RA/DEC (2000)
11:44:33.115 -68:48:32.94
176.137979 -68.80915
Type
Nova
Redshift
Related AstroNotes: 2026-153
Reporting Group
ASAS-SN
Discovering Data Source
ASAS-SN
Discovery Date
2026-05-24 00:43:12.000
TNS AT
Y
Public
Y
Discovery Mag
9
Filter
g-Sloan
Reporter/s
K. Z. Stanek, for the ASAS-SN team

Spectra

 AT_2026noc - 2026-05-26 23:08:10 Other / Other (None)z=
 AT_2026noc - 2026-05-24 22:16:03 Lesedi / Mookodi (BlackGEM)z=
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Light curves

 ASASSN-2_Cassius_g
   
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
23853 2026-05-26 23:08:10 Other / Other 6000 2SPOT Olivier GARDE None tns_2026noc_2026-05-26.964_Other_Other_None.dat tns_2026noc_2026-05-26.964_Other_Other_None.fits Object taken with eShel spectrograph (R=11000) and a RC 12 inch telescope
23842 2026-05-24 22:16:03 Lesedi / Mookodi io_robot BlackGEM tns_2026noc_2026-05-24_22-16-03_Lesedi_Mookodi_BlackGEM.csv Object The spectrum covers the wavelength range ~4000–8000 Å and shows a blue, steeply declining pseudo-blackbody continuum with prominent Balmer emission lines at rest wavelengths: Hα (6563 Å), Hβ (4861 Å), and Hγ (4340 Å), indicating a redshift of z ≈ 0 and confirming the transient is Galactic in nature. A rich forest of blended Fe II multiplet emission features (multiplets 42, 49, 74) is clearly detected between ~4800–5200 Å, superimposed on the continuum. Based on the strong Balmer emission series at rest wavelengths, the presence of characteristic Fe II multiplet blends, and the hot blue continuum, we classify AT2026noc as a Galactic Classical Nova of the Fe II spectroscopic class (Williams et. al. 1992).
Light Curves
Filter Tel / Inst Obs-date range JD Range Photometry
g-Sloan ASASSN-2_Cassius 2026-05-10 03:21:36 - 2026-05-24 00:43:12 2461170.64 - 2461184.53 2
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
585139 2026-05-24 00:43:12 2461184.53 9 ABMag g-Sloan ASASSN-2_Cassius
585138 2026-05-10 03:21:36 2461170.64 16 ABMag g-Sloan ASASSN-2_Cassius [Last non detection]
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
305142 2026-05-24 20:58:53 Krzysztof Stanek K. Z. Stanek, for the ASAS-SN team ASAS-SN ASAS-SN 11:44:33.115 -68:48:32.94 2026-05-24 00:43:12.000 9 g-Sloan PNV ASASSN-26no ASAS-SN Bright Galactic Nova candidate (l/b=296.916/-6.72), present in multiple epochs 2026TNSTR2254....1S N
Classification Reports
ID Time received (UT) Sender Classifier/s Group Classification Redshift Spectra Related files Assoc. Groups End prop. period Remarks ADS Bibcode
23849 2026-05-27 16:42:33 Olivier GARDE Olivier GARDE (2SPOT) None Nova 1 classical Nova with p Cyg profil on Balmer's lines. 2026TNSCR2310....1G
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
23853 2026-05-26 23:08:10 Other / Other 6000 2SPOT Olivier GARDE None tns_2026noc_2026-05-26.964_Other_Other_None.dat tns_2026noc_2026-05-26.964_Other_Other_None.fits Object taken with eShel spectrograph (R=11000) and a RC 12 inch telescope
23838 2026-05-26 15:01:22 Moses Mlangeni M. Mlangeni (UCT/SAAO), S. de Wet (DTU), P. Groot (Radboud/UCT/SAAO), V. Moloi (UCT/SAAO), L. Booi (UCT/SAAO) BlackGEM Nova 1 BlackGEM We report the spectroscopic classification of AT2026noc obtained with the Lesedi 1.0-m telescope at the South African Astronomical Observatory (SAAO) equipped with the Mookodi spectrograph, Sutherland. A single spectrum was acquired on 2026-05-24 at 22:16:03 UTC with an exposure time of 600 s. The spectrum covers the wavelength range ~4000–8000 Å and shows a blue, steeply declining pseudo-blackbody continuum with prominent Balmer emission lines at rest wavelengths: Hα (6563 Å), Hβ (4861 Å), and Hγ (4340 Å), indicating a redshift of z ≈ 0 and confirming the transient is Galactic in nature. A rich forest of blended Fe II multiplet emission features (multiplets 42, 49, 74) is clearly detected between ~4800–5200 Å, superimposed on the continuum. 2026TNSCR2293....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
23842 2026-05-24 22:16:03 Lesedi / Mookodi io_robot BlackGEM tns_2026noc_2026-05-24_22-16-03_Lesedi_Mookodi_BlackGEM.csv Object The spectrum covers the wavelength range ~4000–8000 Å and shows a blue, steeply declining pseudo-blackbody continuum with prominent Balmer emission lines at rest wavelengths: Hα (6563 Å), Hβ (4861 Å), and Hγ (4340 Å), indicating a redshift of z ≈ 0 and confirming the transient is Galactic in nature. A rich forest of blended Fe II multiplet emission features (multiplets 42, 49, 74) is clearly detected between ~4800–5200 Å, superimposed on the continuum. Based on the strong Balmer emission series at rest wavelengths, the presence of characteristic Fe II multiplet blends, and the hot blue continuum, we classify AT2026noc as a Galactic Classical Nova of the Fe II spectroscopic class (Williams et. al. 1992).

Comments

TNS
System

Object coordinates updated

Object coordinates updated according to AT-report 305142 of Group ASAS-SN
Previous RA, DEC: 11:44:33.115, -68:48:32.94 (176.13798, -68.80915)
Updated RA, DEC: 11:44:33.115, -68:48:32.94 (176.137979, -68.80915)