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Observations at long infrared wavelengths by the Akatsuki spacecraft during 2015 December revealed the presence of a remarkable bow-shaped high-albedo atmospheric wave, elongated north–south and stretching over both hemispheres across a wide range of latitudes, up to 10,000km in length. Its velocity was nearly zero with respect to the surface, and its initial longitude placed it at the western side of one of the three highest regions of the planet. Amateur data at shorter infrared wavelengths recovered long, narrow N–S elongated waves or discontinuities in late 2016 and again during 2019–’20, but they showed typical velocities for that waveband, corresponding to synodic rotation periods of around five days. This short note reviews the Akatsuki data and more recent ground-based observations. Furthermore, it speculates whether waves could also have been generated by the possible surface volcanic activity first reported in BAA observations during 2017.

In this study we examine five lunar domes in Mare Fecunditatis. These domes, termed Messier 3–7, have moderate diameters between 5.6 and 15km, with slopes of between 3.2° (Messier 4), 1.5–1.6° (Messier 5–6) and 0.5–0.87° (Messier 7 & 3). Based on rheologic models, we infer the physical conditions under which the domes were formed (lava viscosity, effusion rate and magma rise speed) as well as the geometries of the feeder dikes, comparing them with the domes Messier 1–2 described previously by Lena et al. (127(6), 338–349, 2017). Furthermore, we have identified and characterised three lunar cones and several small ‘ring moat dome’ structures. These structures have recently been identified as widespread on the maria and are thought to be volcanic in nature, possibly involving the extrusion of magmatic foam.

Henry Prescott lived during the second half of the seventeenth century and early part of the eighteenth century in Chester, Cheshire. Although not an astronomer, Henry was moved to record a number of astronomical observations in his diary after witnessing some spectacular celestial events. This fact was remarked on as an aside by a speaker at a local history lecture attended by the author, sparking his desire to research what these observations were. Finding out more about Henry and his observations has been an enjoyable journey, with some connections Henry had with well-known astronomers of the day identified along the way. This paper reviews these observations and connections, while also including side stories involving some of Henry’s associates. Brief references are made in some cases to other people’s observations of the events reported by Henry in his diary, to provide confirmation and supporting information.