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An indicative unfiltered light curve has been generated for the protostar R CrA. During the period 2018 May to 2020 November, the variability was seen to be substantial (11.5–13.1), but only weakly compliant with the 65.7-day variability generally attributed to R CrA. The star illuminates the fan-shaped NGC 6729 nebula. Variability in the nebula was observed to begin close to R CrA and then move steadily down the fan, fading as it progressed. Measurements of the surface brightness of the different parts of the nebula showed an apparent relationship in the delay between brightening of R CrA and the subsequent brightening of parts of the fan. These variations appear consistent with light echoes.

Until now there has never been a comprehensive account of Jupiter’s 1949 apparition, in which there was a Revival of the South Equatorial Belt (SEB). On opposition day, Jul 19, despite the SEB south component not having faded to invisibility, the first white spot of the Revival was seen. The spot had originated within a pre-existing SEB(S) dark ‘barge’, close to the longitude of E. J. Reese’s ‘Source B’. The Revival led to a fading of the initially conspicuous Great Red Spot (GRS), and the development of the Red Spot Hollow (RSH). The S. branch of the Revival was weak, with small retrograding dark spots which failed to pass the GRS, although their velocity was typical. The N. branch was also less active, with some prograding dark spots passing only slightly beyond the GRS/RSH, which also exhibited a typical drift. On the other hand, the central branch was unusually active, with a succession of long-lived white spots and dark columns (mean drift rate Δλ2 = –67°/30 days). The p. end of the Disturbance in …

By observing the polar regions of the Sun on three occasions and in three wavebands, polar faculae in the photosphere were studied and compared to features found in the chromosphere at wavelengths of calcium II K and hydrogen-alpha. It was found that the white-light polar faculae are closely associated with calcium II K bright plage, but more tenuously associated with hydrogen-alpha plage. Associations were more consistent for hydrogen-alpha mottles, although non-specific correlations could not be excluded.