Reporting Group
MASTER
Discovering Data Source
MASTER
Discovery Date
2023-08-22 00:12:04.032
TNS AT
Y
Public
Y
Discovery Mag
18.2
Filter
Clear-
Reporter/s
Ya.Kechin, A.Sosnovsky, V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)
Light curves
▌Other_Other_R
▌Other_Other_Clear
Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)
Spectra
No Data
Light Curves
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 190908 | 2023-10-15 15:39:20 | Gianluca Masi | Gianluca Masi | 00:43:54.360 | +40:46:34.00 | 2023-08-10 21:50:24.000 | 18.9 | R-Cousins | AGN | On 15 Aug. 2023, during a regular survey work on the Messier 31 (NGC 224) field, performed with the 0.25m-f/4.5 robotic unit part of the Virtual Telescope Project facility in Manciano, Italy, we discovered a bright object on several unfiltered images, located at RA,DEC=00 43 54.36, +40 46 34.0 (J2000.0 astrometry from the discovery image). On 15.07 Aug. 2023 we estimated it at R=18.2 (R-mags for the reference stars from the Gaia DR2 catalogue). We have found the source by comparing the 15 Aug. images with 10.91 Aug. ones, taken via the same equipment. On the 10.91 Aug. images, the source was at R=18.9. We labelled this source as VTP J004354.36+404634.0 within our survey program. We queried Simbad at the mentioned coordinates, concluding it is most likely an optical counterpart to a nearby ( r < 1”) radio source NVSS J004354+404634. At the same position, Vizier reports a few entries for X-ray sources. SDSS (DR16) reports an optical source at two different epochs at the mentioned coordinates: 2002.7634: g=22.6 and r=22.5 (errors: 0.2 mags) 2002.7584: g=23.8 and r=23.4 (errors: 0.9 and 0.6 mags, respectively) Pan-STARRS DR1 reports an optical source, too: 11 July 2012: g=22.08 and r=21.24 (errors: 0.08 and 0.07 mags, respectively) On 22 Aug. 2023, the MASTER survey detected a mag. 18.2 (clear) object, reporting it as a probable nova in M31, with no follow-up: https://www.wis-tns.org/object/2023qhf The CRTS archival light curve shows evident optical variability in V-band between 2006 and 2013, never brighter than V=18.6 (with detection limit at about V=21). Our data, from 10 Aug. 2023 to 13 Oct. 2023 likely covers an unprecedented bright flare reaching R=17.6 on 19.82 Aug. 2023 (UT). The source has been brighter than R=19.0 for more than 60 days in a row now. Detailed photometry is provided below (dates/times are UT, year is 2023): 10.91 Aug.: 18.9 11.91 Aug.: 18.7 15.07 Aug.: 18.2 20.88 Aug.: 18.3 09.84 Sept.: 18.0 10.82 Sept.: 18.0 11.82 Sept.: 17.9 15.86 Sept.: 18.0 16.96 Sept.: 17.9 19.82 Sept.: 17.6 20.87 Sept.: 17.8 23.82 Sept.: 17.9 (bright Moon in the sky) 24.96 Sept.: 18.2 27.08 Sept.: 18.7 (very bright Moon in the sky) 01.76 Oct.: 18.4 02.76 Oct.: 18.8 03.77 Oct.: 18.6 05.82 Oct.: 18.9 06.78 Oct.: 18.6 08.00 Oct.: 18.8 08.80 Oct.: 18.8 09.77 Oct.: 18.9 11.85 Oct.: 18.8 12.85 Oct.: 18.7 13.76 Oct.: 18.5 Errors are around 0.1 mag. for the brighter values and around 0.3 mags for the fainter ones. The scenario summarized above suggests that the variable optical source we have discovered is the optical counterpart of a blazar. A spectrum taken on 24 Sept. 2023 upon our request at the Copernico telescope operated by INAF Osservatorio Astronomico di Padova in Asiago-Ekar under poor sky conditions, with a resulting low S/N ration, does not show obvious, strong features, this supporting our hypothesis of the blazar nature for this transient. Multi-wavelength observations are strongly encouraged. We wish to thank Lina Tomasella, Osservatorio Astronomico di Padova, Makoto Uemura, Hiroshima University, and Telescope Live for the precious support and fruitful discussion. Details about our work are available here: https://www.virtualtelescope.eu/2023/08/16/discovery-of-variability-of-the-optical-counterpart-of-the-nvss-j004354404634-radio-source-in-the-messier-31-field/ | N | |||||||||
| 185598 | 2023-08-22 10:48:00 | MASTER | Ya.Kechin, A.Sosnovsky, V. Lipunov et al. | MASTER | MASTER | 00:43:54.360 | +40:46:33.30 | 2023-08-22 00:12:04.032 | 18.2 | Clear- | PSN | MASTER OT J004354.36+404633.3 | MASTER | OT in M31 direction (possible Nova) | 2023TNSTR2040....1K | N |
Classification Reports
No Data
Comments