markse68 Posted December 31, 2022 Share Posted December 31, 2022 (edited) Been having a google and found that in the year of 1896 Mars was 17" at opposition and of very favourable altitude- just like today! 1896 was right in the middle of all the Lowell Mars canals "discoveries" so an interesting time at the forefront of planetary observational science. The observation reports are fascinating https://www.jstor.org/stable/40670965?seq=1#metadata_info_tab_contents Lowell: https://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1900AnLow...2..205L&db_key=AST&page_ind=0&data_type=GIF&type=SCREEN_VIEW&classic=YES BAA Mars Section 1896 https://britastro.org/wp-content/plugins/baa-frontend-tweaks/baa-check-file.php?filename=sites/1896 Final Report.pdf Lots of talk of canals 😄. Interesting section on "Projections from the limb" which I noticed in images and at the eyepiece above the N polar cap- a distinct bulge in the outline of the disk! Also they make an interesting comment about the ideal optimal telescope for Mars (presumably at 17" disk size )- it should be 9.25" aperture- no more and no less! haha! These facts should be borne in mind by planetary observers! Mark Edited December 31, 2022 by markse68 10 2 Link to comment Share on other sites More sharing options...
Froeng Posted January 7, 2023 Share Posted January 7, 2023 (edited) Fascinating stuff, really! The report from the Lowell observation in Mexico are interesting. I still cannot get my head around how all these professional observers thought they saw canals on Mars. The report has lots of sketches, some of which show canals cutting straight through Syrtis Mayor and other features… Thank you for sharing these! Edited January 7, 2023 by Froeng 2 Link to comment Share on other sites More sharing options...
markse68 Posted January 7, 2023 Author Share Posted January 7, 2023 (edited) It is fascinating isn’t it! Wiki has a page on it. https://en.m.wikipedia.org/wiki/Martian_canals This is an interesting contemporary report from Leo Brenner who went to visit Lowell and compared what they saw- perhaps Lowell had a sight defect that caused him to see double details which could be interpreted as channels rather than edges? : https://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1896JBAA....6..266B&db_key=AST&page_ind=2&plate_select=NO&data_type=GIF&type=SCREEN_GIF&classic=YES But i guess auto suggestion (like seeing faces in clouds) combined with strong competition between observers, canal building here on earth all contributed to the mass hallucinations Mark Edited January 7, 2023 by markse68 3 Link to comment Share on other sites More sharing options...
mikeDnight Posted January 7, 2023 Share Posted January 7, 2023 (edited) Even though many observers saw canals, the Interpretation of what they saw varied quite a bit. Lowel was convinced they were a product of intelligent design, where as Schiaparelli did not. During the 2003 apparition of Mars, I made many observational drawings of Mars using a high quality 5" refractor, and to my horror at the time, I saw and drew some of the presumed canali recorded by Schiaparelli. On several occasions when there were fleeting moments of truly perfect seeing, the surface of the planet presented a fractured egg shell appearance. Unfortunately such moments were far too brief for me to record the effect in a sketch however. Perhaps what I was actually seeing were the boundaries where surface tonal differences met. The planet was 25 arc seconds in diameter in 2003 and high in the sky, which allowed for truly awesome views, but the moment when I realised I was seeing canals really troubled me at first. I'm not so troubled these days as I've learned they are well established visual features that appear again and again. The two pic's below are af Mars globes I made from observational sketches made using a high quality 4" refractor. The smaller globe was made in 2016 when Mars from the UK was very low and bouncing off the rooftops from my observing site. Despite the low altitude I was able to make more than 30 detailed drawings of the disc. The larger globe is from observations made throughout the 2020 apparition. Both show several established linear features linked to the canal hypothesis. The canals extending from Sinus Meridiani (Dawes Fork Bay) are named Hiddekel (left) and Gehon (right); also from Margaretifer Sinus extending northward is the Indus canal creating a visual link to Mare Acidalium. [[[ Note the globes present a mirror diagonal view as seen through a refractor using a prism or mirror diagonal]]] The glob pic's showing Solis Lacus (The Eye of Mars) to the lower left, shows two canals within the darker boundary and radiating out from the dark central region. These are named Nectar ( horizontal) and Ambrosia (vertical). Reassuringly I'm not alone in being a modern day visual observer who has seen and recorded these features, so I know I'm not completely nuts. In fact if you look at the aspect of the globe showing Olympus Mons as a white cloud covered spot, its not hard to imagine how the subtle though complex linear shadings could be mistaken for channels seen by Schiaparelli. This a a great book on the subject: Edited January 7, 2023 by mikeDnight 9 Link to comment Share on other sites More sharing options...
josefk Posted January 8, 2023 Share Posted January 8, 2023 (edited) Fascinating read this morning so thanks for the links to those articles @markse68. I do love the transfer of your sketches to globes @mikeDnight what a brilliant way to record and demonstrate the observation experience. Hats off to you! Edited January 8, 2023 by josefk 3 Link to comment Share on other sites More sharing options...
Froeng Posted January 8, 2023 Share Posted January 8, 2023 I agree - those Mars globes are incredible! Link to comment Share on other sites More sharing options...
markse68 Posted January 8, 2023 Author Share Posted January 8, 2023 Yes your globes are lovely things Mike- how did you make them? Interesting you have seen the canals too- maybe it’s a refractor thing Will have to try to find a copy of that book- it’s all very interesting Mark 2 Link to comment Share on other sites More sharing options...
mikeDnight Posted January 8, 2023 Share Posted January 8, 2023 8 hours ago, markse68 said: Yes your globes are lovely things Mike- how did you make them? Interesting you have seen the canals too- maybe it’s a refractor thing Will have to try to find a copy of that book- it’s all very interesting Mark Thanks Mark, I'm not sure if it's a refractor thing as I don't often observe with reflectors. I did however have a 200mm F6 mounted alongside my FC100DZ for a while back in 2020, and have attached a sketch of Mars made with the 200mm and one with the FC100 made close together. To me they are very similar in the amount of visible detail with the 200mm showing a bit more detail, but the 100mm showing the albedo features with a bit more intensity. Both show Syrtis Major split and tailing off in oposite directions in the south. I'm not sure if these tails are related to any supposed canals, but the fact both scopes were so close in the detail they showed, I'm pretty certain reflector users won't have to rush out and buy a refractor. The globes are made from stainless steel balls of the kind used as garden ornaments. I spray painted the globes with a mat spray paint, then divided the globes into quadrants and divided the equator into degrees. I used the thirty plus observational sketches for each aparition as as my reference. Using a soft graphite applied using cotton ear buds, it was relatively easy to place the albedo features in their relative positions with reasonable accuracy. A putty eraser was used to lift graphite off the globes to produce a mottling effect and to sharpen edges. Once completed the globes were sprayed several times with gloss lacquer. The most difficult part was drilling through the steel globes to enable their being mounted to a base on which they can rotate. 6 Link to comment Share on other sites More sharing options...
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