[vsnet-alert 24974] MGAB-V270 aka ZTF18abihypg superoutburst

[Denis Denisenko d.v.denisenko@gmail.com via vsnet-alert]

This AM CVn-type candidate in Cepheus [vsnet-alert 23718] is in bright
outburst in ZTF Lasair data, see
https://lasair.roe.ac.uk/object/ZTF18abihypg/

MGAB-V270
  20201116.1798  19.57r  ZTF (Masci et al., 2019)
  20201118.1802  14.99g  ZTF

This variable shows short dips to 18m five days after the peak followed by
the longer part of outburst at 16m. This behavior is thought to be of AM
CVn dwarf novae. Supercycle length from ZTF data is 173+/-2 days.

Position (J2000.0): 21 28 22.20 +63 25 57.5

Object is in opposition with the Sun in mid-August. But since the
supercycle length is close to 0.5 years, we  currently have one
superoutburst in spring and another one in autumn. If this cycle persists,
superoutbursts will occur 20 days earlier every next year (around Nov. 1 in
2021, Oct. 10 in 2022, Sep. 20 in 2023 and so on).

Denis Denisenko