Mircea

Last night I made variable star observations : RR Leo, R Leo, R CrB, R Boo and RX Boo. RR Leo is new to me in more ways. It is the first variable star for which I had to use pretty high magnification ( 176x) for comparison on my 200mm Dobsonian. Also the magnitude of the star itself was low, I reported m=10,6. The Moon hindered me a lot, the dim star was hard to find on a bright sky. I used the 200mm Dobsonian also on RX Boo. The other three stars were observed with the Aculon 10x50mm binocular. At the start of the session I checked the collimation by splitting the stars Nu Aur / H 5 90 , 56'' separation but stars are 7.4 magnitudes apart , Bu 1053 , separation 1.9'' and STF 799 , separation 0.7''. Mircea

Speaking about the benefits to keep long time records ... From 1990 up until 2011, I kept hand written logs. But I started the electronic ones since. Regarding the stars discussed above, this is what I found in my ''archives'' I maintain, as detailed I can: - I first split Tegmine as triple star on April 10, 2013 with the 125mm Dobsonian. I already mentioned this on page 2 of this thread. This is in line with the experience of other observers. - Nu Sco was split as a ''double - double'' star on June 18, 2011 with the same reflector. I need to mention I live at 46 degrees latitude. In the Summer there is a short window of time when there are chances to split this pretty difficult multiple star. About splitting Tegmine AB when will be at 0,6'' separation, I'm not afraid. My 250mm Dobsonian is fully and proved capable of doing that. Just I never heard of an astronomer splitting such tight double stars at the age of 90. What I am suppossed to have in 20 years from now ... Mircea

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

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

OMG, what I have done !? It is not my fault, it is the fault of Tegmine who is only a miniature of Beta Mon ...

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

And Albireo not Alberio ...

Sunshine Thank you for clarifying that, I hope I did not over reacted. Regards, Mircea

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

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

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

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

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

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

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