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A sequence of IR images taken by Pete Lawrence using a 356mm SCT. The nightside was captured using an ASI 224MC at 1,000nm, while the illuminated crescent was captured using an ASI 174MM at 742nm. The two images were then combined to give a single image, showing the nightside and a crescent which is not over-exposed. Images (c) and (d) were processed with artefact reduction and masked to remove stray light patterns. Dates for each image are as follows, (a) 2020 Apr 25, (b) 2020 May 2, (c) 2020 May 4 and (d) 2020 May 5.

The 2019–’20 eastern elongation of Venus, Part II: Observations of the nightside

Presented here is an analysis and discussion of observations made of the nocturnal hemisphere during the 2019–’20 eastern elongation of Venus. These observations of the infrared thermal emission are crucial to the Section’s aim of investigating active volcanism on the planet. We also discuss research by professional astronomers at the Swiss Federal Institute of Technology, supporting the idea of active volcanism, and how the results obtained by Section members thus far support this conjecture.

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The simulated appearance from Earth of the VV Cep binary system at phase 0.95, approximately 12 months before mid-eclipse at phase 1.0 (anti-clockwise orbits), near the anticipated time of first contact of the gas disc circulating anticlockwise around the hot blue star (for visibility the blue star diameter is significantly exaggerated). This is a snapshot from a video made by the author using the Nebraska Astronomy Applet Project’s Binary Star Simulator, astro.unl.edu/naap/ebs/animations/ebs.html. Orbital parameters are taken from Hopkins et al. (2015).

Observing the 2017–’19 primary eclipse of VV Cephei with a low-resolution spectroscope

The 2017–’19 primary eclipse of the red supergiant star VV Cephei has been monitored with low-resolution spectroscopy, by following changes in the hydrogen Balmer emission lines in the spectrum. A number of characteristics of the binary system are derived from the high cadence of observations, including a surprising estimate of 7,425 days for the orbital period since the midpoint of the last eclipse. The appearance of the spectrum near mid-eclipse has also provided a means to estimate interstellar reddening.

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