Low-state transitions in the nova-like cataclysmic variable HS 0506+7725

The twelve-year lightcurve of the nova-like cataclysmic variable HS 0506+7725 between 2006 April & 2018 November is presented. This shows that the star spends most of the time in a normal state at about magnitude 14.7, but multiple excursions to a fainter state at magnitude 16.0–17.0 were apparent. These normal-state/low-state transitions of up to 2.3 magnitudes are typical of the VY Scl subclass of CVs. In the case of the best characterised fading episode, both the fading and the subseqent return to normal brightness were observed; the complete transition lasted about 43 days. Further monitoring of this system by amateur astronomers is encouraged to identify and characterise future low states.

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The larger sunspot groups of Cycle 24

Using observations submitted to the BAA Solar Section, the largest sunspot groups of Solar Cycle 24 are discussed and example images shown. The characteristics of the cycle are also described and a comparison is made between the sizes of its larger sunspot groups and those of previous cycles, stretching back over 100 years.

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