2025mb | Transient Name Server

RA/DEC (2000)

00:34:16.878 -27:48:05.26

8.57032385767 -27.8014603714

Type

SN IIb

Redshift

0.005

Discovery Report Classification Report

Related AstroNotes: 2025-23

Reporting Group

ATLAS

Discovering Data Source

ATLAS

Discovery Date

2025-01-15 01:00:27.936

TNS AT

Public

Discovery Mag

18.011

Filter

orange-ATLAS

Reporter/s

J. Tonry, L. Denneau, H. Weiland, R. Siverd (IfA, University of Hawaii), N. Erasmus, W. Koorts (South African Astronomical Observatory), A. Jordan, V. Suc (UAI, Obstech), S. J. Smartt, K. W. Smith (Oxford/QUB), D. R. Young, M. Nicholl, M. Fulton, M. McCollum, T. Moore, J. Weston, X. Sheng, C. R. Angus, A. Wilson, A. Aamer, D. Magill (QUB), P. Ramsden (Birmingham/QUB), L. Shingles (GSI/QUB), S. Srivastav, J. H. Gillanders, H. Stevance, A. J. Cooper, F. Stoppa (Oxford), L. Rhodes (TSI/McGill), A. Rest (STScI), T.-W. Chen (NCU), C. Stubbs (Harvard), J. S. Sommer (LMU), B. P. Schmidt (ANU)

NED SIMBAD DECaLS PanSTARRS-1 SkyMapper VizieR WISE DSS ADS

Light curves

▌

GOTO-S_GOTO-3_L

▌

ATLAS-CHL_ATLAS-04_orange

▌

BG2_BlackGEM-Cam2_BG-q

▌

PS1_GPC1_w

Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)

Spectra

Select	ID	Obs-date (UT)	Tel / Inst	Exp-Time	Observer/s	Reducer/s	Group	Spectrum ascii file	Spec. Type	Remarks
	21709	2025-07-27 00:00:00	Keck1 / LRIS		Ravjit Kaur, Ryan Foley		UCSC	tns_2025mb_2025-07-27_Keck1_LRIS_UCSC.flm	Object
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks
	20187	2025-01-16 18:51:35	Lesedi / Mookodi	600	S. Potter, N. Erasmus, C. van Gend, H. Worters, S. Chandra, D. Cunnama, M. Hlakola, P. Rabe, R. Julie (all SAAO)	N. Erasmus, D. Cunnama, S. Potter (all SAAO)	SAAO IO	tns_2025mb_2025-01-16_18-51-35_Lesedi_Mookodi_SAAO_IO.flm	Object	The spectrum was taken with the SAAO's 1-m Lesedi robotic telescope with the Mookodi low-resolution spectrograph and imager [1] as part of the “IO” rapid follow-up program [2]. The spectrum was taken with the widest (4") slit width which resulted in a spectral resolution of R ~ 200 at 6000 Angstrom. [1] https://doi.org/10.1117/1.JATIS.10.2.025005 [2] https://doi.org/10.1117/12.3015250
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks The spectrum was taken with the SAAO's 1-m Lesedi robotic telescope with the Mookodi low-resolution spectrograph and imager [1] as part of the “IO” rapid follow-up program [2]. The spectrum was taken with the widest (4") slit width which resulted in a spectral resolution of R ~ 200 at 6000 Angstrom. [1] https://doi.org/10.1117/1.JATIS.10.2.025005 [2] https://doi.org/10.1117/12.3015250
	20172	2025-01-15 19:41:53	LT / SPRAT		Daniel Perley, Jacob Wise, K-Ryan Hinds, Aleksandra Bochenek, Zoe McGrath, Anna Ho	Jacob Wise	ZTF	tns_2025mb_2025-01-15_19-41-53.416_LT_SPRAT_ZTF.spec	Object
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks
	20179	2025-01-15 12:00:16	Lijiang-2.4m / YFOSC		Jujia Zhang		LiONS	tns_2025mb_2025-01-15_12-00-16.208_Lijiang-2.4m_YFOSC_LiONS.dat	Object
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks

Light Curves

Filter

Tel / Inst

Obs-date range

JD Range

Photometry

L-GOTO

GOTO-S_GOTO-3

2024-12-29 11:29:57 - 2025-06-05 17:57:31

2460673.979126 - 2460832.248265

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
493822	2025-06-05 17:57:31	2460832.248265	17.79	0.06		ABMag	L-GOTO	GOTO-S_GOTO-3	135
493821	2024-12-29 11:29:57	2460673.979126			20	ABMag	L-GOTO	GOTO-S_GOTO-3	180		[Last non detection]

orange-ATLAS

ATLAS-CHL_ATLAS-04

2025-01-14 02:01:30 - 2025-01-15 01:00:28

2460689.58438 - 2460690.54199

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
462262	2025-01-15 01:00:28	2460690.54199	18.011	0.138	18.59	ABMag	orange-ATLAS	ATLAS-CHL_ATLAS-04	30	Robot
462261	2025-01-14 02:01:30	2460689.58438			18.16	ABMag	orange-ATLAS	ATLAS-CHL_ATLAS-04	30	Robot	[Last non detection]

BG-q-BlackGem

BG2_BlackGEM-Cam2

2024-12-27 00:56:46 - 2025-05-19 10:10:28

2460671.5394213 - 2460814.9239352

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
492571	2025-05-19 10:10:28	2460814.9239352	17.43	0.05	19.88	ABMag	BG-q-BlackGem	BG2_BlackGEM-Cam2	60	robotic
492570	2024-12-27 00:56:46	2460671.5394213			20.88	ABMag	BG-q-BlackGem	BG2_BlackGEM-Cam2	60	robotic	[Last non detection]

w-P1

PS1_GPC1

2025-07-25 14:03:55 - 2025-07-25 14:03:55

2460882.08605 - 2460882.08605

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
505635	2025-07-25 14:03:55	2460882.08605	18.41	0.04	22	ABMag	w-P1	PS1_GPC1	45	Robot

AT Reports

Time received (UT)

Sender

Reporter/s

Reporting group

Disc. Data Source

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

264089

2025-07-28 00:22:54

PS1_Bot1

K. C. Chambers,T. de Boer,J. Fairlamb et al.

Pan-STARRS

00:34:16.878

-27:48:05.26

2025-07-25 14:03:54.720

18.41

w-P1

PSN

PS25flx

Pan-STARRS

257854

2025-06-05 19:25:45

GOTO_bot

D. O'Neill,K. Ackley,M. Dyer et al.

GOTO

00:34:16.886

-27:48:05.22

2025-06-05 17:57:30.528

17.79

L-GOTO

Other

GOTO25djf

GOTO

257235

2025-05-29 14:15:04

BlackGEM_Bot1

H. Tranin,F. Stoppa,D. Pieterse et al.

BlackGEM

00:34:16.874

-27:48:05.33

2025-05-19 10:10:28.000

17.43

BG-q-BlackGem

PSN

BGEM J003416.87-274805.3

BlackGEM

Related files

File	Comments	Last Modified (UT)	Modified By
tns_2025mb_atrep_257235_BlackGEM.pdf	Finding Chart	2025-05-29 14:15:06	BlackGEM_Bot1

241094

2025-01-15 09:33:31

ATLAS_Bot1

J. Tonry,L. Denneau,H. Weiland et al.

ATLAS

00:34:16.885

-27:48:05.26

2025-01-15 01:00:27.936

18.011

orange-ATLAS

PSN

ATLAS25akl

ATLAS

2025TNSTR.191....1T

Classification Reports

Time received (UT)

Sender

Classifier/s

Group

Classification

Redshift

Spectra

Related files

Assoc. Groups

End prop. period

Remarks

ADS Bibcode

21709

2025-08-05 23:19:58

Ravjit Kaur

Ravjit Kaur (UCSC), Ryan Foley (UCSC)

UCSC

SN IIb

0.005

UCSC

The spectrum has strong emission lines, including from H alpha, consistent with a Type II classification. We examined the earlier spectra using SNID (Blondin & Tonry, 2007, ApJ, 666, 1024), finding good matches with SNe IIb. We thus confirm the classification of Li et al., (2025, TNSCR 214).

2025TNSCR3092....1K

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
21709	2025-07-27 00:00:00	Keck1 / LRIS		Ravjit Kaur, Ryan Foley		UCSC	tns_2025mb_2025-07-27_Keck1_LRIS_UCSC.flm		Object

20187

2025-01-16 19:18:40

io robot

N. Erasmus (South African Astronomical Observatory, Stellenbosch University), D. Cunnama (South African Astronomical Observatory), S. Potter (South African Astronomical Observatory, University of Johannesburg)

SAAO IO

SN Ia

SAAO IO

Spectral template matching using NGSF (D. A. Howell et al. 2005 and S. Goldwasser et al. 2022) shows a reasonable match with a Type Ia supernova.

2025TNSCR.215....1E

Related files

File	Comments	Last Modified (UT)	Modified By
tns_2025mb_atrep_20187_SAAO_IO.pdf	The plot shows the best-fit from NGSF.	2025-01-16 19:18:40	io robot

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
20187	2025-01-16 18:51:35	Lesedi / Mookodi	600	S. Potter, N. Erasmus, C. van Gend, H. Worters, S. Chandra, D. Cunnama, M. Hlakola, P. Rabe, R. Julie (all SAAO)	N. Erasmus, D. Cunnama, S. Potter (all SAAO)	SAAO IO	tns_2025mb_2025-01-16_18-51-35_Lesedi_Mookodi_SAAO_IO.flm		Object			The spectrum was taken with the SAAO's 1-m Lesedi robotic telescope with the Mookodi low-resolution spectrograph and imager [1] as part of the “IO” rapid follow-up program [2]. The spectrum was taken with the widest (4") slit width which resulted in a spectral resolution of R ~ 200 at 6000 Angstrom. [1] https://doi.org/10.1117/1.JATIS.10.2.025005 [2] https://doi.org/10.1117/12.3015250

20179

2025-01-16 01:05:26

Liping Li

Liping Li, Qian Zhai, Jujia Zhang (YNAO); Xiaofeng Wang(THU)

LiONS

SN IIb

0.005

LiONS

The spectrum obtained by LJT is similar to that of an young SN IIb.

2025TNSCR.214....1L

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
20179	2025-01-15 12:00:16	Lijiang-2.4m / YFOSC		Jujia Zhang		LiONS	tns_2025mb_2025-01-15_12-00-16.208_Lijiang-2.4m_YFOSC_LiONS.dat		Object

20172

2025-01-15 20:32:01

Jacob Wise

Jacob Wise (LJMU), Daniel Perley (LJMU), K-Ryan Hinds (LJMU), Aleksandra Bochenek (LJMU), Zoe McGrath (LJMU), Anna Ho (Cornell)

ZTF

SN Ia

0.005294

ZTF

Spectrum is well-fit by template spectra of previously classified SN Ia approximately 14 days before maximum light. Redshift of z = 0.005294 ± 0.000005 for NGC 150 obtained from Springob et al. 2005. Classification performed using Next Generation Superfit (NGSF, Goldwasser et al. 2022).

2025TNSCR.200....1W

Related files

File	Comments	Last Modified (UT)	Modified By
tns_2025mb_atrep_20172_ZTF.pdf	NGSF fits	2025-01-15 20:32:01	Jacob Wise

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
20172	2025-01-15 19:41:53	LT / SPRAT		Daniel Perley, Jacob Wise, K-Ryan Hinds, Aleksandra Bochenek, Zoe McGrath, Anna Ho	Jacob Wise	ZTF	tns_2025mb_2025-01-15_19-41-53.416_LT_SPRAT_ZTF.spec		Object

Comments

Object coordinates updated

Object coordinates updated according to AT-report 264089 of Group Pan-STARRS
Previous RA, DEC: 00:34:16.874, -27:48:05.33 (8.570308, -27.801481)
Updated RA, DEC: 00:34:16.878, -27:48:05.26 (8.57032385767, -27.8014603714)

Object coordinates updated

Object coordinates updated according to AT-report 257235 of Group BlackGEM
Previous RA, DEC: 00:34:16.885, -27:48:05.26 (8.570355, -27.80146)
Updated RA, DEC: 00:34:16.874, -27:48:05.33 (8.570308, -27.801481)

SN 2025mb

Spectra

Light curves

Comments

Object coordinates updated

Object coordinates updated