J. Brit. Astron. Assoc., 108, 6, 1998, p.337-338
J. Brit. Astron. Assoc., 108, 6, 1998, p.337-338
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From the Director of the Aurora Section
Jean Meeus of Erps Kwerps, Belgium has written to point out that in my recent article on the Sun's effect on technology,[1] I stated that the manned lunar landings had been programmed for quiet periods of solar activity around sunspot minimum. In fact the landings took place just after sunspot maximum and into the declining phase of the cycle. Sunspot maximum was at February 1969 with a secondary maximum in April 1970, to be followed by sunspot minimum in 1976. I apologise for this error.
Accepting activity in the geomagnetosphere as an index of solar activity I looked up the magnetic index aa for the dates of each Apollo lunar landing mission (Table 1). The aa index is based on observations of magnetic activity at antipodal observatories set up in 1973 by P.-N. Mayaud, although he was able to reconstitute aa values back in time to 1868. I have copies of the indices from 1868 to 1987 given to me by Dr J.-P. Legrand of INSU in France. The indices are related to the state of the solar wind with the following numbers:
For example, shock wave activity on 1958 July 8 sent the aa index up to 305 and on 1986 February 8 aa rose to 244.
The annual totals of aa indices for the years concerned are given in Table 2. It would appear that the earlier Apollo missions were flown in quieter solar wind periods although closer to sunspot maximum.
Ron Livesey
Flat 1/2 East Parkside, Edinburgh, EH16 5XJ
[1] Livesey R. J., 'The Sun, interplanetary weather and mankind's technologies', J. Brit. Astron. Assoc., 108(4), 208 (1998)
From Mr Peter Parish
Following my letter in the August Journal describing observations of Venus and Jupiter in daylight, I decided to see if it was possible to observe Venus and the much fainter Mercury. At 04 55 GMT on Friday 1998 September 11 at about 35 minutes before sunrise, I saw Venus and Mercury with the 10×50s and naked eye in a pale blue/pink dawn sky. They were under half a degree apart and well within the same binocular field. Knowing the two planets' relative positions to each other assisted me on the following day.
At 08.00 GMT on Saturday September 12 the sky was a deep rich blue but from where I was situated in my garden, the brilliant Sun was safely hidden behind my neighbour's house close by. After a little searching with the 10×50s I located Venus. The planet was invisible with the naked eye but a very bright starlike object in the binoculars. In the bright white-blue sky where I was looking, I tried to allow for Mercury's forward motion eastwards relative to Venus since yesterday and to my joy I perceived it as a faint star still well within the same binocular field as the much brighter Venus. From that moment I observed both planets off and on. By 09.05 GMT Mercury was noticeably easier to see in the 10×50s alongside Venus. Maybe this was due to its increased height; the Sun itself was now 32° high. For some time cloud had been gathering and approaching from the west and a few minutes later both planets were hidden. The cloud lasted until 13.05 GMT when I was blessed with another clear blue mass of sky. Seeking a spot in the garden hidden from the Sun, I picked Venus up once more in the 10×50s. Alongside it to the left, Mercury's little starlike point was even clearer than it had been in the morning. My daytime view lasted this time until 13.40 GMT when cloud again interrupted. I had one more chance at 14.35 GMT. In the binoculars Mercury's starlike point was still very clear alongside the much brighter Venus.
The following day (Sunday 1998 September 13) the morning was overcast but at 12.30 GMT the sky cleared for ten minutes. Through a blue sky made slightly milky by very thin high altitude cloud Mercury's starlike point was still clearly visible. The much brighter starlike dot of Venus was visibly further to the right of Mercury than on the previous day but both planets were still well within the same binocular field of view. As on the previous day, Venus was not visible with unaided vision.
Seeing Venus high in the sky was satisfying but seeing our innermost planet to the Sun was even more so. Indeed until these observations I've described I had never seen Mercury high in the sky.
Peter Parish
30 Wooldeys Rd, Rainham, Kent ME8 7NU.
From the Director of the Historical Section
In her informative article on Elizabeth Brown,[1] Mary Creese says she was probably the only female astronomer in the country at the time to have her own observatory. I would like to beg to disagree. The nineteenth century, especially during the late Victorian period, was to see a burgeoning interest in astronomy amongst the female sex.
One example was Mary Ashley, who was born in Shirehampton, Gloucestershire, about 1843 and who died on 1903 March 28 in Bath. What in particular attracted me to her was that she lived in 16 New King Street, just a few houses away from Herschel's home, 19 New King Street. Her father was the Revd John Ashley, DD, and she had at least one sister (Kate) and brother (John, who emigrated to New South Wales and may have died before November 1896). From the little information I have so far been able to obtain, she appears to have had an independent income. Her active interest in astronomy dates from the 1870s–1880s as surviving observing notebooks on the Moon and Jupiter would indicate. These and some other items came to the library of the BAA (although when is as yet unknown) where they still exist. That she seems to have been held in some regard can be seen in the notice to her in A. Rebière's Les Femmes dans les Sciences (1897, second edition, Paris). Her notebook drawings of Jupiter (1880 July 21–1883 March 15) were made using a 3¼-inch and 4-inch Wray refractor. The observations appear in line pencil and either crayon or pastel. Some drawings have an accompanying narrative, while some show the Great Red Spot and the major satellites.
The lunar notebooks consisted of at least seven volumes, the contents of which are as follows:
Correspondence from herself has appeared in the following issues of the Selenographical Journal: III (1880 May 9, on Hyginus N); IV (1881 September 23, on the cleft near Hyginus D); V (1882 February 18, a note in connection with Mr Hutchings' and Mr Neison's Letters of the Rill near Hyginus D) as well as a letter to The Observatory magazine (1(6) 277) on an eclipse of the Moon. It is possible that she also communicated to other publications (e.g. the English Mechanic), but this has not yet been discovered. She was a member of the Selenographical Society and of the Liverpool Astronomical Society (1884). From this it can be seen that it is very probable that she had her own observatory, as there is no mention of her using that of someone else. Although the BAA received donations from her estate (principally from her library), she does not seem to have been a member, as her name is not on the roll of members for the period 1890–1903.
Very little is known of Mary Ashley's career after the mid-1880s, and she appears to have ceased active astronomical work from this time. A copy of her (beautifully written) last will and testament mentions various members of her family, including her brother and sister, and a cousin, who acted as executor. I would greatly appreciate it if any reader who has information on the family could contact me, especially from New South Wales. I would be glad to provide what little information I have, including a copy of the will.
Anthony Kinder
16 Atkinson House, Catesby Street, London SE17 1QU.
[1] Creese M., 'Elizabeth Brown, Solar Astronomer', J. Brit. Astron. Assoc., 108(4), 193–197 (1998)
From Mr James Abbott
The Campaign for Dark Skies carries out excellent work in trying to ensure that light pollution is checked, but I fear that some sources of artifical light are increasing beyond our influence. During a meteor watch on the evening of Perseid maximum night, 1998 August 12/13, I took the opportunity to make a count of all light sources that caught my attention, in addition to meteors. I have a fairly dark site, with no local streetlights. In one hour between nightfall and moonrise, I observed a modest 16 meteors. But in addition to some satellites and the occasional brief intrusion of a security light, I also observed no fewer than 60 aircraft.
With air transport likely to treble on the 1990 level by the year 2010, our skies are going to be increasingly blighted by aircraft lights, especially here in the southeast of England. Satellite launches continue apace. We already have 'glints' from the Iridium satellite system and there are proposals for lighting parts of the Earth in winter darkness using orbiting solar reflectors. Then there is the possibility of space advertising. Taken together, I would suggest that whilst we may be able to make progress with more appropriate and sensitive modern fixed lighting installations in urban areas and along roads etc., economic pressures are leading to growth in non-ground-based sources of artificial light, and disturbance from these will unfortunately worsen.
James Abbott
1 Waterfall Cottages, Park Road, Rivenhall, Witham, Essex CM8 3PR
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