2021 August 9
Eruption of the Recurrent Nova RS Oph
The Recurrent Nova RS Oph is in eruption. It was reported at mag 5 last evening (Aug 8) by Alexandre Amorim and Eddy Muyllaert:
Aug. 7.969 11.2v Alexandre Amorim
Aug. 8.913 5.0v Alexandre Amorim
Aug. 8.920 5.1v Eddy Muyllaert
Aug. 8.931 5.1v Keith Geary
RS Oph last erupted in Feb 2006. Observations of all types are urgently requested by the BAAVSS. BAAVSS charts can be downloaded here.
At mag 5, it is borderline naked eye visibility, although binoculars will be the most appropriate instrumentation in the initial stages. Do try to witness this important piece of history! The unfolding story will be covered on the BAA Forum.
In quiescence, RS Oph is normally about mag 12.5. It has been observed to erupt in 1898, 1933, 1958, 1967, 1985, and 2006. It reached about mag 5 on average. A further two eruptions, in 1907 and 1945, have been inferred from archival data.
RS Oph is located at RA 17 50 13.17 Dec -06 42 28.6 (J2000.0)
A BAA VSS light curve of the 2006 outburst:
Director, Variable Star Section
Image credits. Teaser image: ESO, radio profile of RS Ophiuchi, together with the fireball as seen by VLTI 5.5 days after the 2006 outburst. Chart of RS Oph: PopePompus from Wiki under Creative Commons licence