Swift Trigger: 380311;

Presumed name: GRB 091221

BAT	03^h 43^m 00.96^s, +23° 12′ 43.2″
position:	(55.754, 23.212 ± 180″)
XRT	03^h 43^m 11.59^s, +23° 14′ 25.1″
position:	(55.79829, 23.24031 ± 4.2″)
UVOT	No position available.
Galactic N_HI:	0.00×10⁰ cm^-2
Galactic E(B-V):	0.216 mag

Best RA:	03^h 43^m 11.59^s	= 55.79829 d
Best Dec:	+23° 14′ 25.1″	= 23.24031 d

Gal Lat:
Gal Long:

Sun angle:	not found

Stars within 3.33 of XRT position

	RA*	Dec*		Catalogue
10.3	55.8004	23.2382	B2=21.1, I=18.8, R1=19.4, R2=19.9	USNO-B1
33.3	55.8081	23.2423	B1=18.7, B2=18.0, I=17.0, R1=16.9, R2=17.1	USNO-B1
33.4	55.8082	23.2423	h=15.7, j=15.9, k=15.4	2MASS
36.7	55.7887	23.2353	I=18.9, R1=19.4	USNO-B1
41.8	55.7884	23.2330	B1=20.5, B2=20.4, I=18.4, R1=19.5, R2=19.1	USNO-B1
52.2	55.8087	23.2512	B2=20.6, I=18.4, R1=18.9, R2=19.5	USNO-B1
57.7	55.7864	23.2521	h=11.7, j=12.4, k=11.5	2MASS
58.0	55.7864	23.2521	B1=17.1, B2=16.1, I=13.0, R1=13.9, R2=14.2	USNO-B1
61.2	55.7939	23.2568	h=12.2, j=12.7, k=12.1	2MASS
61.4	55.7938	23.2569	B1=16.0, B2=15.3, I=13.2, R1=13.6, R2=14.1	USNO-B1
69.6	55.8091	23.2569	h=12.7, j=13.3, k=12.6	2MASS
69.8	55.8090	23.2570	B1=17.1, B2=16.3, I=14.1, R1=14.6, R2=14.9	USNO-B1
73.3	55.7892	23.2217	B2=21.9, R2=20.0	USNO-B1
74.7	55.8206	23.2434	I=18.7, R1=19.6, R2=18.5	USNO-B1
76.4	55.8211	23.2439	I=17.9, R1=18.5, R2=18.3	USNO-B1
78.0	55.8175	23.2278	B2=21.9, I=18.8, R1=19.7	USNO-B1
78.2	55.8209	23.2467	B1=13.6, B2=12.8, I=10.2, R1=11.0, R2=10.9	USNO-B1
78.3	55.8209	23.2466	h=8.5, j=9.1, k=8.3	2MASS
78.8	55.7890	23.2202	B1=19.5, B2=18.2, I=17.6, R1=17.5, R2=17.4	USNO-B1
79.2	55.7889	23.2201	h=15.9, j=16.3, k=15.6	2MASS
81.5	55.8208	23.2495	I=18.6, R2=18.4	USNO-B1
81.7	55.8160	23.2561	B1=20.8, B2=19.8, I=17.7, R1=19.0, R2=18.8	USNO-B1
81.9	55.7970	23.2176	B1=20.4, B2=18.9, I=18.1, R1=18.1, R2=18.5	USNO-B1
87.6	55.7875	23.2181	h=16.2, j=16.6, k=15.2	2MASS
88.2	55.8240	23.2467	I=18.2, R2=19.4	USNO-B1
92.0	55.7876	23.2168	B1=20.2, B2=19.0, I=16.6, R1=17.1, R2=17.4	USNO-B1
92.1	55.7877	23.2167	h=14.7, j=15.4, k=14.5	2MASS
93.0	55.8264	23.2407	h=15.9, j=16.4, k=15.3	2MASS
93.7	55.7713	23.2482	R1=19.7, R2=19.1	USNO-B1
94.1	55.8260	23.2463	B2=19.8, R2=19.6	USNO-B1
103.9	55.7681	23.2324	B2=21.9, I=19.3	USNO-B1
106.1	55.8304	23.2399	h=16.4, j=16.7, k=15.8	2MASS
114.7	55.8193	23.2150	B1=20.8, B2=19.9	USNO-B1
115.5	55.7794	23.2673	h=14.3, j=14.7, k=14.2	2MASS
115.8	55.7794	23.2674	B1=18.3, B2=17.0, I=15.3, R1=15.7, R2=15.8	USNO-B1
116.5	55.8196	23.2146	B2=19.9, I=15.6, R1=17.8, R2=17.9	USNO-B1
116.7	55.8196	23.2145	h=13.6, j=14.2, k=13.3	2MASS
122.9	55.7662	23.2232	B2=21.3, I=18.4, R2=20.0	USNO-B1
123.1	55.7662	23.2230	h=16.0, j=16.5, k=15.6	2MASS
126.5	55.7636	23.2256	h=15.3, j=15.8, k=15.0	2MASS
126.6	55.7635	23.2256	B1=20.5, B2=20.0, I=17.6, R1=18.3, R2=18.0	USNO-B1
127.6	55.7681	23.2183	B2=21.9, I=18.9, R2=19.5	USNO-B1
134.6	55.7641	23.2201	B2=21.9, I=19.1	USNO-B1
138.6	55.8289	23.2140	B1=18.6, B2=17.7, I=16.1, R1=16.4, R2=16.5	USNO-B1
138.8	55.8309	23.2646	B1=20.4, B2=19.0, I=17.4, R1=17.8, R2=17.5	USNO-B1
138.8	55.8310	23.2645	h=15.5, j=16.1, k=15.1	2MASS
138.9	55.8289	23.2139	h=15.0, j=15.3, k=15.1	2MASS
139.0	55.8027	23.2019	h=15.5, j=16.3, k=15.5	2MASS
139.0	55.8028	23.2019	B1=20.9, B2=19.9, I=17.9, R1=18.7, R2=18.2	USNO-B1
146.5	55.7889	23.2801	h=16.1, j=16.6, k=16.6	2MASS
146.8	55.7889	23.2802	B1=20.8, B2=19.4, I=18.3, R1=18.9, R2=18.5	USNO-B1
148.7	55.7563	23.2256	B2=21.5, I=18.9, R1=19.7, R2=19.6	USNO-B1
149.7	55.7558	23.2261	B1=20.6, B2=21.4	USNO-B1
149.9	55.8109	23.2003	B2=20.5, I=19.0, R1=19.7, R2=19.7	USNO-B1
149.9	55.8198	23.2037	B1=17.2, B2=19.2, I=17.8, R1=14.6, R2=18.1	USNO-B1
150.0	55.8107	23.2002	B2=21.2, R2=20.5	USNO-B1
150.4	55.7784	23.2779	h=15.3, j=15.6, k=14.8	2MASS
150.6	55.7783	23.2779	B1=19.0, B2=17.6, I=16.5, R1=16.9, R2=16.7	USNO-B1
151.9	55.8198	23.2030	B2=16.3, I=14.3, R2=15.0	USNO-B1
152.0	55.8198	23.2030	h=13.0, j=13.7, k=12.9	2MASS
155.0	55.7970	23.1973	B1=19.8, B2=18.6, I=16.8, R1=17.3, R2=17.2	USNO-B1
155.1	55.7971	23.1972	h=15.3, j=15.8, k=15.2	2MASS
159.5	55.7896	23.2839	B2=19.4, R2=21.0	USNO-B1
160.2	55.7859	23.2833	B2=20.5, R2=19.5	USNO-B1
160.5	55.7787	23.2811	h=14.2, j=14.8, k=14.1	2MASS
160.7	55.7787	23.2811	B1=18.8, B2=17.7, I=15.7, R1=16.2, R2=16.3	USNO-B1
165.8	55.8482	23.2362	B1=20.5, B2=19.4, I=17.3, R1=17.6, R2=17.6	USNO-B1
165.9	55.8482	23.2362	h=15.1, j=15.8, k=14.8	2MASS
167.1	55.7932	23.2865	B2=21.0, R1=19.9, R2=19.9	USNO-B1
167.3	55.8215	23.1990	B1=20.8, B2=20.5, I=18.6, R1=19.2, R2=19.6	USNO-B1
168.3	55.7719	23.2803	B1=20.7, B2=20.4, I=18.6, R1=19.6, R2=18.9	USNO-B1
172.5	55.8402	23.2688	h=11.0, j=11.3, k=10.9	2MASS
172.6	55.8402	23.2689	B1=14.1, B2=13.5, I=11.6, R1=12.2, R2=12.4	USNO-B1
174.0	55.8485	23.2259	B2=18.9, I=17.9, R2=17.9	USNO-B1
174.5	55.7727	23.2827	B1=21.1, B2=21.2, I=17.5	USNO-B1
178.4	55.8453	23.2645	h=16.2, j=16.8, k=15.7	2MASS
178.4	55.7444	23.2377	B2=20.5, I=18.8, R2=19.7	USNO-B1
179.1	55.8401	23.2719	B2=21.2, R2=20.4	USNO-B1
179.4	55.7864	23.1917	B2=21.3, I=18.4, R1=19.7, R2=19.8	USNO-B1
179.4	55.8497	23.2246	h=14.3, j=14.8, k=14.3	2MASS
179.8	55.7866	23.1915	h=16.0, j=17.1, k=16.0	2MASS
179.8	55.8518	23.2315	B2=19.2, R2=20.3	USNO-B1
180.3	55.7531	23.2123	B2=21.0, I=18.9, R1=19.5, R2=19.5	USNO-B1
181.5	55.8520	23.2301	B1=20.4, B2=19.7, R1=18.8, R2=19.3	USNO-B1
181.7	55.7444	23.2304	h=15.1, j=15.5, k=14.9	2MASS
181.8	55.8522	23.2303	B2=20.2, I=18.8, R1=18.6, R2=18.1	USNO-B1
182.0	55.7443	23.2304	B1=18.9, B2=17.8, I=16.4, R1=16.8, R2=16.8	USNO-B1
182.9	55.7608	23.2030	h=16.2, j=17.2, k=15.7	2MASS
183.2	55.7605	23.2031	B1=20.8, B2=21.1, I=18.5, R2=19.2	USNO-B1
184.3	55.7454	23.2244	B2=21.9, I=19.1	USNO-B1
184.4	55.7437	23.2298	B2=20.3, R2=19.7	USNO-B1
185.8	55.8522	23.2259	h=8.7, j=9.1, k=8.7	2MASS
189.3	55.7544	23.2740	B1=19.5, R2=21.1	USNO-B1
189.7	55.7525	23.2086	B2=21.0, R2=20.0	USNO-B1
191.0	55.8526	23.2224	B1=21.1, B2=17.7, I=18.4, R2=17.0	USNO-B1
191.5	55.7941	23.1873	B1=20.0, B2=18.6, I=17.5, R1=18.0, R2=17.9	USNO-B1
191.7	55.7942	23.1872	h=15.9, j=16.3, k=16.3	2MASS
193.1	55.8441	23.2071	B2=20.0, R1=19.9	USNO-B1
194.7	55.8551	23.2263	B2=20.4, I=18.5, R2=19.3	USNO-B1
195.0	55.7453	23.2640	R1=19.9, R2=20.1	USNO-B1
198.4	55.7400	23.2532	B1=21.1, R1=19.0, R2=19.6	USNO-B1

Queried USNO-B1, SDSS, 2MASS.

* RA/Dec in equinox J2000

Magnitudes depend on the catalogue. e.g. For Sloan, R is the Sloan r mag, not the Johnson R from APM, for example.