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	12.216	19 55 51.01872	-17 45 42.6132	0675-34570292	298.962578	-17.761837			20.5	18.0	1983.047
2	20.756	19 55 50.85480	-17 45 17.0712	0675-34570196	298.961895	-17.754742			19.5	18.1	1983.047
3	21.182	19 55 51.77736	-17 45 55.5228	0675-34570726	298.965739	-17.765423			19.1	17.4	1983.047

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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	21.092	19 55 51.74712	-17 45 55.4652	S30223229820	298.965613	-17.765407	1992.355	17.73	0.44			3	2.38	0.03

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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	12.314	19 55 51.02472	-17 45 42.8508	0722-1116563	298.962603	-17.761903	237	165	1980.4	0	0	4		19.30	21.50	20.09	18.15
2	21.023	19 55 50.83344	-17 45 16.9524	0722-1116561	298.961806	-17.754709	121	121	1967.2	0	0	4	20.87	19.34	20.81	19.13
3	21.221	19 55 51.76152	-17 45 55.5804	0722-1116571	298.965673	-17.765439	43	112	1974.9	0	0	5	20.37	17.86	20.22	17.88	16.79
4	24.076	19 55 52.91808	-17 45 18.5112	0722-1116581	298.970492	-17.755142	44	158	1979.6	0	0	3		19.66		20.15	18.16

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	12.314	19 55 51.024672	-17 45 42.85008	0722-1158347	..	298.9626028	-17.7619028	B	0.0	0.0	0.0	0.0	21.500	B			20.090	B
2	21.026	19 55 50.833344	-17 45 16.94988	0722-1158345	..	298.9618056	-17.7547083	B	0.0	0.0	0.0	0.0	20.810	B			19.130	B
3	21.221	19 55 51.761328	-17 45 55.58004	0722-1158355	.M	298.9656722	-17.7654389	B	0.0	0.0	0.0	0.0	20.220	B			17.880	B	15.369	14.564	14.558
4	24.076	19 55 52.918008	-17 45 18.51012	0722-1158365	.M	298.9704917	-17.7551417	B	0.0	0.0	0.0	0.0					20.150	B	16.996	16.010	15.855

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Full	_r arcsec	_RAJ2000 "h:m:s"	[****ClosingBrace(s)Inserted****]
">

%22h:m:s%22&%">\BegDIVclass='sort-down ' </A>string _DEJ2000
"d:m:s"GSC2.3

RAJ2000
degDEJ2000
degEpoch
yrFmag
magjmag
magVmag
magNmag
magClass

a
pixe

1 9.80619 55 51.71712-17 45 24.6528SA0Q022295298.965488-17.7568481987.71020.80      3 1.50 0.41 211.69019 55 51.00672-17 45 41.5908SA0Q009886298.962528-17.7615531992.35519.8221.68  18.593 2.38 0.56 318.39919 55 50.66616-17 45 22.5900SA0Q022307298.961109-17.7562751987.71020.72      3 1.44 0.37 421.01919 55 50.85552-17 45 16.7508SA0Q010018298.961898-17.7546531992.35519.5620.12    3 1.66 0.25 521.08919 55 51.74736-17 45 55.4616SA0Q009820298.965614-17.7654061992.35517.7319.94  16.913 2.38 0.03 624.40319 55 52.92312-17 45 18.1008SA0Q022328298.970513-17.7550281987.71020.1422.23  18.273 2.49 0.44 728.16319 55 50.84712-17 46 00.1200SA0Q022196298.961863-17.7667001987.71020.73      3 1.54 0.35 829.61519 55 49.86264-17 45 19.4796SA0Q022324298.957761-17.7554111987.71020.3222.30    3 1.85 0.24 %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	12.273	19 55 51.02520	-17 45 42.7968	298.962605	-17.761888	-1.2	-5.6				21.50	19.30		18.15	3	0
2	20.861	19 55 50.83656	-17 45 17.1180	298.961819	-17.754755	0.5	-12.9			20.87	20.81	19.34			3	0
3	21.189	19 55 51.76848	-17 45 55.5408	298.965702	-17.765428	-1.5	-10.1	15.370	14.559	20.37	20.22	17.86	17.88	16.79	6	0
4	24.457	19 55 52.92576	-17 45 18.0612	298.970524	-17.755017	-2.0	0.5	16.997	15.856			19.66		18.16	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 [****ClosingBrace(s)Inserted****]
">

pmRAx

%20

%22>%5cFONT SIZE=-1mas/yrpmDEx
mas/yr

Fmag
mag

Bjmag
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

121.16419 55 51.76826-17 45 55.5157XPM 144-1391416298.965701-17.765421 -3.88 -3.80 -4.56 -3.7517.73219.935  16.91015.370 0.05514.564 0.05914.559 0.097 51429834719.117.4 59516.38393000M %0a%0a%3cP%3e%0a%3cFONT%20SIZE=%27-1%27%3e%3cEM%3e%3cFONT%20COLOR=%27#0000FF%27>%3cB%3eNote:%20%0a%25%25%25%20Introduction%20to%20UCAC4%20VizieR%20page%0a%3cEM%3e%25Note:%20%0a%20%20see%20the%20UCAC4%20document,%20and%20the%0a%20%20the%20fix%20for%20high%20proper%20motion%20stars.%0a%20%20The%20UCAC%20home%20page%20is%20available%20at%0a%20%20http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/ucac.%0a%20%20%3cBR%3ePlease%20%3cB%3eacknowledge%20the%20usage%0a%20%20of%20the%20UCAC4%0a%0a%25%3cP%3e%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	UCAC4	RAJ2000 deg	DEJ2000 deg	ePos mas	f.mag mag	of	db	pmRA mas/yr	pmDE mas/yr	Jmag mag	Kmag mag	Bmag mag	Vmag mag	rmag mag	imag mag	H	A	b	h	Z	B	L	N	S
1	21.337	19 55 51.324936	-17 45 55.23228	362-191551	298.9638539	-17.7653423	63	14.785	8	14	-110.2	16.7							0	0	0	0	0	0	0	2	0

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