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It would be worthwhile measuring the focal length , the original Mond Zeiss 7 inch was f/7. Also have a look at the 7 inch Zeiss triplet lens that we sent back to NLO (the one Harold Ridley passed on to Glyn) and see if they are similar.
The main fact to find out is whether the optical design of the 7 inch you have found is a Petzval doublet or a Zeiss triplet(telephoto) . The original Zeiss triplet on the Mond was a triplet of f/7. Cooke mounted the Zeiss lenses onto the Mond astrograph for Robert Mond.I would look for some markings on the lens cell/housing which may show it to be a Zeiss.
Denis
Write to The Antique Telescope Forum, there ar lots of experts involved in that group who will be able to give you the information you need.
Hi David,
The large lens (7 inch) may well be the original 7 inch f/7 Zeiss astrograph lens that was missing from the Mond when Glyn Marsh and I rescued the instrument from NLO. The 7 inch lens was missing and was not amongst the other astrographic lenses we collected and are now back at NLO with the Cooke/Mond Astrographis mount. The 7 inch that you now have was one that Harold Ridley passed on to Glyn and did not come originally from the NLO.The lens design of the lens you ahve just found may be that of Petzval Doublet. The small 3 inch refractor looks like a guide telescope with a sliding plate that carries the eyepeice and diagaonal across the FOV to allow the observer to selected a guide star. I would guess that both instrument s were part of the original Mond Astrograph or from another of the large telescopes there at NLO. I have taken the liberty of posting your message and images on the Antique Telescope Forum to see if anyone ther can more positivley identify these instruments. Denis Buczynski
Hi Alex,
Is the shadow track well established. I see that I will be outside the track at Tarbatness. Is it still worth while me observing this event?
Denis
Tarbatness observing statistics 2021 observations on nights when ccd comet astrometry and photometry was undertaken; Jan 19, Feb16,Mar12,Apr10,May4,Aug7,Sept10,Oct12,Nov9,Dec17. Total=116 nights This excludes any nights from mid May until mid August when observing is not possible at this lattitude 58d N due to all night twilight. Observations of other objects Novae, Supernovae, and other transients were made on nights when CCD comet imaging was taking place.Some deep sky ojects were imaged in colour. In the winter skies displays of Aurora were recorded. In the Summer skies displays of NLC were recorded. Meteor count on two cameras 12mm camera 2328, 3.8mmcamera 1844 Cameras are turned off from mid May to mid August due to all night twilight. All in all it was decentish observing year here at Tarbatness, I am not sure I could have done more.
You may want to watch the talk I gave at the BAA Comet section meeting about comet magnitudes which mentions “the Sidgwick method. Here is the youtube link;
https://www.youtube.com/watch?v=S8I3TdaUjxY&list=PLzBTybazXT40groFEC3zg4uVLFFGdApQL&index=4
Hello David.
This sounds like a very intersting project/programme for someone. I hope the Zeiss Blink Comparator and the Hilger Plate measuring machine that I gave to NLO a couple of years ago (part of the return of the Mond Astrograph after Glyn Marsh’s untimely passing) will be of use in this project.
Hi Jeremy Looking at the Catalogue of Meteorites by G.T.Prior and Max Hay 1953 (Harold Ridley book) I see that the Gibeon Meteorite fell in SW Africa at Great Namaqualand and the finds are well documented in this book pages 131 and 132. Many large and small masses were found over wide area and 51 large masses over 15 tons have been recovered. These specimens have found between 1838 and 1910. So it is likely that the specimen you saw at Tatton Park could well be one of those.It was classified as Iron fine octahedrite. A 1.5 lb piece was sold at Christies in February 2021 for 12.500 dollars, So the 325 lb specimen at Tatton must worth a few quid! Christies gives this description :
Details
Like most iron meteorites, Gibeon meteorites formed 4.5 billion years ago within the molten core of an asteroid whose shattered remains are part of the asteroid belt. After wandering through interplanetary space, several thousand years ago the Gibeon mass slammed into Earth’s atmosphere where it exploded and rained down over what is now the Kalahari Desert in Namibia. In previous generations, indigenous tribesmen recovered small meteorite fragments at or near the surface and fashioned them into spear points and other tools. This specimen was recovered with the aid of a metal detector. Gibeon meteorites were not known to westerners until 1836. They formed deep in the iron core of an asteroid that resided between Mars and Jupiter.Hi Richard, I am sure that this Mike Peel is not the Mike Peel you are referrring to. I knew Mike Peel well, he was the Science librarian at the University of Central Lancashire and a variable star observer who made photoelectric measures with an IP21 photometer (you will remember those devices I expect!) with his home built 8 inch reflector. His main interest was in T Cor Bor using period analysis to try and to find when its outbursts would occur. He is much older than the astronomer in the link in Jeremy’s post, he will be in his 70’s I expect now.I hope this helps and brings to mind a past member who was very active within the VSS in the 1970-80s.
Some views throughout here at Tarbatness both NE and 102mm Mak+solar film. Cloud was thick at times but more attenuated after maximum eclipse. Clear, sunny and warm now! Liz watched the event NE via reflection from the glass coffee table with the sun behind thin cloud.So simple, looking down rather than up and without neck strain.
Denis Buczynski (Tarbatness still in the UK!)
I knew Sally when she lived in Windermere Cumbria. She was a keen visual lunar and planetary observer. A very fine person and so likeable. I helped set up the Elliot Merlin 12 inch reflector ( on loan from the BAA) at her home in Windermere in the 1990’s. She used it regularly and contributed many observations to the BAA observing sections. Picture of the Elloit Merlin telescope is attached. Unfortunately this fine example of a Calver refector so kindly bequethed to the BAA is now no longer usable having passed through the “care” of the last BAA Instrument Curator after it was returned to the BAA after Sally had finished using it. Picture of the telescope last time it was seen is attached.
Here is my image of this object from last night 20210402 00:29 UT with astrometry of what I assume to be the SN.There are lots of knots in the galaxy arm and i have to use a small 3 pixel radius aperture to get a measurement.
Denis Buczynski I81
1) Where did this object originally form and where has it resided in the Solar System since its formation 4.6 Billion years ago?
2) Has its original orbit(within the asteroid belt?) around the Sun been constantly altered by planetary perturbations etc?
3) What was its present orbit and period around the Sun prior to impact with the Earth?
4)How has its orbit evolved to put it on an Earth crossing orbit.
5) Have there been previous near misses in the past?
Signed INTERESTED and CURIOUS of TARBATNESSHello all, My main observing programme is astometry and monitoring of comets. The year is divided into 3 parts for me here in Tarbatness Highland Scotland at 59d N latitude. The fisrt is the months from Jan-May when observing is possible ina dark sky. The second is frOm mid May-mid August when no observing is possible due to all night bright twilight, Then third from mid August-December when observing is possible in a dark sky. During the second period of the year only observations of NLC are possible. Vitually no observations were made of the bright naked eye comet C/2020F3 NEOWISE in June/July due to the twlight conditions. Contrary to other parts of the UK which saw good spring and summer conditions that allowed pleasant observing, here in Highland Scotland the weather was fairly grey, overcast and cool. However I was able to observe on 106 nights when comet imaging took place and I included 87 reports of photometry of comet 29p a target for the 29P MISSION progamme run by Richard Miles for the BAA Comet Section. My two meteor cameras were operating through the year apart form the summer shutdown months and around 2000 meteors were captured on each camera and reported to NEMOTODE. The year was comparable to previous years for observing.
