J. Brit. Astron. Assoc., 106, 2, 1996
(Note: The Association is not responsible for individual opinions expressed in articles, reviews, letters or reports of any kind.)
From Mr G. C. Sallit
As an ex-member of the BAA I would like to comment on Martin Mobberley's letter about me in the February Journal.
I was originally asked by a member of the Reading Astronomical Society to present a report on this to the local radio station. The main idea was to show that unlike most scientific hobbies amateurs can make valuable contributions. These contributions have been recently enhanced with the availability of computer controlled telescopes and CCDs. The follow up press interest certainly surprised me and the reasons for it are covered in a co-authored article in Astronomy Now.
In my interviews I mentioned the fact this observation was done in partnership with Dr Adrian Catterall and the work of Manning, James, Hurst and others in this area, but all these people were not mentioned. I became aware of Stephen Laurie's work after later discussions with Guy Hurst but again the press were not interested in reporting this. I will not apologise for the press.
I have, so far, refrained from commenting on the IAU reporting procedures for observations. The process is complex, confusing, unfair and open to misunderstanding. I have left the BAA for a variety of reasons, but I welcome the setting up of a group by Ron Arbour (and others) to confirm CCD observations and admit that it would be one of the reasons for returning to the BAA.
George Sallit
Jacinth, Stanford Road, Southend, Bradfield, Reading RG7 6HL
From Mr Owen Brazell
After reading Martin Mobberley's comments in the February Journal (106(1), 10) I felt I had to reply. George Sallit, whom I know well, is an experienced amateur astronomer and found himself a victim of circumstances. He did not try to publicise this observation himself but the ball was set in motion by another member of the Reading AS who has a slot on Radio Berkshire and mentioned George's observation. The local radio station then approached George for comment and the whole thing snowballed from there.
Although one respects the work of Brian Manning and others in the search for asteroids, in general the coverage of this event was relatively reasoned from the media and gave some indication of what is possible with modern amateur equipment. There is an arrogance amongst a sector of the amateur community which seeks to denigrate work from outside their group. I understand that Guy Hurst does get bombarded with this kind of observation but as he will be the first to admit, getting somebody started is the most important thing. One has to realise that dealing with the media is not the easiest thing, particularly when one is inexperienced.
Owen Brazell
12 Burton Close, Windlesham, Surrey GU20 6QJ
From Mr R. W. Arbour
The letter headed 'Planet Sallit' by Martin Mobberley in the February Journal was misleading and unfair to Mr Sallit.
This was a discovery and most likely an asteroid, but unlike supernovae, novae and comets, a single night's observations do not qualify as an official IAU discovery. To say that no-one can find it again is untrue, it may be 're-discovered' and traced back to Mr Sallit's object, providing a valuable extension to an observable arc.
Not many amateurs understand the circumstances by which an observer can qualify as the discoverer of such an object. Below is correspondence which I have received from Dr Brian Marsden of the Minor Planet Center to clarify the situation:
'To qualify for an MPC provisional designation, you should perform astrometry on at least two nights. That is of course not enough for a general orbit, but it does enable us to check conveniently for possible identifications.
'For an orbit, you should plan to do more astrometry on two or more nearby nights later on. Some people go after the object night after night, but it is the total length of time between first and last observation that best determines the orbit – provided you do have that second night both ends, so that you can be sure that all the observations do belong to the same object. 'Later on' will probably mean later in the dark run – but try again two nights next month, and the month after that.
'The next step is linkage to another opposition. With a very long initial arc, this can be done by design. Generally however, except for very faint objects, we can find past pairs of nights (and single nights) in the record. The (combined) discoverer is then the person who discovers the object at the earliest opposition at which a useful orbit is computed – useful in that it leads to the identification.
'There is then a deliberate attempt to improve the orbit from observations at further oppositions (usually four; sometimes more; occasionally three), and when we are satisfied we can make accurate future predictions, the object qualifies for a permanent number. After that, the discoverer has the privilege of proposing a name, which is subject to approval by the IAU.'
Ron Arbour
Pennell Observatory, 29 Wrights Way, South Wonston, Hants. SO21 3HE
From Dr A. K. Welch
The recent article and correspondence on daylight viewing of Venus reminds me of a day over 35 years ago when scores, if not hundreds, of holidaymakers achieved this feat.
In late June 1959 I was on holiday in Newquay, Cornwall and was aware before the trip that Venus would be ideally placed for daytime sighting. Reference to my 1959 BAA Handbook reveals that Venus was at greatest elongation (45°E) on June 23 and brightest (mag –4.2) on July 26. It was early afternoon with the Sun almost at its highest and brightest. The deckchair must have been at a convenient angle because Venus was soon noticed. I pointed it out to the neighbouring holidaymakers who also were able to discern the planet. Over the next few minutes an ever-growing circle of arms went aloft, like a slow concentric Mexican wave, as the instructions on where to look flowed out. Finally, it always surprises me that when Venus has been located it not only looks remarkably bright but also the eye seems easily to pick it up again even when one has looked away. Having said that I must add that this was the only time I have been able to view Venus so near mid-day, so the combination of very clear skies and the deckchair in the right notch must have been a fortuitous conjunction.
Alan K. Welch
63 Churchill Meadow, Ledbury, Herefordshire HR8 2DQ
From the Director of the Aurora Section
In a recently published book entitled The Aurora, The Mysterious Northern Lights, written by Candice Savage and published in Vancouver in 1994, the BAA is cited as the organisation dealing with auroral observations and aurora related phenomena. I am currently receiving letters from Canadian and American citizens interested in observing the aurora and passing copies of their data on to the BAA. Of all places one letter was received from a student at Fairbanks University, Alaska, which is itself a well known centre for professional auroral research.
We already have some excellent aurora and NLC observers in North America, the most well known being Jay Brausch (1993 Merlin Medallist), of Glen Ullin, North Dakota, whose prodigious output of auroral reports and photographs of the mid-latitude events is the best on our books world wide.
It is a source of wonder to us in the Aurora Section that in a land mass the size of North America, so well placed for the observation of the aurora, there is no organisation so far as we know that coordinates observers, receipt of data and publication of reports. In fact, North American observers themselves not having found such an organisation have contacted the BAA and submitted their data to us. Attempts on our part to interest people in setting up such an organisation have come to nothing. In contrast Bob Evans and his team in New Zealand have evolved an excellent organisation monitoring observations in the Southern hemisphere.
There is however a team in Canada which monitors NLC led by Mark Zalcik of Edmonton and they are doing a good job.
Somebody once made the comment that Americans held star parties but British amateurs observed. True or not, it would seem that serious aurora observers have a home for their work only in the BAA. I would hope that some North American might take up this challenge and form an aurora observing network covering the USA and Canada. Britain may have lost the American colonies but it would seem we have retained the aurora.
R. J. Livesey
Flat 1/2, East Parkside, Edinburgh EH16 5XJ
From Dr M. J. Le Bas
The letter by R. L. Stratford (J. Br. Astron. Assoc., 105(6), 322) cannot go unanswered. The notion that the Precambrian outcrops at Charnwood Forest mark an impact structure is unfounded. He or she states that there are no reports of shatter cones or high-pressure shock structures within the quartz of the area; that is correct and there is none. Nor has Charnwood ever been so deeply buried as to escape any shock effect from impact. How thick any Lower Palaeozoic cover may have been over Charnwood is not known, but there is no evidence for any great thickness. Nor is there evidence for severe erosion during the Permian as suggested; the Permian was a period of deposition of limestones and evaporites. There is no circular structure centred 4km northwest of Markfield as proposed. A close look at the 1:50,000 geological map (sheet 155, Coalville) would have shown that the structure of the Precambrian rocks is that of an anticline plunging gently southeastward with its NW–SE axis some 4km northeast of Markfield, which is rather different from that claimed in the letter. The age of uplift of Charnwood was Lower Palaeozoic, probably Silurian.
It is equally difficult to envisage any impact structures within the uplifted coal measures around the Ashby area (the South Derbyshire Coalfield). The structure is that of post-Carboniferous anticlinal uplift (of which there are many other examples in Britain) followed by local basin inversion in Triassic times (again a not uncommon tectonic phenomenon) and burial by Triassic sediments. The structure is descrived in detail in the BGS memoir for sheet 155, Geology of the country around Coalville by B. G. Worssam and R. A. Old (1988). Were this in any way related to impact, the evidence of diaplectic minerals and shock metamorphic structures would be all too marked; there is none.
M. J. Le Bas
Department of Geology, Leicester University, Leicester LE1 7RH
From Mr Patrick Poitevin
For the forthcoming eclipse of 1997 March 9, I am gathering some information on cold observations. Maybe this resumé is also of interest to you.
Q: How do you keep electrostatic discharge from occurring when advancing a 35mm camera in the cold?
A: Several alternatives:
Q: What method can you use to keep batteries from losing charge?
Q: What method can you use to keep video tape and VCRs from freezing?
Patrick Poitevin
Eclipse Section, VVS Belgium, Pulsebaan 16, 2275 Lille–Wechelderzande, Belgium
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