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A survey of British newspapers has uncovered 41 sightings of sunspots made by untrained people with no optical aid and without prompting. These truly accidental sightings mirror historical (pre-telescopic) western cases where there is no evidence of deliberate, intentional sunspot observation. The survey covered the period since 1874, when the Royal Observatory in Greenwich began compiling daily ledgers of sunspot sizes and positions from photoheliographic observations. This paper explains how candidate press reports were identified and then screened using objective criteria, and presents key results, in particular the circumstances under which the sightings were made, the sizes of the spots concerned, and indicators of solar activity (sunspot count, recurrence, geomagnetic storms) at the time. The survey found that 88 per cent of the accidental sightings were of sunspot groups whose whole spot projected areas exceeded 2,500 millionths of the visible solar disc, much greater than the 1,000 millionths usually quoted as a threshold for visual acuity. Furthermore, a spot 34,000 millionths in area was 100 times more likely to be noticed by accident than one with an area of 1,000-<2,000 millionths. Nearly all the accidental sightings were of recurrent groups and the associated mean sunspot number was >200. The possible implications of the results for the interpretation of historical sunspot reports are discussed. [ABSTRACT FROM AUTHOR]

Image denoising is an important consideration for improving the accuracy of acquired data. Given the morphological nature of astrophotography, with sparse star data overlaid on dim underlying background nebulae and galaxies, denoising is complicated to implement. New methods using convolutional neural networks and transformer networks show promise in general denoising applications. This paper explores the use of five recent denoising networks on astrophotography image data and demonstrates the feasibility as well as optimisations and pitfalls in the use of these networks. The paper confirms that image denoising in astrophotography using such networks is accurate and that a complete knowledge of ground truth might not be necessary for the accurate training of them. [ABSTRACT FROM AUTHOR]

Due to their discrete brightness and uncrowded appearance, open clusters are accessible to many amateur instruments. Moreover, their photornetric study allows evolutionary models developed for Population I stars to be tested. This paper presents a free interactive Excel application for this type of study. Among other things, it is an attempt to use Excel beyond its standard capabilities, applying it to a specific astronomical field. [ABSTRACT FROM AUTHOR]

Noctilucent cloud forms in the mesosphere at an altitude of about 83 km and appears annually in northern latitudes between the end of May and the beginning of August. A number of observers, situated at widely dispersed locations in the UK and Western Europe, report their sightings to the British Astronomical Association. This paper includes an analysis of these observations for the summer months of 2023, together with background information about the conditions in the mesosphere which contribute to the formation of polar mesospheric ice: the cause of ground-based sightings of noctilucent cloud. [ABSTRACT FROM AUTHOR]

In 1894, three Sydney members of the British Astronomical Association - John Tebbutt, Walter Gale and Robert Innes, all well-known astronomers-recruited 10 others to join them in appealing to the Council in London to form a local branch. This was granted on 1894 November 28, and the New South Wales Branch held its inaugural meeting on 1895 ]anuary 30. This paper looks at the 18 people from Sydney who were members of the BAA prior to the first meeting. That meeting created much local interest and many people joined immediately afterwards. The next cohort of 48 members admitted on 1895 March 1 is also discussed, with three people of note emphasised. A wide range of knowledge and expertise is found among the early members of the Branch, ranging from highly capable amateurs like the three founders, augmented by a small number of professionals, to those who made little or no contribution. [ABSTRACT FROM AUTHOR]

Harry Thornton and Leslie Rae were the Editors of the BAA Lunar Section publication The Moon from 1953 to 1967, during which period charting the lunar surface visually was superseded by professional astronomical photography and early space probe imagery. As a result, lunar contributions to The Moon dried up and, after Rae's resignation, the publication ceased. Thornton and Rae were very prominent figures in the BAA of the 1 950s and 1960s, yet no obituaries of them were ever published in the journal. The aim of this paper is to address those omissions. [ABSTRACT FROM AUTHOR]

This is the first of two papers in which, together, 28 previously unrecognised cases of probable aurorae seen iii the British lsles between 1560 and 1715, and over 100 newcandidatecases, are presented. It provides a resumé of the documentary sources for that period, brief accounts of the historical compilations of various luminous phenomena reported in the British Isles, and of more recent scientific catalogues of reported aurorae. Criteria for reviewing reports to distinguish probable aurorae from more doubtful ones are set out. For the period 1 560-1644,29 nights of probable aurorae are identified and documented, with extracts from original sources and full references. Of these, 14 are previously unrecognised. 14 less certain candidate cases are presented briefly, of which 13 are previously unrecognised. Misdated or untraceable catalogued aurorae are also documented. The period 1645-1715 is covered in the second paper, with an analysis of the combined results. [ABSTRACT FROM AUTHOR]

This paper covers observations of Venus made by Section members during the 2021-'22 eastern elongation. Although the planet was a difficult target for many observers, a reasonable number of observations were made, and we present our findings in this report. [ABSTRACT FROM AUTHOR]

This paper describes conditions leading to noctilucent cloud (NLC) sightings in the northern hemi sphere during 2021, reporting temperature and water vapour density at 83km altitude. It analyses reports made by observers in the UK and Western Europe, indicating the frequency with which NLC was seen and the location of the most southerly sighting for each night when it was observed. [ABSTRACT FROM AUTHOR]

We present the light curve of the dwarf nova DDE 39 (= 1 RXS ]040253.8+435553) between 2011 October and 2021 January, which reveals two bright outbursts: one in 2018 January and the one in 2020 December which is discussed in this paper. There is also evidence of two fainter outbursts: one in 2012 january and another in 2020 October, reaching magnitude 16.3 and 16.0 respectively. We report digital photometry of the 2020 December outburst. At its brightest, the system reached magnitude 15.1 - about four magnitudes above quiescence - and the event lasted at least 11 days. Superhumps with peak-to-peak amplitude of up to 0.4 magnitudes were present during the outburst, thereby establishing it to be a member of the SU UMa family. The mean superhump period, based on a linear analysis of superhump maxima, was Psh = 0·08176(235)d Period analysis of the superhump signal yields Psh = 0·08199(24)d. [ABSTRACT FROM AUTHOR]

The perihelic opposition that occurred on 2018 Jul 27 at areocentric longitude (Ls) 219° was monitored by 121 observers, yielding nearly 9,000 observations. Part I of this paper focuses upon the global dust storm that arose on 2018 May 30 in early southern spring, at Ls = 184°. The event was unprecedented in having commenced in the northern hemisphere, and the process of encirclement (over 25 days) was unusually slow. The expansion of the storm in both the northern and southern hemispheres was faster to the east than to the west. Its effects were still apparent in mid-August, and there were striking and long-lasting albedo changes including the reappearance of Phasis, the unprecedented distortion of the N. part of Margaritifer Sinus - Oxia Palus, and the intensification of Indus at SE Mare Acidalium - Niliacus Lacus. The global storm deposited dust upon the S. polar cap, accelerating its early recession, though the majority of the recession curve followed that of 2003 (a year without an encircling storm) extremely closely. Other global storm phenomena included terminator projections - due to suspended dust - up to some 80km in altitude, increased activity of the N. polar hood, and the presence of a bright morning limb cloud arc adjacent to the S. polar cap. Dust velocities of up to 118km h-1 were measured. In Part II, other local and regional dust storms are described, as well as white cloud activity and the behaviour of the polar regions. [ABSTRACT FROM AUTHOR]

This paper reports local times when afternoon clouds become telescopically visible for several locations on Mars. With the exception of dust storms, the times are consistent with historical records. It is concluded that late afternoon orographic clouds form near at least one of the four large Tharsis volcanoes throughout the Martian year. During 2018 and 2020, Argyre appeared as a northward projection on the South Polar Cap, near Ls = 170°. This is in line with the analyses of BAA observations reported by R.J. McKim for 1999 and 2001. [ABSTRACT FROM AUTHOR]

Paper I described the normal features of the North Equatorial Belt (NEB) in recent years. This paper describes an exceptional set of apparently coordinated changes which occurred in 2011-’12, after more localised precursors in 2008 & 2010. The large dark formations on the NEB southern edge (NEBs) progressively disappeared until none remained. In the sectors of NEBs thus vacated, smaller dark features all moved with unprecedented‘super-fast’ speeds, which were modulated by the few normal features while they lasted before accelerating further, reaching 139—151m/s. NEB ‘Rifts’ (expanding systems of convective white clouds) disappeared and the north half of the NEB progressively faded (whitened) until there was only a southerly NEB, at its narrowest and faintest in nearly a century. These changes have several profound implications for understanding the dynamics of the region. First, the NEBs took on the same appearance, dynamics and speed as the equivalent jet at 7°S (SEBn), supporting the view that the two jets are essentially symmetrical, with an underlying jet in the range - 150 - 170m/s. Secondly, the manifestation of this jet at the surface is normally suppressed by the presence of large slow-moving formations, which are probably Rossby waves. Thirdly, the loss of the large dark formations and the narrowing of the belt may have been promoted by the decline of convective rift activity. Lastly, these changes seem to represent a reversion to the situation before 1912, when such appearances were common and were followed cyclically by vigorous ‘NEB Revivals’. Indeed, just such a revival would ensue in 2012. [ABSTRACT FROM AUTHOR]

This paper covers observations of Venus made during the 2020-2021 western elongation. Although the Director only received observations from a limited number of individuals, this was still sufficient to provide a narrative of the various interesting phenomena recorded during this time and allowed an estimation of the date of true dichotomy to be made. [ABSTRACT FROM AUTHOR]

The Montes d'Alembert are a chain of mountain peaks found along the western lunar limb. The individual mountains were grouped into a Montes by Schroter in 1791 and were named after the French mathematician, philosopher and physicist Jean le Rond d'Alembert. About 175 years later, Lunar Orbiter images showed that the mountains are part of the complex landscape that is the result of the Orientale impact. Therefore, in 1970 the name Montes d'Alembert was dropped as official lAU nomenclature. There persists some indistinctness in lunar literature as to what the Montes d'Alembert represent. The aim of this paper s therefore to identify exactly where the peaks are on the lunar surface. It is found that the inner and outer Montes Rook, the Montes Cordillera and the radial facies of the Hevelius Formation all contribute. Libration dictates which peaks can be seen. [ABSTRACT FROM AUTHOR]

In this study, we examine four lunar domes located near the crater Lavoisier K, The domes, terrned Lavoisier 1-3, have large diameters of over 25km, with linear Miles traversing their summits and slopes of between 0.5° (Lavoisier 1-2) and 0.7° (Lavoisier 3). Another lunar dome, termed Lavoisier 4, has been identified using telescopic imagery, while in LROC WAC imagery it is not apparent. It has a base diameter of 5.7km and a height of only 4Om, resulting in a slope angle of 0.76°. Based on rheologic models, we infer the physical conditions under which the examined domes were formed. The main goal of this paper is to promote serious lunar research among dedicated amateur astronomers who are interested in observing and imaging the surface of the Moon, aswell as in its geological history. In combination with high-resolution spectral analysis techniques, such investigations might extend our present knowledge of the processes that formed volcanic edifices on the Moon. [ABSTRACT FROM AUTHOR]

Remarkably, the five largest recorded sunspot groups all occurred during a period of just over five years, from 1946 February to 1951 May, during Solar Cycle 18. These are the only groups known with areas greater than 4,500 millionths of the Sun's visible hemisphere. This paper examines the white-light activity of the groups. [ABSTRACT FROM AUTHOR]

Since the invention of the telescope, observers of Venus have often reported irregularities in the shape of the planet's terminator and cusps. Some of these, such as terminator undulations, might be easily ascribed to poor seeing conditions; others, such as cusp extensions near inferior conjunction, are undoubtedly real and evidence of Venus's atmosphere. This paper considers a third category: detached points of light recorded by several observers at the cusps of the planet, explained by some as high mountain peaks catching the sunlight. Among those who argued for the existence of such mountains was Johann Schrater, a stance that brought him into conflict with the views of William Herschel. Nowadays the 'ghost mountains of Venus' are seen for what they are: an illusion encouraged by a growing belief in the plurality of Earth-like worlds. [ABSTRACT FROM AUTHOR]

In the early hours of the morning of July 12 in the year 1822, Franz von Paula Gruithuisen (1774-1852) turned his small telescope to the Moon. What greeted him at the eyepiece, in the environs of the crater named Schroeter, was nothing short of a revelation. The jumbled terrain, caught under raking illumination, coalesced into a regular arrangement which convinced the astronomer he had discovered evidence that the Moon was inhabited. Two years later Gruithuisen published a lengthy paper in which he presented many evidences to suggest this. However, it was his initial discovery in 1822, an episode which became known as the 'City in the Moon', which has become his most published account. This short paper outlines a similar feature recorded by Gruithuisen and revisited by T. W. Webb (1806-1885) in his Celestial Objects for Common Telescopes. Conclusions are drawn from Webb's account which suggest why this episode, similar in general terms to the 'City in the Moon', is not more widely known. [ABSTRACT FROM AUTHOR]

Eclipse time variations have been detected in a number of post-common envelope binary systems consisting of a subdwarf B star or white dwarf primary star, and cool M-type or brown dwarf secondary. In this paper we consider circumbinary hypotheses of two sdB systems, HS 0705+6700 (also known as V470 Cam) and NSVS 14256825, and one white dwarf system, NN Ser In addition, and for comparison purposes, we investigate the eclipse time variations of the low-mass binary system NSVS 01286630 with its stellar circumbinary companion. All four eclipsing systems have claims of circumbinary objects with computed physical and orbital parameters. We report 108 new observations of minima for these systems obtained between 2017 May and 2019 September and combining these with all published data, we investigate how well the published circumbinary object hypotheses fit with our new data. The new data have shown departure from early predictions for three of the four systems, but it is premature to conclude that these results rule out the presence of circumbinary objects. There is also the possibility (but with no observational proof so far) of detecting close-in transiting circumbinary objects around the systems, but these are likely to have periods of days rather than years. [ABSTRACT FROM AUTHOR]

This paper describes how a small refractor can readily be taken on observing trips abroad as airline cabin baggage. [ABSTRACT FROM AUTHOR]

John Glasby was a popular Director of the BAA Variable Star Section from 1965-71; an exciting period during which George Alcock discovered three novae. Glasby's legacy is still felt today, because he steered the Section towards more observations of cataclysmic variables as well as starting a binocular variable star programme. He also wrote three books on the subject of variable star observing, filling a major gap in the literature, along with hundreds of works of pulp fiction. Unfortunately, so much controversy surrounded major errors in his BAA reports that any positive contribution he did make has long since been forgotten. This paper is an attempt to unravel the complex enigma of John Glasbys directorship and the set of unfortunate circumstances that damaged his astronomical reputation. [ABSTRACT FROM AUTHOR]

Paper II described the extreme changes in Jupiter’s North Equatorial Belt (NEB) which took place in 2011-’12:quiescence, narrowing and fading of the belt, along with acceleration of the prograde NEBs jet to super-fast speed. Here we describe how this anomalous state was terminated in 2012, in a rapid and vigorous disturbance known as an NEB Revival - the first in living memory. At the same time, the North Temperate Belt (NTB) had entered a similar preparatory state, which was terminated by an NTB Revival initiated by a typical outbreak on the super-fast NTBs jet. The two concurrent Revivals appeared to constitute a ‘great northern upheaval’ extending from the equator to ~38°N, which may have been the first such event ever recorded. We compare this dual event with the more typical ‘global upheavals’, which consist of near-simultaneous Revivals of the NTB and the South Equatorial Belt (SEB), along with equatorial coloration. W e also discuss the current understanding of global upheavals. [ABSTRACT FROM AUTHOR]

This paper examines claims that the explorer Henry Hudson saw sunspots with the naked eye during sea voyages in both 1590 & 1609. It is argued that there is no evidence to link Hudson with the 1590 observations, and that the presumed sunspot of 1609 - accepted by some leading experts in the history of solar activity-is based on a false premise. [ABSTRACT FROM AUTHOR]

Alice Grace Cook (1877-1958 and usually known by her middle name) was one of the first female Fellows of the Royal Astronomical Society. She was also briefly the Director of the British Astronomical Association Meteor Section. However, she is a little-known figure. This paper presents an overview of her life and contributions to astronomy. [ABSTRACT FROM AUTHOR]

This report describes the observations of Saturn made by Saturn Section members during the 2008/2009 apparition. During this apparition, the rings were edge-on to the Sun and Earth on 2009 Aug 11 and Sep 4 respectively. The former event was difficult and the latter impossible to observe from the Earth as both occurred close to solar conjunction on Sep 17. During the apparition both major belts were visible and observations showed that the North Equatorial Belt (NEB) had a noticeable blue colour compared to the warm colour of the South Equatorial Belt. A number of storms were observed during this apparition and four of these were reliably followed. Evidence is also presented that shows that one SEBZ storm had lasted over at least three apparitions. Observations of a number of satellite and shadow transits and Titan eclipses will be presented in Part II of the paper. [ABSTRACT FROM AUTHOR]

This paper presents evidence for a probable aurora australis report and persistent recurrent solar activity in the year 1580. [ABSTRACT FROM AUTHOR]

This paper reviews the combined video meteor spectroscopic observations of the Kilwinning Spectroscopic Survey for Meteors (KiSSMe) and the related mutual capture, multi-video station orbital observations from the Network for Meteor Triangulation and Orbit Determination group (NEMETODE) in the period between 201S April and 2016 April.A total of eleven mutual events were captured. A brief comment is made about the main lines in each spectrum and orbital elements are presented for eight of the meteors. [ABSTRACT FROM AUTHOR]

In this paper we review telescopic observational data of Mercury from 2007 November to 2016 October inclusive, and describe the results of the 2016 solar transit. A gradual im provement in imaging technique has enabled observers to record albedo features upon Mercury's surface as well as many bright patches corresponding to the ejecta regions of bright craters. An albedo chart and a Messenger map are presented for comparison. At the solar transit, observers obtained images in white light as well as in the wavelengths of Hydrog en alpha and Calcium K, timed the various contacts, and re-observed certain optical effects, comparing the results with those obtained at previous events. [ABSTRACT FROM AUTHOR]

This paper considers past and future appearances of the southern constellation of Crux in the skies of Britain. [ABSTRACT FROM AUTHOR]

Ole Rømer (1644-1710) is remembered to day for establishing, from ob servations of eclipses of the Galilean satellites of Jupiter, that the velocity of light is finite.This paper describes the use of amateur timings of Galilean eclipses observed during 2012-14 to recreate Romer's work, together with a theoretical investigation of the accuracy of such approaches for estimating the speed of light. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to bring to the attention of the amateur astronomical community the writer's discovery of a previously unknown class of object, the significance of which does not appear to have been reported in amateur publications. The object, designated SN2008S, is still causing much interest, debate and controversy some 7 years after its discovery. The writer describes historical supernovae in the parent galaxy, NGC 6946, the actual discovery details, and the initial classification. The discovery of a very faint progenitor that was not visible in deep optical images but was relatively bright in the infrared, sparked widespread interest. Realising that this was a most unusual object, several diverse observational programmes followed, some involving the use of NASA's Hubble and Spitzer Space Telescopes which are still ongoing. Briefly described is the possible physical nature of the progenitor star and the various proposed astrophysical models behind the explosive event. Whatever the outcome, SN2008S is a new class of optical transient believed to be somewhere between a nova and supernova. [ABSTRACT FROM AUTHOR]

William Sadler Franks (1851-1935) was astronomer-in-charge at F.J. Hanbury's private observatory at Brockhurst, near East Grinstead, Sussex, from 1909 until his death in 1935.This paper reviews the observational projects Franks undertook at Brockhurst, including his work on double stars, red stars, diffuse nebulae and dark nebulae, as well as his involvement with the commissioning of a 24-inch reflector built by Thomas William Bush (1839-1928). [ABSTRACT FROM AUTHOR]

The article presents a research paper discussing the concept of an active lunar. It mentions that before the Space Age astronomical investigation was only possible by proxy, via the eyepiece of the telescope, it was therefore only natural to try. It also mentions a book "The First Men in the Moon" by H. G. Wells.

The article describes the life and astronomical interests of the Reverend Walter Bidlake of Crewe. The use of the celestial photographs of Bidlake in the paper "Dark Structures in the Milky Way" by British Astronomical Association (BAA) member Revd T. H. E. C. Espin is emphasized. A libel case filed by Bidlake against Emma Mary Fulham who claimed her was to marry her is highlighted.

The article offers information on the 3rd Ordinary Meeting held at the Royal Astronomical Society, Burlington House in Piccadilly, London, England on January 31, 2015. It mentions that Jeremy Shears, Papers Secretary, read the titles and authors of five papers accepted for publication. It also mentions views of Konstantinos Dimopoulos, a reader in physics.

The article offers information on the 3rd Ordinary Meeting held at the Royal Astronomical Society, Burlington House in Piccadilly, London, England on March 25, 2015. It mentions that Jeremy Shears, Papers Secretary, read the titles and authors of five papers accepted for publication. It also mentions views of Professor Jonathan Rawlings of University College London, England.

SDSS J082053.53+000843.4 belongs to the HW Vir family of short period binary systems and was first identified by Geier in 201 I.W hils t three subsequent papers have focused on the morphology of this system, little has been published on the system period and its constancy. Here we provide the first published times of minima together with a revised ephemeris and a binary period, 0.0962404(l)d, that is four orders of magnitude more precise than previous declared values. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at Royal Astronomical Society, Burlington House, Piccadilly in London, Wisconsin, held on March 30, 2016 is presented. Topics include the papers on comets, structure of comets and solar system's satellites. The meeting featured President Dr Jeremy Shears and Dr Axel Hagermann.

The article discusses an Ordinary Meeting sponsored by the British Astronomical Association that was held at the Royal Astronomical Society in England on October 28, 2015. Topics discussed include details from the Association's new president Jeremy Shears on papers related to solar and lunar eclipses that will be published in 2016, Pluto's atmosphere and satellite Charon, the U.S. National Aeronautics & Space Administration's (NASA) New Horizons spacecraft.