ASASSN-22ak = MASTER OT J225608.75-683610.6 = AT 2022ep

ASAS-SN light curve for the last 20 days (Shappee et al., 2014; Kochanek et al., 2017): https://asas-sn.osu.edu/sky-patrol/coordinate/71ac1722-3b66-4ef1-9ee2-2efe39...

Discovered at 15.0g on Jan. 07, peaked at about 13.2g on Jan. 08, faded to 13.6 by Jan. 09.

Detection by MASTER in Argentina on 2022 Jan. 09.039 UT: https://www.wis-tns.org/object/2022ep

Selected photometry:

ASASSN-22ak = MASTER OT J225608.75-683610.6 20220106.0797 <171g ASAS-SN last non-detection 20220107.0505 15.00g ASAS-SN (Shappee et al.; Kochanek et al.) 20220107.0530 14.90g ASAS-SN 20220108.0358 13.16g ASAS-SN 20220108.0384 13.20g ASAS-SN 20220109.0387 13.8CV MASTER-OAFA (Lipunov et al., 2010) 20220109.0432 13.8CV MASTER-OAFA 20220109.0674 13.61g ASAS-SN 20220109.0699 13.62g ASAS-SN

AAVSO VSX entry: https://www.aavso.org/vsx/index.php?view=detail.top&oid=2225886 Gaia EDR3: 22 56 08.86 -68 36 10.2 Plx=2.17(0.60) mas, pmRA=-10.77(0.55) mas/yr, pmDE=-10.01(0.82) mas/yr Gmag=20.43(1), BPmag=20.40(8), RPmag=20.24(12), BP-RP=0.16

With the minimum of 20.5V, the outburst amplitude is about 7-7.5 magnitudes.

Denis Denisenko