RA/DEC (2000)
06:57:45.530 +23:22:18.20
104.439708 +23.371722
Type
SN Ia
Redshift
0.256
Discovery ReportClassification Report
Related AstroNotes: 2026-1
Reporting Group
None
Discovering Data Source
None
Discovery Date
2025-12-22 03:04:00.000
TNS AT
Y
Public
Y
Discovery Mag
21.38
Filter
r-Sloan
Reporter/s
Alan M. Watson (UNAM), Diego López-Cámara (UNAM), Ny Avo Rakotondrainibe (LAM), Noémie Globus (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (NYUAD), Sarah Antier (IJCLAB), Rosa L. Becerra (UNAM), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Ramandeep Gill (UNAM), Nikos Mandarakas (LAM), Kin Ocelotl López (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Fredd Sánchez Álvarez (UNAM), Benjamin Schneider (LAM) and Antonio de Ugarte Postigo (LAM)
NEDSIMBADDECaLSPanSTARRS-1SkyMapperVizieRWISEDSSADS

Spectra

 ▌SN_2025alij - 2026-01-16 00:00:00 GTC / OSIRIS (None)z=
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   Binning factor: (rounded to nearest integer >1)
Mouse hovers at WL: 0 (rest),0 (observed)

Light curves

 ▌COLIBRI_DDRAGO_r
   
Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)
Spectra
 ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
22777 2026-01-16 00:00:00 GTC / OSIRIS A. Cabrera-Lavers(IAC), A. de Ugarte Postigo (LAM) A. Cabrera-Lavers(IAC), A. de Ugarte Postigo (LAM) None tns_2025alij_2026-01-16_GTC_OSIRIS_None.txt Object
Light Curves
Filter Tel / Inst Obs-date range JD Range Photometry
r-Sloan COLIBRI_DDRAGO 2025-12-22 03:04:15 - 2026-01-08 04:57:43 2461031.6279514 - 2461048.7067477 2
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
547581 2026-01-08 04:57:43 2461048.7067477 21.74 22.17 ABMag r-Sloan COLIBRI_DDRAGO 1800 S. Basa We re-observed on 2026-01-08 from 04:57 to 08:43 UTC and obtained 30 minutes of exposure using the DDRAGO two-channel wide-field imager on the COLIBRÍ telescope. The source is still present in images with a preliminary magnitude of r = 21.74 +/- 0.07. The data were reduced and coadded with the COLIBRÍ ASU pipeline. The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction.
547580 2025-12-22 03:04:15 2461031.6279514 21.38 23.71 ABMag r-Sloan COLIBRI_DDRAGO 10200 Alan M. Watson We initially observed from 2025-12-22 03:04 to 13:21 UTC and obtained 170 minutes of exposure in the r. The source was discovered at a preliminary magnitude of r = 21.38 +/- 0.01, using the DDRAGO two-channel wide-field imager on the COLIBRÍ telescope. The limiting magnitude of the image was r = 23.71 (10 sigma). The data were reduced and coadded with the COLIBRÍ ASU pipeline. The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction.
AT Reports
ID Time received (UT) Sender Reporter/s Reporting group Disc. Data Source RA DEC Discovery date (UT) Discovery Mag. Filter Related files AT Type Host name Internal name Assoc. Groups End prop. period Remarks ADS Bibcode Unreal Auto classification
286037 2026-01-08 21:56:15 Noémie Globus Alan M. Watson (UNAM),Diego López-Cámara (UNAM),Ny Avo Rakotondrainibe (LAM) et al. 06:57:45.530 +23:22:18.20 2025-12-22 03:04:00.000 21.38 r-Sloan Other mystery source We report the discovery of a new optical transient at RA = 06:57:45.53, Dec = +23:22:18.2 (J2000; uncertainty ~0.2"). This source was discovered during the follow-up of the Einstein Probe alert EP251221a, but is located well outside the WXT error box, so we consider them unrelated. Due to its brightness well beyond the archival images and its fading, we classify the object as an astronomical transient. We encourage follow-up at all wavelengths. We thank the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir and the COLIBRÍ and DDRAGO engineering teams. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico. 2026TNSTR..65....1W N
Classification Reports
ID Time received (UT) Sender Classifier/s Group Classification Redshift Spectra Related files Assoc. Groups End prop. period Remarks ADS Bibcode
22776 2026-01-16 12:11:15 Antonio Martin-Carrillo Antonio Martin-Carrillo (UCD), G. Corcoran (UCD), A. de Ugarte Postigo (LAM), B. Schneider (LAM), A. M. Watson (UNAM), N. Globus (UNAM), F. Agui Fernandez (CAHA), M. A. Aloy (UV), S. Basa (UAR Pytheas), A. Cabrera-Lavers(IAC), J. P. U. Fynbo (DAWN/NBI), L. Galbany (IEEC-CSIC), S. Geier (GTC), L. Izzo (INAF/OACN and DARK/NBI), G. Lombardi (GTC), D. López-Cámara (UNAM), D. B. Malesani (DAWN/NBI and Radboud), N. R. Tanvir (Univ. Leicester), C. C. Thoene (AbAO), N. A. Rakotondrainibe (LAM) None SN Ia 0.256 1 Classification based on template comparison using SNID. Excellent match with SN 1990N at +17 days. The redshift was obtained from emission lines seen in the spectrum. SNID also returned a consistent redshift. 2026TNSCR.190....1M
Spectra
ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
22777 2026-01-16 00:00:00 GTC / OSIRIS A. Cabrera-Lavers(IAC), A. de Ugarte Postigo (LAM) A. Cabrera-Lavers(IAC), A. de Ugarte Postigo (LAM) None tns_2025alij_2026-01-16_GTC_OSIRIS_None.txt Object

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