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The Gaia space observatory provides parallax values for stars, allowing us to determine their distances. Young star clusters are located close to the galactic plane where their formation took place. The distances of fifty young clusters have been computed, allowing us to see how they are distributed in the Milky Way galaxy. This distribution provides us with evidence of the shapes and distances of the spiral arms in which they were formed.

In this study we examine a lunar dome, termed Laplace 1 (L1), identified using telescopic, LROC WAC and Chandrayaan-1 Moon Mineralogy Mapper imagery; Mineral Mapper reflectance data acquired by the JAXA probe SELENE/Kaguya; the LOLA digital elevation model and the LROC WAC-based GLD100 digital terrain model. The dome lies at coordinates 48.57°N and 26.37°W, about 36km south-east of the crater Maupertuis. It has a base diameter of 7.6 ± 0.3km and a maximum height of 230 ± 20m, resulting in a slope angle of 3.4 ± 0.3°. Spectral data indicate a basaltic composition. We assess the regional geology and infer the physical conditions under which the dome originated. L1 is not reported in lunar dome catalogues; hence our study demonstrates that high-resolution CCD imagery is useful for the recognition of non-catalogued domes. The main goal of this paper is to promote serious lunar research among dedicated amateur astronomers.

David Sinden, an amateur astronomer and former member of the BAA, was the last in a line of opticians that can be traced back to Thomas Grubb. For many years he was chief optician at Sir Howard Grubb, Parsons and Company where he worked on optics for some of the world’s largest telescopes made at the time. He went on to establish his own business, the Sinden Optical Company, before his untimely death in 2005. He was a highly respected and skilled optician whose achievements were considerable. Many of his optics are still in daily use in observatories around the world.