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Mircea

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Everything posted by Mircea

  1. Ian Very good points made by you, that is a concentrated history of double star astronomy ! I agree with all but one: Galileo. Unlike general wisdom, my opinion is that Galileo was a genius scientist ( '' learned'' or similar term in those times ) but not a great observer. He observed many times in Orion but didn't noticed the Great Nebula M42. It was Claude Fabry de Peiresc the first who took notice of this huge object, visible with naked eyes. Anyway, it was not Benedetto Castellani, one disciple of Galileo, the one who made the first discovery of a double star by observing Mizar ? I know that Galileo observed himself Theta 1 in Orion as triple star , there is a sketch in his papers. But he swept the discoveries of double stars under the rug because apparently those were disproving the Heliocentric theory. Not a very honest attitude from a scientist. Mircea
  2. Ian Thank you for quoting Couteau and Argyle about resolving down to half the Rayleigh Criterion. I'm convinced they are right. I searched in my observation log for Tegmine. Up until 2020 I found the observations in the attachment. On March 13, 2017, I resolved Tegmine with my 90x600mm refractor. AB was not split but the Airy discs of the three stars were clearly seen. The Dawes Criterion for 90mm aperture is 1.29'', the separation of AB at Tegmine was 1.114'' at the time of the observation but I made a mistake of no material consequences by noting 1.14''. A bit of history. The larger AB,C pair of STF 1196, now of 6'' separation, was discovered by Christian Mayer before 1779. Christian Mayer is the founder of double star astronomy not William Herschel. He published the first catalog of double stars in the History of Astronomy in 1779. The main instrument of Mayer was the wall quadrant of Mannheim Observatory , made by J. Bird. The optical part of the Bird quadrant is a Dollond refractor of three inch and two line aperture and eight feet focus. The Mayer Catalog contained 72 stars, the bulk of which were discovered by him. Star Mayer 22 is Zeta Cnc or STF AB,C with a separation of 7.7'' at the time of discovery. I see on StelleDoppie the year of discovery of STF 1196 being 1825. From this and from the STF symbol ( mnemonic: Struve The Father ) , I infer that AB was discovered by Friedrich Georg Wilhelm Struve, also known as Vasily Yakovlevich Struve. Between 1820 and 1839 he was professor at the University of Tartu. The famous Fraunhofer 9.5'' refractor arrived at Dorpat on November 1824. So, I guess STF 1196 AB was discovered in 1825 at the Dorpat Observatory, by Struve The Father, with the 9.5'' refractor. But I believe we should also remember Christian Mayer, the discoverer of AB,C pair as part to the story. Mircea
  3. OMG, what I have done !? It is not my fault, it is the fault of Tegmine who is only a miniature of Beta Mon ...
  4. In my understanding, what Rayleigh and Dawes set are criteria not limits. Those numbers are not like crossing a border or turning a switch. A good telescope will continue to show the Airy discs of binary stars much bellow the values suggested by Dawes or Rayleigh criteria. As an example, on July 30, 2020, I was lucky enough to see the one third overlapped Airy discs of STF 2215 ( mag. 6 + mag. 6.9, separation 0.44'') with my 200mm F/ 6.16 Dobsonian. The importance of splitting of the components of double stars is much overrated. That is important if one is measuring using a filar micrometer. Because you don't know where to position the threads on an elongated image to be sure you bisect through the center of the Airy discs. The famous black strip of sky seen with split double stars is a guarantee you set the threads of the micrometer to the right place in order to obtain a valid result. For us, visual observers of double stars it is vain to struggle for splitting. If one obtain an image like that called ''resolved'' in David Knisely's diagram, we are good. On the topic: I first split Tegmine as a triple star with my 125mm Newtonian on April 10, 2013. This should be close enough to a four inch refractor which I don't have. Clear sky, Mircea
  5. Sunshine Thank you for clarifying that, I hope I did not over reacted. Regards, Mircea
  6. Bortle is the name of a person who tried to help a bit amateur astronomers. I respect that and I'm grateful to him for that. Mircea
  7. Not speaking about the fact that in my couple of observations of December and January, Betelgeus was stagnant at magnitude 0.5. Friday, on February 16, the magnitude of Betegeus increased to 0.6 magnitude. So the brightness decreased a bit. Right on time to ''honor'' the said feed ! Mircea
  8. Nobody asked my opinion on this matter but willy-nilly you will find it here. I don't have proofs because I'm not a player in the field of search of Planet 9. But I spent about two month reading, thinking and writing about Chad Trujillo, Scott Sheppard, Konstantin Batygin, Mike Brown, Sedna, Goblin, clusterig, Farout, Farfarout, Antranik Sefilian, J.R. Touma and so on. It was quite natural to gain an opinion, a ''belief'' about Pluto / Pluton. To cut a long story short, I think Mustil is right. Pluto is a complex body with solid core, liquid oceans , atmosphere, seasons, climates with weathering, geological life (earthquakes, earth slides) , five satellites ... because it is a captured PLANET. Hints : - the very eccentric orbit of Pluto / Pluton - the 120 degree tilt of his axis related to the orbit plane, -the tilt of the orbit of Pluto relative to Ecliptic - the fact that is even crossing the orbit of Neptune - the retrograde motion of Triton is also pointing toward a cataclysmic encounter , could be the same Just have a look at some diagrams here. You will see the position of the axis of Pluto and the shape and tilt of his orbit at ''The Basics'' here: https://pluto.jhuapl.edu/Pluto/The-Pluto-System.php?link=Phases-and-Seasons To me all this hints are supporting the caption hypothesis. It is possible that we have a guest body from outside the Solar System which can be studied. But no, we will not do that because of the laughable criteria '' he did not cleaned his orbit ''. ( I really don't care about the bla-bla regarding the demotion of Pluto. Demoted or not by meaningless humanity , a celestial body keep looking the same. I'm disgusted that astronomers at IAU are doing politics not Science any more. I can prove it with a print screen of the Inbox of our Astronomy club. It is full with invitations to IAU zoom meetings to discuss things, mostly political, having nothing to do with Stargazing. And by the way , the famous demotion was voted by ''the majority'' of the five percent of membership who attended that meeting of IAU. ) Mircea
  9. The 9th planet probably don't exist. In 2019 I wrote an article published in the Romanian astronomical magazine ''Pasi spre infinit''. The article contain my survey of the status of the search and research for Planet 9, up to 2019. One of the results was a bit unexpected. Virgil Scurtu , noted amateur astronomer in our country and author of astronomical books, sent me his view on the issue of Planet 9. He expressed some criteria regarding the birth of a planet in the outskirts of the Solar System. Those criteria do not forbid the birth of a planet in those conditions but is making the process highly unlikely. The possibility left open is the caption process proposed by Alexander Mustil from Lund University. According to Mustil, if Planet 9 exist, it may be a planet captured by the Sun while still being in the ''maternal'' star cluster. This hypothesis is really troubling because it would make Planet 9 the most interesting object to study. No, not for aliens but because it would be the first massive object born outside the Solar System and in our reach. In attachment is the page of the article containing ''the criteria of Scurtu'', numbered from (1) to (4). The article is in Romanian language and I didn't wrote an update or a translation. It was mentioned the names of Percival Lowell and Clyde Tombaugh, related to Pluto/ Pluton in Romanic languages. I would like only to add that the quest for Planet 9 was started by a hypothesis of French astronomer Camille Flammarion. Mircea
  10. josephk You are right, it is a chore, a harsh chore ! I will take care never fall in this position again. It is true I had some health issues during this time but ultimately this is only an excuse. Things are looking good. It is worth keeping an up-to-date observation log. Working to update my Excel version, I found today that on June 29 , 2022, I observed with the 250mm Dobsonian NGC 6572, NGC 6369 and NGC 6356. The last two, are planetary nebulae in Ophiucus and both are H400 objects. I hope to find some more ... And when weather will allow, let's do some more observations. Mircea
  11. I logged 188 objects of Herschel 400 List. But I did not updated my Excel log book since 30 January 2020. I always take scrupulous written notes , sometimes with drawings, so the observations are logged , they need to be processed. A quick look convinced me that I am for sure at over 200 objects. I'm saying this because Silver Coin Galaxy is not ticked but was many times observed, the objects in Cetus not ticked although I observed them last Autumn. And every Spring I live more in the Virgo - Coma galaxy cluster than at home. I'm doing an update of my Excel observation log, currently being at August 2022. Soon I will have the actual ''picture''. 17 Messier objects are also Herschel 400 objects. Those are included in my 188 logged H 400 objects. Rarely I do purposed H 400 observations. When I do, I use as resource the '' Herschel 400 Observing Guide '' by Steve O'Meara. The 188 objects I mentioned above are mainly a spin-off of my double star observations. I use to observe one by one all the double/ multiple stars from a chart in CDSA. Well, if a DSO it happen ''to be in my way'', be sure I will not avoid it. Mircea
  12. Here in Arad, in the country of Romanistan , the politicians decided to install lights under every tree. If not, how will know the rain where to fall ? Also light bulbs are going to be installed in every toilet for a double benefit. Every poop to be able to stay and take part to the political life of the establishment as much as possible. This is constantly increasing the solidarity within political class. Second, without light, how will know the flushing water where is up and where is down ? But water going up or down is really not important. Important is the water should avoid at any cost to go ... Lord forbid ... to the far right. As a result of such wisdom, largely supported by the even deeper wise electing people, one should carefully check the clock to know if it is day or night. Mircea
  13. You hit the nail on the head. If there will be stars visible around the DSO, the RACI will make them visible ... maybe . If no stars are visible than one need a new army. A good option seems to be Go To telescopes. Something I forget to underline in the previous post. It is obvious but the RACI finder is showing you the sky ''as it is''. It is like navigating muddy waters or flying over misty mountains. In such extreme conditions you need the best and logical gear , you don't have time and no needing to invert, to count, to reverse, to imagine. I know, when observing I am safe physically all the time . But something much more subtle is at stake. The damages to the pleasure of observing are intelectual but I tell you, these are hurting and hurting a lot. Mircea
  14. SwiMatt I have four reflectors ( 125mm Dob, 148mm Newtonian on pipe-mount, 200mm Dob, 250mm Dob). ( One 76mm is under refurbishment and one 100mm is under construction. And no more reflectors ... if you are prepared to believe me. ) I use separate brackets for each finder. I don't have equatorial mounting so their position follow the same rule. Axially, the position of the RDF is the upper most possible toward the mouth of the OTA. This is because I'm old and to see things better I tend to move them away the most possible. Radially, the RDF is on crest of the OTA. Then I take the RACI and, by trial and error, I'm searching that position where I can look either in the finder, either in the main eyepiece while sitting on the observation chair. The ten inch Dobsonian is commercial, it came with Radiant finder, similar to Telrad. It will be removed and replaced this year with an RDF, so also this telescope will follow same scheme. I understand the issues other amateurs are having according to local circumstances. I use this method learned from the guide of Urban Astronomy of Rod Mollise because is working for me. Sure, it is not a panacea , it is just a good method where fit. I was thinking this way: if GrumpiusMaximus is seeing stars to point the RDF, maybe the method will work also for him. However, I don't use the method on my small refractors ( more 60mm, one 90mm) or on ETX 90mm. There, I use an RDF or a conventional finder. The finders are at the lower end of the tube, is loosing much of the apeal. Aaaand .... two 8x50mm RACI finders and that 60mm RACI for the bigger Dob, took out enough money from my pocket, I stop the madness here. Mircea
  15. I don't think an elbow RDF will be helpful. After years of Urban Astronomy, I suggest the use of an RDF and a finder, I prefer and use RACI. Imagine you are an astronomical guerilla fighter. The RDF is the chopper which will drop you close to the point of contact with the enemy. RACI + low magnification ocular are your snippers who will do the accurate hit. In other words I don't ask and don't expect the RDF to bring me to the target, only close to it. It is a very important tool because is orienting the telescope toward that part of the sky where the star asterisms in the finder could be recognised. But the RDF is best doing this when looking through it and besides it. The red dot became part of the asterism I see on the sky and forming triangles or other geometrical figures. The place where to put the red dot I estimate it according to the atlas and is hopefully coincident with the target. ( I wish ... ) But on the city sky, this asterism is usually quite large, made by bright naked eyes stars, located faraway. This is why I don't have high expectations of accuracy from RDF. Then it came the RACI and the low magnifying ocular of the telescope to finish the job. Happy New Years to All, Mircea
  16. Regarding green stars : last time when observed , I saw Beta Lib / Zubeneschamali as blueish with binoculars. But when I first searched for it, I used my 60mm refractor and the 125mm reflector and I saw it greenish. But the green color of Bet Lib was best seen with my 15mm F/22 singlet refractor, having a magnification of 9x, specially built for reenactment observations. In that tiny aperture, Zubeneschamali was quite green. I don't think the color has to do with the lens being non-achromatic. Please see the extract below. ( The French astronomer Nicolas Louis de Lacaille used a 15mm singlet refractor to chart the Southern sky from Cape of Good Hope. Actually his 15mm singlet refractor was the finder of his bigger telescope so I guess his was made of brass not cardboard like mine. 😄) Just as a curiosity, you can see my smallest telescope in the attachments together with an extract from my observation log regarding Bet Lib. I just learned Zubeneschamali is the double star RBR 7 but the informations on StelleDoppie are a bit confusing to me. The primary star is quoted as magnitude 7.5. But how can this be when Bet Lib is of magnitude 2.6 !? Anyway, the companion of magnitude 16.5 cannot be reached by the 250mm Dobsonian - my light bucket. tico Thank you for the picture of S.W. Burnham ! This name, shortened as ''Bu'' is giving me goosebumps when met on CDSA maps. It is like being again a kid and the most famous bully of our neighborhood is crossing my way. Probably he will beat me again but maybe this time I will trick him, give him a good slap and than run away. To be honest, I succeeded twenty, maybe thirty times to snatch the laurel wreath but most of the time not. What's disturbing is that at each such encounter, I feel an uncontrollable urge to try my luck. Bu 385 was one of those rare moments of glory and is related to the topic. The primary A is a beautiful azure , B is bone white with a very slight yellow patina while C and D are neutral white. Mircea
  17. Hey, I don't know why but I like very much this topic ! 😍😍😍 Thank you badhex and I wish you clear sky for good duble star observations ! Thank you for sharing your observation notes. When using the 125mm reflector, the trick working well for me with companion C of Sigma Ori is to look at companion D, the first to the East of primary star. This way I activate my averted vision. Zermelo I fully agree with you, 52 Ori is difficult. I like also 32 Ori and I agree also about these. In spite of larger separation, there were nights when 52 Ori was split but 32 Ori just resolved. I remember once noticing another, much dimmer double star in the same field - or very close - to 52 Ori. But I can't find yet the report. Mircea
  18. lunator Thank you for your comment and for the formula which is new to me. I will do the calculations for the other telescopes I have, I'm very curious. Mircea
  19. The60mmKid Very good points. I highlighted the last one because I can provide some examples. I already mentioned the companion of Rigel. The main star is very bright compared to the companion, this is the main difficulty with this double star. We had an action on the Romanian ''astronomy.ro'' forum regarding the visibility of the companion of Rigel. Our action confirmed the statement made by William Kitchiner that Rigel can be splitted with a telescope as small as 1 3/4 inch or 45mm. My colleague Iulian saw the companion of Rigel with a 45mm refractor on February 1, 2018 while I succeeded on February 5. Iulian used a genuine 45mm refractor, I stopped down my 60mm refractor. It was really interesting, the best image of splitted Rigel was provided in my telescope by the 92x magnification obtained with a Galilean eyepiece of -9mm focus. The color of Rigel's companion reported by me was coppery reddish. The report of Iulian can be seen at link below on page 2, my report is on page 3: https://www.astronomy.ro/forum/viewtopic.php?t=17374&postdays=0&postorder=asc&start=15 The indigo color of Rigel's companion was observed by me on February5, 2019 , with my 200mm Dobsonian, at 205x and 308x. badhex I'm very curious to read your notes about those doubles in the Lockyer's List, you will have a reader here for sure. Mircea
  20. badhex I hope my suggestion in the document attached will be not seen as a lack of modesty. I suggest to see all the six stars in what I call ''Lockyer's List''. 52 Ori is the most difficult as separation. But there are also plenty of dim companions there at Sig Ori, Lam Ori, Zet Ori. On topic : Lockyer mention the color of Alnitak stated by Struve as being ''olivaceasubrubicunda'' !!! 😍 glafnazur Thank you for confirming I used the correct word. My mother tongue is Romanian which belong to Romance languages this is why I used ''indigo''. Clear sky, Mircea Lockyer's List.pdf
  21. badhex I like double stars and everything about double stars: books, articles, magazines, journals, maps. Thank you for the very interesting and reviewed lists of double stars by Olcott. And my thanks to PJ Anway for preparing them and for sharing them. About twelve years ago I was using the book ''In Starland with a Three Inch Telescope'' as an observing guide. I used my 125mm reflector and my first 60x700mm refractor. The only issue I had was not enough accuracy of the maps. Please let me make just a comment about the list. Olcott star # 336 which is STF 795 or 52 Ori. The separation is not 1,1'' anymore. The current separation is 0,97'' , going to decrease to 0,96'' next year and so on. Since year 2020 , 52 Ori is a subarc double. Last night I struggled in vain to resolve it with my new 148mm F/5 Newtonian at 250x, the seeing was not good at all. Related to the topic : StelleDoppie , a mirror of WDS, is stating 52 Ori consisting of A5V stars. Other A stars are Vega and Fomalhaut. Well, maybe it is something wrong with me but always - this include the observation of last night - I saw 52 Ori as a deep yellow or light orange. Definitely not a sister of Vega. How do you see this wonderful double star ? However, last night I was able to split Rigel / STF 668. The main star is of blueish white color , no doubt. But what is the color of the companion ? How do you see it ? Last night the seeing was bad, I was able just to confirm the existance of a companion, flooded by the intense, pulsating light of the primary star. But in the past, in my 200mm Dobsonian, with a steady image, I saw the color of the companion as indigo. Mircea
  22. For about twenty years the 125mm F/ 6.9 reflector seen below was my main instrument. And double stars were and are my main interest. The 125mm is a very good telescope, is able to split 52 Ori and is resolving STF 2 and STF 13. I tend to agree with what was stated by James Mullaney. The colors of double stars are more vivid in this reflector than in my 250mm Dobsonian. Actually, Albireo and Almach have washed out colors in the bigger telescope. ( Which is not a telescope ''to be despised'' as Lockyer used to express himself about good telescopes. ) I use a funny method to see the colors of stars consisting in the use of a Huygens eyepiece of 16.7mm focus. Stars like Betelgeus, Pollux, Castor, Antares, Rigel, Procyon are providing quite a show ! Because of the strong spherical aberration induced by the eyepiece, the image of the star is expanding in a huge dandelion of light, radially furrowed by thin spikes of light , perpetually moving and pulsating due to turbulence. There is color to be seen also at subarc doubles. Like the orange hue of Bu 720 in Andromeda split last Summer with the 250mm Dobsonian. Clear sky, Mircea
  23. Richard My opinion is that finder may have issues at resolving double stars because it is ... too big. Why am I saying this ? I have a similar finder, branded as BTC 60x232mm. I did not try it on double stars. But the objective is less than F/4 and it use an Amici prism, not very good for higher resolution. But I have very good experiences with a 45x300mm refractor. Below, I randomly choose examples from my observation log of double star observations with this 45mm F/6.67 refractor used with a normal prism diagonal. The 45mm aperture is not an issue to split Beta Mon as triple star or Theta Ori 1 /Trapezium as four star system, Gamma Del, Alpha Her. Of course, Epsilon 1-2 Lyrae was resolved as a double star. I believe, the 60mm finder, as it is, should resolve Albireo, Theta Ser, Omicron Cyg, 16 Cyg, 61 Cyg, Beta Lyr, Psi Dra, Nu Dra, 16+17 Dra, STT 747, Mintaka, Sigma Ori as a double and many more such doubles. Please let us know your results. In the attachments we see my 45x300mm ''beer bottle'' refractor and a small part of objects/ double stars observed with it. It was my first achromat lens in a time when here in Romania there was no telescope market and achromat objectives existed only in the wet dreams of amateur astronomers. Only in 2011 I got my first astronomical 60x700mm lens, a donation from Brian Nordstrom, colleague on ''60mmtelescopeclub''. Mircea
  24. A Tele Vue Radian 3mm. It is SH, only the non-essential cardboard box is missing. It was sky tested last night by myself and my observation pal Armand, who brought it. What an amazing eyepiece ! It provide 400x on my SW Classic 250P. It split some subarc double stars right after arrival: Lambda Cyg, STT 410, STF2, Bu 720, 16 Vul. Zeta Her and Delta Cyg were also very nice and wide split. M13 and M15 were split in stars all across. Happy man here ! Mircea
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