Nova Oph 2012 Fades Rapidly

After spending the past 3 months since discovery bouncing back and forth between V magnitude 10.5 and 12.5, Nova Oph 2012 has finally begun to fade. And what a fade! In just the past 24 hours the nova has faded by over 2 magnitudes. Over the past 48 hours the fade has exceeded 3 magnitudes.

Only a few days ago I posted (see post here) that Nova Oph 2012 was likely to be a ‘P’ or ‘plateau’ type of nova based on the shape of its lightcurve near maximum. Namely the nova spent months near maximum brightness. Well there is another type of nova described by Strope, Schaefer and Henden (2010) called the ‘D’ or ‘dip’ type. D-types experience a large sharp drop in brightness due to the formation of a dust shell around the nova which absorbs the light of the nova. As a result, less light gets through the dust and it appear fainter to us. Over time the dust clears and the nova starts to brighten again. Is Nova Oph 2012 a ‘D’ type. I’m certainly not a nova expert but for now we’ll just have to watch what other tricks this nova has up its sleeves.

Lightcurve of Nova Oph 2012. Plot includes visual and CCD V magnitude measurements. Observations overplotted with a cross were made by Carl Hergenrother. All observations are from the AAVSO. Plot created with the AAVSO Variable Star Plotter (VSP).

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