 0.09 %0a%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	RAJ2000 deg	DEJ2000 deg	pmRA mas/yr	pmDE mas/yr	Jmag mag	Kmag mag	b1mag mag	b2mag mag	r1mag mag	r2mag mag	imag mag	No	fl
1	2.349	22 06 16.58904	+51 32 00.3012	331.569121	+51.533417	-0.1	1.2			19.67	19.17	17.81	18.40	17.93	5	0
2	8.912	22 06 15.92208	+51 31 55.5096	331.566342	+51.532086	-1.2	-0.8	16.166	15.589	19.27	18.66	17.12	17.29	17.14	6	0
3	9.651	22 06 17.75016	+51 31 55.2072	331.573959	+51.532002	-0.2	2.8				20.04	18.58	19.16		3	0

%0a%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	ID	RAICRS deg	DEICRS deg	pmRAp mas/yr	pmDEp mas/yr	pmRAx mas/yr	pmDEx mas/yr	Fmag [****ClosingBrace(s)Inserted****]
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Fmag

%20

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

Vmag
mag

Nmag
mag

Jmag
mag

e_
mag

Hmag
mag

e_
mag

Kmag
mag

e_
mag

2Mkey

Bmag
mag

Rmag
mag

Fld

dT
yr

fg

fs

M

1 8.84922 06 15.92978+51 31 55.5024XPM 283-0670537331.566374+51.532084 -1.36 -4.18 -1.11 -3.9517.40618.64617.96016.88016.166 0.11815.914 0.18015.589 0.264 73264850318.417.6 18946.99195100M %0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	RAJ2000 deg	DEJ2000 deg	e_RAJ2000 (...)	e_DEJ2000 arcsec	magBJ mag	e_ mag	magRF mag	e_ mag	magG mag	e_ mag	magGrvs mag	e_ mag	alphaEpoch yr	deltaEpoch yr	pmRA mas/yr	e_ (...)	pmDE mas/yr	e_ (...)
1	2.348	22 06 16.58907	+51 32 00.3007	331.569121	+51.533417	0.103	0.103	19.364	0.300	18.360	0.300	18.571	0.400	17.741	0.500	1975.2700	1975.2700	-0.1	5.6	1.2	5.6
2	8.714	22 06 17.68301	+51 32 01.8551	331.573679	+51.533849	0.400	0.400	20.672	0.300	19.601	0.300	19.820	0.400	18.943	0.500	1989.7500	1989.7500	0.0	0.0	0.0	0.0
3	8.912	22 06 15.92205	+51 31 55.5101	331.566342	+51.532086	0.090	0.090	18.646	0.300	17.406	0.300	17.641	0.400	16.647	0.500	1980.8800	1980.8800	-1.2	4.7	-0.8	4.7
4	9.651	22 06 17.75013	+51 31 55.2067	331.573959	+51.532002	0.133	0.133	20.326	0.300	19.468	0.300	19.658	0.400	18.932	0.500	1977.3600	1977.3600	-0.2	7.6	2.8	7.6

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