Dear friends,

Using my private system scraping MARS ( https://mars.lco.global ), I've just found ZTF21aceejop out as a CV candidate from the public ZTF data. Its amplitude is > ~ 6.0 mag (assuming the limiting mag of PS1-g is 21.6). (I'm sorry if someone has already discovered and reported it elsewhere.)

Lasair: https://lasair.roe.ac.uk/object/ZTF21aceejop (The page has not existed now) ALeRCE: https://alerce.online/object/ZTF21aceejop MARS: https://mars.lco.global/?objectId=ZTF21aceejop

According to ALeRCE, the position is (RA, Dec) = (07:45:50.452, +56:15:28.07)

The result of ASAS-SN Sky Patrol: https://asas-sn.osu.edu/sky-patrol/coordinate/25c2fb07-72d2-457b-8cc7-a45601... It also confirms the present outburst. It looks there are no past outbursts recorded.

Last non-detection by ZTF:  r > 19.7033 on 2021-09-26.51 (ZTF, 'difference mag' via ALeRCE)

First detections by ASAS-SN: g = 15.422 on 2021-09-29.5728358 g = 15.508 on 2021-09-29.5740966 g = 15.444 on 2021-09-29.5753592

First detections by ZTF: g = 15.665 +/- 0.029 on 2021-09-30.47 (ZTF, 'difference mag' via ALeRCE) r = 15.974 +/- 0.028 on 2021-09-30.50 (ZTF, 'difference mag' via ALeRCE)

The object is ~ 2'' north of WISEA J074550.52+561525.6, which is r = 21.2 according to the PS1 mean object catalog. No known minor planets are found by the Minor Planet Checker ( https://www.minorplanetcenter.net/cgi-bin/checkmp.cgi ).

Best Regards and Clear Skies, Kenta