American Association of Variable Star Observers (AAVSO)
Thu, 02/29/2024 - 20:48

Berto Monard has reported to vsnet-alert that the recurrent nova V0745 Sco is brighter than usual.
He found it rising to V= 15.5 last night (Feb. 28-29).

The rising rate, however, is not fast enough to suggest a recurrent nova outburst, since the star would have reached its peak in a matter of hours, and the previous night it was already at V= 15.9.
Two weeks ago it was at V= 17.9 so the brightening is apparent.

There is a highly variable red giant in the V0745 Sco system so it might be responsible for what is happening, but it would be interesting to take a look.

The OGLE light curve in the Ic band (Ic= 12.8-13.8) between 2001 and 2009 shows pulsations and some spikes that might be coming from the white dwarf. The amplitude in the visual is much larger (V= 16.2-18.7) so it would be interesting to see what's going on.

Having said that, and even when observations are encouraged, care should be taken when measuring this field. The remark in VSX states:

"16.9 Vmag. star 5" to the E, 15.9 Vmag. star 8" to the WNW, 17.2 Vmag. star 9" to the W, 16.5 Vmag. star 9" to the N and 16.0 Vmag, star 10" to the NE."

So it is important not to confuse the target with one of these nearby stars, and also keep it separate from the companions when doing aperture photometry.
Just be warned and see what you get!

Best wishes,