Swift Trigger: 361830;

Presumed name: GRB 090904A

BAT	06^h 43^m 31.68^s, +50° 12′ 21.6″
position:	(100.882, +50.206 ± 180″)
XRT	06^h 43^m 32.59^s, +50° 12′ 13.7″
position:	(100.8858, 50.2038 ± 2.3″)
UVOT	No position available.
Galactic N_HI:	0.00×10⁰ cm^-2
Galactic E(B-V):	0.099 mag

Best RA:	06^h 43^m 32.59^s	= 100.8858 d
Best Dec:	+50° 12′ 13.7″	= 50.2038 d

Gal Lat:
Gal Long:

Sun angle:	not found

Stars within 3.33 of XRT position

	RA*	Dec*		Catalogue
21.9	100.8834	50.1979	B1=21.1, B2=21.0, I=18.6, R1=19.1, R2=19.2	USNO-B1
23.8	100.8955	50.2016	B1=20.9, B2=20.5, I=19.0, R1=19.3, R2=19.7	USNO-B1
37.0	100.8701	50.2061	B1=20.4, B2=19.9, I=18.6, R1=18.8, R2=19.2	USNO-B1
38.2	100.8696	50.2060	B1=21.0, R1=18.6	USNO-B1
42.7	100.8768	50.1935	B1=20.9, R1=19.7	USNO-B1
44.1	100.8941	50.1927	B1=20.8, B2=20.7, I=17.8, R1=18.8, R2=18.8	USNO-B1
47.3	100.8685	50.2109	h=14.0, j=14.4, k=14.1	2MASS
47.3	100.8686	50.2109	B1=16.7, B2=16.4, I=15.0, R1=15.3, R2=15.3	USNO-B1
52.9	100.8748	50.1909	B1=20.0, B2=19.3, I=18.6, R1=19.5, R2=19.2	USNO-B1
59.4	100.8834	50.2202	B1=20.1, B2=19.7, I=19.0, R1=19.1, R2=19.2	USNO-B1
61.6	100.8923	50.2204	h=14.6, j=15.4, k=14.5	2MASS
62.0	100.8923	50.2205	B1=20.6, B2=19.4, I=16.5, R1=17.4, R2=17.5	USNO-B1
62.5	100.8631	50.1943	B1=17.9, B2=17.4, I=15.8, R1=16.6, R2=16.4	USNO-B1
62.8	100.8631	50.1942	h=14.8, j=15.4, k=14.8	2MASS
71.0	100.9106	50.1921	B1=20.5, B2=20.5, I=18.6, R1=18.9, R2=19.7	USNO-B1
72.5	100.8685	50.1869	B1=18.1, B2=17.9, I=17.3, R1=17.1, R2=17.1	USNO-B1
75.3	100.8979	50.1844	B2=20.7, I=17.8, R1=18.6, R2=18.9	USNO-B1
75.8	100.8979	50.1842	h=15.5, j=16.0, k=15.1	2MASS
76.2	100.9121	50.2166	h=13.5, j=13.8, k=13.5	2MASS
77.3	100.9076	50.1875	B1=16.5, B2=16.5, I=15.2, R1=15.9, R2=15.6	USNO-B1
77.6	100.9076	50.1874	h=14.5, j=14.9, k=14.5	2MASS
77.7	100.9119	50.2174	B1=14.5, B2=14.1, I=12.8, R1=13.7, R2=13.1	USNO-B1
78.2	100.9116	50.2179	h=12.7, j=13.0, k=12.6	2MASS
79.5	100.9167	50.1940	h=14.1, j=14.3, k=14.0	2MASS
79.6	100.8650	50.1861	B1=15.0, B2=14.7, I=13.4, R1=14.1, R2=13.6	USNO-B1
79.6	100.9168	50.1940	B1=16.2, B2=16.0, I=14.9, R1=15.5, R2=15.1	USNO-B1
80.0	100.8650	50.1860	h=12.5, j=12.7, k=12.4	2MASS
86.9	100.8893	50.1798	B1=17.3, B2=16.8, I=15.1, R1=15.7, R2=15.6	USNO-B1
87.1	100.8892	50.1797	h=14.0, j=14.5, k=13.9	2MASS
88.7	100.8985	50.2271	B1=20.9, B2=21.1, I=17.6, R1=19.0, R2=19.4	USNO-B1
89.0	100.8974	50.2274	R1=19.8, R2=19.6	USNO-B1
89.2	100.8988	50.2272	h=16.1, j=16.2, k=15.6	2MASS
89.8	100.8851	50.2287	B1=20.3, I=18.6, R1=19.0	USNO-B1
90.0	100.8717	50.1805	B1=20.8, B2=20.1, I=18.3, R1=18.6, R2=19.1	USNO-B1
93.2	100.8763	50.2290	h=15.5, j=15.9, k=15.3	2MASS
93.5	100.8763	50.2290	B1=21.0, B2=20.5, I=17.5, R1=18.4, R2=18.9	USNO-B1
94.3	100.8519	50.1891	B1=20.3, B2=19.8, I=16.0, R1=17.4, R2=17.5	USNO-B1
94.6	100.8518	50.1890	h=14.1, j=14.8, k=13.8	2MASS
95.5	100.9233	50.2151	h=14.9, j=15.1, k=14.8	2MASS
95.5	100.9232	50.2152	B1=16.7, B2=16.9, I=15.6, R1=16.4, R2=16.1	USNO-B1
96.0	100.9089	50.2260	h=12.8, j=13.2, k=12.8	2MASS
96.2	100.9089	50.2261	B1=15.8, B2=15.3, I=14.0, R1=14.7, R2=14.2	USNO-B1
96.8	100.8508	50.1889	B1=20.3, B2=21.5, R1=17.3	USNO-B1
98.1	100.8528	50.1866	B1=20.9, B2=21.0, R1=19.5, R2=20.1	USNO-B1
100.6	100.8783	50.1763	h=15.0, j=15.5, k=15.3	2MASS
100.7	100.8781	50.1763	B1=17.5, B2=16.9, I=15.3, R1=15.6, R2=15.9	USNO-B1
104.9	100.8764	50.1753	h=14.3, j=14.8, k=14.1	2MASS
105.8	100.8407	50.2092	B1=18.8, B2=18.3, I=17.2, R1=17.6, R2=17.4	USNO-B1
105.8	100.8407	50.2092	h=16.1, j=16.3, k=15.3	2MASS
106.7	100.9166	50.1817	B1=19.0, B2=18.2, I=16.5, R1=17.4, R2=17.3	USNO-B1
107.1	100.9166	50.1815	h=15.1, j=15.6, k=15.1	2MASS
107.7	100.8879	50.1739	B1=20.9, B2=20.8, I=18.3, R1=18.9, R2=19.3	USNO-B1
107.8	100.8391	50.2021	B1=20.0, R1=19.4	USNO-B1
108.5	100.9311	50.2121	h=13.5, j=14.0, k=13.4	2MASS
108.7	100.9311	50.2122	B1=17.2, B2=16.6, I=14.9, R1=15.6, R2=15.4	USNO-B1
119.8	100.9361	50.1955	B1=18.6, B2=18.1, I=17.6, R1=17.8, R2=17.6	USNO-B1
120.6	100.9349	50.2154	h=14.9, j=15.5, k=14.6	2MASS
121.0	100.9350	50.2156	B1=19.1, B2=18.2, I=16.3, R1=17.1, R2=17.1	USNO-B1
124.0	100.9242	50.1797	B1=17.2, B2=16.9, I=15.7, R1=16.0, R2=16.0	USNO-B1
124.0	100.9242	50.1797	h=14.7, j=15.1, k=14.8	2MASS
127.1	100.8500	50.2307	B1=20.9, R1=18.4	USNO-B1
128.1	100.8433	50.1809	I=18.8, R1=20.1, R2=20.2	USNO-B1
130.8	100.8561	50.1728	B1=17.6, B2=17.1, I=16.1, R1=16.7, R2=16.4	USNO-B1
131.0	100.8562	50.1728	h=15.1, j=15.5, k=15.0	2MASS
131.4	100.9084	50.2373	B1=20.7, B2=20.3, I=18.3, R1=18.9, R2=19.0	USNO-B1
131.5	100.9085	50.2373	h=15.8, j=16.4, k=15.7	2MASS
132.7	100.8282	50.2049	h=14.4, j=14.7, k=14.3	2MASS
132.8	100.8282	50.2050	B1=16.7, B2=16.4, I=15.2, R1=15.4, R2=15.6	USNO-B1
133.8	100.9439	50.2037	B1=19.5, B2=21.0, R1=13.0	USNO-B1
134.0	100.9438	50.2009	B1=14.2, B2=13.7, I=12.8, R1=13.4, R2=12.8	USNO-B1
134.1	100.9438	50.2008	h=11.6, j=11.8, k=11.5	2MASS
138.2	100.9055	50.2401	I=18.7, R1=19.5	USNO-B1
145.2	100.9128	50.1674	B1=19.9, B2=19.3, I=18.8, R1=19.0, R2=19.2	USNO-B1
147.2	100.8629	50.2420	B1=20.8, R2=20.7	USNO-B1
148.8	100.8607	50.1657	B1=20.8, R1=19.5	USNO-B1
151.8	100.8753	50.2454	B1=20.9, R1=19.1	USNO-B1
152.3	100.8591	50.1651	B1=20.1, R1=19.2	USNO-B1
153.0	100.8212	50.2137	B1=18.9, B2=18.6, I=17.8, R1=17.8, R2=18.0	USNO-B1
153.1	100.8206	50.1956	B2=21.1, I=18.6, R1=19.2, R2=19.9	USNO-B1
155.0	100.9510	50.2146	B1=20.6, B2=20.8, I=18.6, R1=18.9, R2=19.5	USNO-B1
155.5	100.8268	50.2248	B1=20.9, B2=20.7, I=18.4, R1=19.0, R2=19.1	USNO-B1
159.0	100.8345	50.2333	h=13.5, j=13.8, k=13.5	2MASS
159.1	100.8345	50.2334	B1=15.9, B2=15.6, I=14.5, R1=14.7, R2=14.7	USNO-B1
160.4	100.9462	50.2259	B1=19.8, B2=17.1, I=16.8, R1=17.6, R2=17.1	USNO-B1
161.8	100.9032	50.1603	B1=20.8, B2=19.9, I=17.1, R1=18.2, R2=18.2	USNO-B1
161.9	100.9032	50.1602	h=15.2, j=16.0, k=15.5	2MASS
162.5	100.8356	50.2355	B2=20.7, I=18.9, R1=15.1, R2=19.3	USNO-B1
164.7	100.8722	50.2487	h=15.8, j=16.5, k=16.2	2MASS
168.1	100.9415	50.2340	h=15.3, j=15.7, k=15.3	2MASS
168.7	100.9416	50.2341	B1=18.0, B2=17.5, I=16.3, R1=16.9, R2=16.5	USNO-B1
170.0	100.9591	50.2089	h=14.1, j=14.4, k=14.0	2MASS
170.3	100.9593	50.2090	B1=16.9, B2=16.4, I=15.0, R1=15.4, R2=15.4	USNO-B1
170.8	100.9524	50.2246	B1=20.7, R1=19.1	USNO-B1
171.0	100.9527	50.2244	h=15.4, j=16.1, k=15.3	2MASS
171.4	100.9529	50.2244	B1=20.7, B2=19.9, I=17.0, R1=18.6, R2=18.5	USNO-B1
171.9	100.8150	50.1887	B2=21.1, I=18.1, R1=19.6, R2=20.2	USNO-B1
172.3	100.9508	50.1801	B1=19.5, R1=18.4	USNO-B1
172.7	100.9301	50.2425	h=15.3, j=15.8, k=15.2	2MASS
173.0	100.8134	50.1911	B1=20.3, R1=18.7	USNO-B1
173.2	100.9303	50.2426	B2=21.1, I=17.6, R1=18.7, R2=18.8	USNO-B1
174.9	100.9592	50.1914	B1=20.7, B2=20.6, I=18.4, R1=19.2, R2=19.6	USNO-B1
175.0	100.9549	50.2240	B2=20.1, I=17.8, R1=19.1, R2=18.5	USNO-B1
175.8	100.8681	50.1563	B2=21.9, I=18.8, R1=20.2	USNO-B1
175.9	100.8296	50.2369	B1=21.0, B2=20.5, I=17.3, R1=18.1, R2=18.6	USNO-B1
175.9	100.8295	50.2368	h=15.2, j=16.0, k=15.3	2MASS
176.5	100.8357	50.2409	B1=20.8, I=18.8	USNO-B1
176.6	100.8165	50.1829	B1=18.8, B2=18.5, I=17.7, R1=18.0, R2=17.9	USNO-B1
176.7	100.9441	50.2357	h=14.3, j=14.7, k=14.0	2MASS
176.9	100.9441	50.2358	B1=17.4, B2=16.9, I=15.5, R1=16.1, R2=15.7	USNO-B1
177.8	100.9471	50.2338	B1=18.6, B2=18.2, I=17.8, R1=18.1, R2=18.0	USNO-B1
177.9	100.8367	50.2420	h=14.8, j=15.3, k=14.9	2MASS
178.0	100.8367	50.2420	B1=17.7, B2=17.1, I=15.6, R1=16.0, R2=16.0	USNO-B1
178.7	100.8173	50.2270	h=12.6, j=13.3, k=12.4	2MASS
178.7	100.8173	50.2271	B1=18.5, B2=17.6, I=14.5, R1=15.6, R2=15.4	USNO-B1
181.3	100.8083	50.2126	h=15.2, j=15.9, k=14.8	2MASS
181.4	100.8083	50.2128	B1=20.9, B2=20.1, I=17.1, R1=18.7, R2=18.6	USNO-B1
183.1	100.8142	50.1817	h=15.3, j=16.4, k=15.7	2MASS
184.2	100.8138	50.1815	B1=17.2, B2=17.2, I=15.6, R1=16.1, R2=16.6	USNO-B1
186.2	100.8119	50.2247	h=14.8, j=15.2, k=14.8	2MASS
186.4	100.8118	50.2248	B1=17.6, B2=17.2, I=15.8, R1=16.4, R2=16.2	USNO-B1
186.7	100.8462	50.2491	I=18.8, R1=19.4, R2=20.1	USNO-B1
187.0	100.9091	50.2535	h=14.8, j=15.5, k=14.6	2MASS
187.2	100.8130	50.1807	h=15.1, j=15.8, k=15.1	2MASS
187.3	100.9093	50.2536	B1=20.7, B2=20.4, I=17.1, R1=18.6, R2=18.7	USNO-B1
188.7	100.8040	50.2058	B1=20.8, B2=20.5, I=18.3, R1=19.0, R2=19.1	USNO-B1
189.4	100.8145	50.2300	R1=18.3, R2=19.1	USNO-B1
190.1	100.8141	50.2300	h=14.6, j=15.2, k=14.4	2MASS
190.2	100.8627	50.2545	B1=19.8, B2=19.2, I=18.4, R1=18.3, R2=18.9	USNO-B1
190.4	100.8141	50.2301	B2=20.9, I=16.6, R1=18.5, R2=19.2	USNO-B1
190.6	100.9466	50.1679	B2=20.2, I=17.7, R1=18.5, R2=18.9	USNO-B1
190.6	100.9573	50.1772	I=18.2, R1=19.3, R2=20.0	USNO-B1
190.8	100.9573	50.1771	h=15.7, j=16.0, k=15.2	2MASS
191.2	100.8805	50.2568	B1=20.8, B2=20.1, I=18.0, R1=18.7, R2=19.2	USNO-B1
191.2	100.9468	50.1678	h=15.7, j=16.4, k=16.2	2MASS
192.5	100.9122	50.2545	B1=20.5, B2=20.1, I=17.9, R1=18.8, R2=19.1	USNO-B1
192.7	100.8200	50.2368	h=15.8, j=16.1, k=15.4	2MASS
193.2	100.8146	50.2322	B1=20.8, R1=20.0	USNO-B1
195.1	100.9286	50.2506	h=15.7, j=16.3, k=15.2	2MASS
195.3	100.9287	50.2506	B1=20.4, B2=20.6, I=17.8, R1=18.6, R2=18.8	USNO-B1
197.4	100.8068	50.2250	h=15.2, j=16.3, k=15.5	2MASS
197.7	100.8065	50.2248	B1=19.7, B2=18.3, I=16.6, R1=17.2, R2=16.7	USNO-B1
198.3	100.9584	50.2333	B1=19.2, B2=18.9, I=18.1, R1=18.7, R2=18.6	USNO-B1
198.4	100.8060	50.2245	B1=20.4, B2=18.6, I=16.5, R1=18.2, R2=17.3	USNO-B1
198.5	100.8056	50.2240	h=15.5, j=16.5, k=15.3	2MASS
199.7	100.8019	50.1899	R1=19.4, R2=20.6	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.