TNS Astronomical Transient Report No. 264141 [ 2025TNSTR2954....1K ]
Date Received (UTC): 2025-07-28 09:50:48
Date made public:
Sender: N Paul Kuin
Reporting Group: Swift Discovery Data Source: Swift
N Paul Kuin report/s the discovery of a new astronomical transient.
IAU Designation: AT 2025smm
Coordinates (J2000): RA = 06:29:54.288 (97.4762) DEC = -37:13:55.56 (-37.2321)
Discovery date: 2025-07-28 00:34:55.000 (JD=2460884.5242477)
Remarks: discovered as a weak source during GW250727dc Swift followup possibly CBC GW afterglow
Photometry
Discovery (first detection):
Discovery date: 2025-07-28 00:34:55.000
Flux: 19.9 ABMag
Filter: U-Swift-UVOT
Instrument: UVOT-Imager
Telescope: UV/Optical Telescope on Swift
Remarks: new source found during GW250727dc Swift follow up, not present in any surveys checked, not a minor planet, unlikely to be an artifact, significance 3.8 sigma.
Last non-detection:
Archival info: DSS
Remarks: New candidate source is not in DSS
Details of the new object can be viewed here: https://www.wis-tns.org/object/2025smm
Date Received (UTC): 2025-07-28 09:50:48
Date made public:
Sender: N Paul Kuin
Reporting Group: Swift Discovery Data Source: Swift
N Paul Kuin report/s the discovery of a new astronomical transient.
IAU Designation: AT 2025smm
Coordinates (J2000): RA = 06:29:54.288 (97.4762) DEC = -37:13:55.56 (-37.2321)
Discovery date: 2025-07-28 00:34:55.000 (JD=2460884.5242477)
Remarks: discovered as a weak source during GW250727dc Swift followup possibly CBC GW afterglow
Photometry
Discovery (first detection):
Discovery date: 2025-07-28 00:34:55.000
Flux: 19.9 ABMag
Filter: U-Swift-UVOT
Instrument: UVOT-Imager
Telescope: UV/Optical Telescope on Swift
Remarks: new source found during GW250727dc Swift follow up, not present in any surveys checked, not a minor planet, unlikely to be an artifact, significance 3.8 sigma.
Last non-detection:
Archival info: DSS
Remarks: New candidate source is not in DSS
Details of the new object can be viewed here: https://www.wis-tns.org/object/2025smm