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	0.866	17 49 10.32672	+31 45 34.4520	1200-08669691	267.293028	+31.759570			19.9	18.8	1952.546

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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	0.705	17 49 10.33152	+31 45 34.6500	1217-0297800	267.293048	+31.759625	242	393	1972.0	0	0	4	20.51	19.21	20.24	19.97
2	7.122	17 49 10.60416	+31 45 41.5116	1217-0297804	267.294184	+31.761531	999	999	1971.0	0	0	2	20.51		21.07

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>	\BegDIVclass='sort-down ' </A>
dec 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	0.707	17 49 10.331328	+31 45 34.65000	1217-0302116	..	267.2930472	+31.7596250	B	0.0	0.0	0.0	0.0	20.240	B			19.970	B
2	7.120	17 49 10.603992	+31 45 41.51016	1217-0302120	..	267.2941833	+31.7615306	B	0.0	0.0	0.0	0.0	21.070	B

Note: This version of the GSC-II has no proper motions, but the limits on brightness which existed on GSC2.2 (F<18.5, B_j<19.5) were removed.

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	0.346	17 49 10.35792	+31 45 34.7868	N3GX016345	267.293158	+31.759663	1993.480	19.61	20.57			3	2.79	0.26

%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	0.629	17 49 10.33128	+31 45 34.8912	267.293047	+31.759692	4.9	2.1			20.51	20.24	19.21	19.97		4	0
[****ClosingBrace(s)Inserted****]
">

%3cEM%3e1&%3cFONT%20COLOR=%27#CD5B45%27>%200.629&%3cFONT%20COLOR=%27#CD5B45%27>17%2049%2010.33128&%3cFONT%20COLOR=%27#CD5B45%27>%2b31%2045%2034.8912&267.293047&%2b31.759692&%20%20%20%20%204.9&%20%20%20%20%202.1&%20&%20&20.51&20.24&19.21&19.97&%20&%204&%200%3cBR%3e">\Ahref='VizieR-5?-ref=VIZ664336617acbc&-out.add=.&-source=I/317/sample&PPMXL===5430979902817418635' class='full'2 5.43717 49 10.47048+31 45 40.3020267.293627+31.761195 -35.4 -99.1    20.5121.07       2 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	0.629	17 49 10.33127	+31 45 34.8910	267.293047	+31.759692	0.115	0.115	20.569	0.300	19.609	0.300	19.814	0.400	19.016	0.500	1972.0200	1972.0200	4.9	5.9	2.1	5.9

%0a%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"	RA_ICRS deg	DE_ICRS deg	rmag mag	pmRA mas/yr	e_ (...)	pmxRA [****ClosingBrace(s)Inserted****]
">

pmxRA

%22>%5cFONT SIZE=-1mas/yre_
(...)Chi2RA

pmGRA
mas/yrpmDE
mas/yre_
(...)pmxDE
mas/yre_
(...)Chi2DE

pmGDE
mas/yrNobs

Flag

PS1

Gaia

DR9+DR12

Sloan

2M

1 0.50317 49 10.3094650330+31 45 34.504244029267.29310304306+31.7596567284920.594597 44.977 40.582 44.977 40.582 1.82732e-02   25.998 28.704 25.998 28.704 6.53894e-01   3 0PS1Gaia DR9+DR12Sloan2M %0a%0a

Full	_r arcsec	_RAJ2000 "h:m:s"	_DEJ2000 "d:m:s"	GSC2	RA_ICRS deg	DE_ICRS deg	objID	Epoch yr	Class	Gmag mag	OMag mag	Bjmag mag	Fpgmag mag	Epgmag mag	Npgmag mag	Umag mag	Bmag mag	Vmag mag	umag mag	gmag mag	rmag mag	imag mag	zmag mag	ymag mag	Jmag mag	Hmag mag	Ksmag mag	Zmag mag	Ymag mag	W1mag mag	W2mag mag	W3mag mag	W4mag mag	FUVmag mag	NUVmag mag	a pix	e pix	PA pix
1	0.617	17 49 10.3354424613	+31 45 34.432741978	N3GX016345	267.29308618000	+31.75961934000	1101210116345	2011.101	3			20.569100	19.610000							21.041	20.727	20.424	20.191	19.6035						18.050	17.751	12.695	8.731			2.786	0.261	139.9
[****ClosingBrace(s)Inserted****]
1	0.617	17 49 10.3354424613	+31 45 34.432741978	N3GX016345	267.29308618000	+31.75961934000	1101210116345	2011.101	3			20.569100	19.610000							21.041	20.727	20.424	20.191	19.6035						18.050	17.751	12.695	8.731			2.786	0.261	139.9

%22>\EndTABLESORT

Note: