Swift Trigger: 1310284

Presumed name: GRB 250504A

BAT	17^h 58^m 26.88^s, -40° 20′ 56.4″
position:	(269.612, -40.349 ± 180″)
XRT	17^h 58^m 28.06^s, -40° 21′ 58.4″
position:	(269.61691, -40.36622 ± 1.9″)
UVOT	No position available.
Galactic N_HI:	1.33×10²¹ cm^-2
Galactic E(B-V):	0.199 mag

Best RA:	17^h 58^m 28.06^s	= 269.61691 d
Best Dec:	-40° 21′ 58.4″	= -40.36622 d

Gal Lat:	-8.05
Gal Long:	351.44

Sun angle:	132.29°, 8.8 hr West

GCN Notices for this burst.

View this region in Aladin.

Observability of this burst for Swift.

Sun angle for this burst.

UVOT data

No UVOT images are currently available.

XRT SPER data

SPER results page for this trigger.

There are 6 SPER messages, and 1 objects have been found

- Object 1 - enhanced position.
- RA (J2000) : 17 58 28.08 (-40.36632)
- Dec (J2000): -40 21 58.8 ( -40.36578)
- Error (90%): 1.9
- Counts in Source: 442

See the SPER page for details of how this position was produced.

Known transients within 5′ of the GRB

Click on the offset to view the transient announcement.

Offset (′′)	RA	Dec	Date reported	Source	Misc	Query

Catalogue Searches. Searched 200′ around XRT position

Click on the distance to view the full details (not available for sources from the SSS catalogue). Click on the column headers to sort the table on that column (click again to invert sort order).

SIMBAD

	RA*	Dec*	SIMBAD name
72.1	269.6120	-40.3859	TYC 7890-946-1	B=12.17, G=11.978795, H=11.481, J=11.569, K=11.391, V=12.63
82.2	269.6439	-40.3564	Gaia DR3 4035548934885262336	G=18.246689
95.3	269.5933	-40.3468	Gaia DR3 4035549695089574528	G=19.583691
102.3	269.6542	-40.3656	Gaia DR3 4035548939174329984	G=19.411512
117.0	269.6574	-40.3766	TYC 7890-1114-1	B=12.97, G=12.295841, H=10.997, J=11.313, K=10.957, V=12.37
120.4	269.5742	-40.3737	Gaia DR3 4035548183260928128	G=19.965477
122.1	269.5882	-40.3921	OGLE BLG-DSCT-13730	I=17.432
137.2	269.6515	-40.3938	Gaia DR3 4035548629992383744	G=18.035582
151.7	269.5666	-40.3488	Gaia DR3 4035548419470903040	G=18.265974
172.7	269.6010	-40.4126	2MASS J17582424-4024455	G=12.496874, H=8.596, J=9.579, K=8.341

There are 16 SIMBAD objects within the position error. The full list is here.

* RA/Dec in equinox J2000

X-ray sources

	RA*	Dec*		Source table²	Observatory	Query

Queried the X-ray MASTER catalogue.

* RA/Dec in equinox J2000

¹Energy band for count-rate is mission specific.

Galaxies

	RA*	Dec*		Catalogue
3.1	269.6179	-40.3658	B2=17.0, R1=17.4, R2=18.1	USNO-B1
9.7	269.6150	-40.3639		NED
12.7	269.6171	-40.3697		NED
15.1	269.6150	-40.3623	B2=17.6, R1=18.5, R2=19.3	USNO-B1
17.6	269.6108	-40.3681		NED
18.4	269.6112	-40.3692		NED
18.7	269.6200	-40.3617		NED
19.1	269.6217	-40.3625		NED
19.4	269.6237	-40.3653		NED
19.5	269.6237	-40.3656		NED

Queried APM-N, SDSS, PSCz, SSS, NED, 2MASSX, USNO-B1.

There are 1047 galaxies within the position error. The full list is here.

* 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

Stars

	RA*	Dec*		Catalogue
9.7	269.6150	-40.3640	h=15.7, j=16.4, k=15.7	2MASS
12.7	269.6174	-40.3697	h=15.8, j=16.0, k=15.1	2MASS
12.8	269.6176	-40.3697	B2=17.0, R1=16.7, R2=17.4	USNO-B1
13.7	269.6151	-40.3627	B2=19.2, R1=21.4, R2=20.0	USNO-B1
14.0	269.6212	-40.3684	R1=17.7, R2=18.6	USNO-B1
15.2	269.6215	-40.3685	B2=16.8, R1=16.8, R2=17.6	USNO-B1
17.6	269.6110	-40.3681	h=15.4, j=16.3, k=14.9	2MASS
17.7	269.6111	-40.3683	I=15.9, R1=16.7, R2=16.9	USNO-B1
18.4	269.6113	-40.3690	h=15.2, j=16.2, k=15.2	2MASS
18.4	269.6217	-40.3626	B2=16.1, R1=15.9, R2=16.3	USNO-B1

Queried USNO-B1, SDSS, 2MASS.

There are 2085 stars within the position error. The full list is here.

* 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.