[vsnet-alert 23884] DDE 158 = GALEX J140934.6-384610 outburst

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

This unusual cataclysmic variable in Centaurus at 103 pc (Denisenko and
Larin, arXiv:1807.04574) is in outburst on the recent iTelescope.Net images
from Siding Spring observatory.

DDE 158
  20200114.7407  15.76CV  T31
  20200122.7171  15.26CV  T32

According to Ckoirama observatory data from May 2019, the variable has an
orbital period of about 5 hours. This is a mystery, since the absolute
magnitude is M=11.1 at quiescence and M=10.3 in outburst (we called it a
"micronova"). Gaia parallax appears to be correct, since the proper motion
corresponds to the reasonable tangential velocity of 21 km/s.

DDE 158 spectrum from SOAR telescope:
http://scan.sai.msu.ru/~denis/DDE158-SOAR-2019Apr30.gif

There is no trace of the forbidden 6300 AA [OI] line, thus excluding the
possibility of DDE 158 being a young stellar object, as suggested by Pala
et al. (arXiv:1907.13152) in the lack of spectrum.

The next outburst is expected in late March - early April 2020 when the
star will be near the opposition with the Sun. The short (3-nights)
campaign from three continents (Australia, South Africa and South America)
will be needed to obtain the continuous light curve and to measure the
orbital period. Until then, the snapshot monitoring is encouraged.

Denis Denisenko