Variable Stars - V1280 Sco
Type Slow Novae Click for lightcurve Slow novae that fade after maximum light by 3 magnitudes in ≥ 150 days. Here the presence of the well-known "dip" in the light curves of novae similar to T Aur and DQ Her is not taken into account: The rate of fading is estimated on the basis of a smooth curve, its parts before and after the "dip" being a direct continuation of one another. AAVSO Alert Notice 634, 11 May 2018 Nightly monitoring requested for V1280 Sco = N Sco 2007. Dr. Frederick Walter (Stony Brook University) has requested AAVSO assistance in monitoring V1280 Sco (Nova Sco 2007). After it appeared as a nova in February 2007 (AAVSO Alert Notice 346), V1280 Sco reached visual magnitude ~3.8 (several observers), then faded to about 13.2, rightened to about 12.7, and underwent a dust dip in June 2007 to <15.6 V (P. Nelson). It recovered to about 10.3 by about a year later. Dr. Walter writes: "It has been hanging in at V~10.3 for the past 8 years, after recovering from a dust dip. Recently, it dipped by over a magnitude in the optical bands, and has been slowly recovering. It did something similar about 200 days ago, after doing basically nothing for years. Questions abound about V1280 Sco. Why is it still bright (it has no obvious pre-outburst counterpart)? When will it finally fade? My best guess is that this nova occurred on a low mass white dwarf, so the ejected envelope is rather massive. The ejection velocities are slow (but there is, even now, a prominent outflow in He I), and the emission lines are cool (mostly Fe II) and narrow. It doesn't look like a normal nova now, but it reached third magnitude in 2007 and had a prominent dust dip. It just remains optically thick." Observers are requested to obtain nightly observations, ideally, filtered (V or B would be best), of V1280 Sco until further notice. Dr. Walter says that "a nightly cadence is needed to get a timescale for the entrance into the dip. While it is possible that nothing will happen for the rest of this observing season, good quality high cadence observations may reveal some underlying periodicities."
Hills Observatory: 1 January 2013 to 10 June 2019
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