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	3.815	16 33 46.95744	+20 26 32.3232	1050-08004646	248.445656	+20.442312			16.5	17.0	1950.205
2	8.899	16 33 46.72080	+20 26 36.4812	1050-08004609	248.444670	+20.443467			12.4	11.6	1950.205

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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 mag	Mflag [****ClosingBrace(s)Inserted****]
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Mflag

%22> 1 9.36816 33 46.69272+20 26 36.7404EO0055-0011735248.444553+20.44353911.90   1 15.83 25.2 0.3512.95   1 14.36 27.8 1.05   %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	8.944	16 33 46.71744	+20 26 36.4956	N103033310913	248.444656	+20.443471	1991.434	11.97	0.41	13.32	0.41	3	10.35	0.34

%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	4.293	16 33 46.93416	+20 26 32.7408	1104-0278046	248.445559	+20.442428	583	500	1963.9	0	0	3	16.86	15.80		14.88
2	8.682	16 33 46.73808	+20 26 36.4308	1104-0278044	248.444742	+20.443453	163	33	1976.7	0	0	5	12.97	11.49	12.24	11.32	10.74
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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	4.295	16 33 46.933992	+20 26 32.74008	1104-0283190	..	248.4455583	+20.4424278	B	0.0	0.0	0.0	0.0	16.860	o			14.880	B
2	8.682	16 33 46.738008	+20 26 36.43008	1104-0283188	YM	248.4447417	+20.4434528	B	0.0	0.0	0.0	0.0	17.460	Y			11.320	B	15.047	14.551	13.951

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Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	CMC14	f_	RAICRS deg	DEICRS [****ClosingBrace(s)Inserted****]
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DEICRS

%20

%22>%5cFONT SIZE=-1degr'mag
mag

Nt

Jmag
mag

Hmag
mag

Ksmag
mag

1 7.25916 33 46.90968+20 26 36.6972163346.9+202636  248.445457+20.44352716.936 1       %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	8.944	16 33 46.71768	+20 26 36.4992	N3SV010913	248.444657	+20.443472	1991.434	11.97	13.32	14.12	12.27	3	10.35	0.34

%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	4.985	16 33 46.89720	+20 26 33.2304	248.445405	+20.442564	-7.5	5.6			16.86		15.80	14.88		3	0
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%3cEM%3e1&%3cFONT%20COLOR=%27#CD5B45%27>%204.985&%3cFONT%20COLOR=%27#CD5B45%27>16%2033%2046.89720&%3cFONT%20COLOR=%27#CD5B45%27>%2b20%2026%2033.2304&248.445405&%2b20.442564&%20%20%20%20-7.5&%20%20%20%20%205.6&%20&%20&16.86&%20&15.80&14.88&%20&%203&%200%3cBR%3e">\Ahref='VizieR-5?-ref=VIZ663c5abc389fdb&-out.add=.&-source=I/317/sample&PPMXL===5306844889776046164' class='full'2 8.58716 33 46.73952+20 26 36.3084248.444748+20.443419 2.0 -3.115.04713.95212.9712.2411.4911.3210.74 6 0 %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	0.211	16 33 47.19378	+20 26 30.5817	248.446641	+20.441828	0.074	0.070	20.099	0.202	21.640	0.230	20.625	0.180	21.180	0.195	2003.4700	2003.4700	0.0	0.0	0.0
2	8.567	16 33 46.74603	+20 26 36.3834	248.444775	+20.443440	0.014	0.014	13.318	0.300	11.974	0.300	15.221	0.080	14.245	0.110	2003.4700	2003.4700	2.0	3.6	-3.1	3.6

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