The old Nova GK Per (N Per 1901) may be entering outburst. Latest observations shows a nearly 0.5 mag rise in less than one day from 13.0 to 12.6 (Oct 1.9UT – Oct 2.6UT)
GK Per began Dwarf Nova type outbursts in the mid 1960’s, ~60 years after being discovered by the Rev. Thomas David Anderson on Feb 22nd, 1901 at mag 2.7, peaking a few days later at magnitude 0.2. The outbursts occur at roughly 3 yearly intervals, with the last one being in August 2018, peaking at magnitude 10 and lasting about two months.
Superluminal echoes were first discovered in this historic Nova by Flammarion in 1901, and in the 1980’s X-rays were discovered from the system, leading to a more precise classification of GK Per as a magnetic CV – an Intermediate Polar – where the inner part of the disc is truncated by the magnetic field of the White Dwarf.
GK Per is well placed in the evening sky at the moment, and further observations (visual, CCD, spectroscopic) are encouraged to confirm whether this is indeed the expected outburst or a minor brightening – which can occur.
Observations from last night and this morning (Oct 3-4) show very little change in the brightness of GK Per, so the outburst announcement which appeared on various VS mailing lists MAY have been a little premature. However an outburst is due sooner rather than later, so please keep your eyes on it.