I.S.W.A.T.I.T. by Olcott , revisited

[Mircea]

 

I am embarked to revisit ''eye at the eyepiece'' the book ''In Starland with a Three Inch Telescope'', short ''I.S.W.A.T.I.T.'', by William Tyler Olcott. 

Until now I revisited the objects of : Corona Borealis, Draco, Hercules, Lyra, Bootes, Ophiucus and Serpens, Sagitta and Delphinus, Scorpio, Ursa Minor, Aquila, Cepheus and Cygnus.

Below is my adventure of Friday, last night, in the den of the Scorpio: 

 

On Friday, July 19 this year, I observed the objects in the constellation Scorpio, according to Olcott's book I.S.W.A.A.T.I.T., pp. 32 - 33. The instrument used was my ''Ugly Duckling'' Dobsonian D=125mm F/6.9, with the Svbony 10 - 30mm zoom eyepiece and various TMB or TS Planetary eyepieces ( 5mm, 4mm, 3.2mm).

* The constellation Scorpius is, for my observations from home, a southern frontier constellation. I can't even see all of it, the M6 and M7 clusters are visible in a very short window of time along with the stars in the tail of the fiery insect. So, last night, I didn't get my hopes up, I started observing with the feeling '' come on, I have to do this one''. How far from the truth !  It's true that Olcott's list for Scorpio is short, only six stars. But what stars...  One of them is perhaps the most beautiful multiple star of the celestial sphere.

- I made a slow and tame debut with Beta Sco/ Graffias, a 14'' double that I solved in ''my observational youth'' on June 13, 2015, with my D = 45mmx300mm mini-refractor at 17x. So it's an easy double.

- Not the same can be said about the Nu Sco. It bears a worthy name for some hero from ''Star Wars'', the old series. ( Anyway, I stopped following the story long time ago, it had become boringly conformist in being nonconformist ... ).
Olcott included in his book only what is seen at Jabbah at low magnification, i.e. double H 5 6 AC, with a 4.35mv primary and a 6.6mv companion, separated by 41''.
At 87x, things got more complicated and Jabbah was seen as a triple star, with a 4.35mv primary and two companions, C and D, 2.4'' apart and 41'' from the 4.3mv primary.
At 173x, the bright star is resolved in Burnham 120 AB, separated by 1.35''.
A true celestial treasure, a necklace of astral gems, a beauty beyond compare! Oh, how dear to me is this tiny reflector, small and ugly by day, but at night it spreads its wings and becomes an astral swan carrying me on its wings through such enchanted corners of the Galaxy!

- And, thrilled by the marvelous view, I moved on to one of the next stars on the list, Xi Sco. There, after Olcott, I was to see an uneven 7" double. Indeed, a bright star with a companion at 7" was visible in the telescope field. But... what the hell... when did that happen? ... look, I took off the telescope... What am I supposed to do in the middle of the night with a decollimated telescope?
The primary star showed a serious astigmatism at 173x, obtained with the TMB Planetary 5mm eyepiece. I pointed then the telescope at other stars and, lo and behold, the astigmatism disappears. It didn't take me long to "realize" that something was wrong with the star Xi Sco. I magnified to 216x with TMB 4mm ... et voila ... this primary is double ? At 270x, obtained with TS Planetary 3.2mm, there was no doubt. Yes, Xi Sco AB is 1.08" apart.
In the telescope field, Xi Sco we see five stars: AB at 1.1''', C at 7'' and two more distant stars that actually form a separated double, STF 1999 with AB separation of 12''.
I have run out of epithets and adjectives at Nu Sco but Xi Sco seems to be, if not ''the most'', ''one of the most'' beautiful multiple stars on the starless vault. Try it for yourselves, it'll be over soon. Not the star, but the period of visibility.

- Double P. 236, 4'', I couldn't find it, neither in the sky, nor in CDSA, nor in Taki's atlas of doubles.
I set the RDF finder to the approximate location shown by Olcott on his sketch and groped around the 1/3 position between Eta Oph and Antares. The only double star that resembles Olcott's parameters ( 6,5mv+ 8mv + 4'') is the star Sh 240: 6,6mv+ 7,6mv+ 4,3''. I easily resolved this one with the Baader f= 12.5mm micrometer eyepiece at 69x. For the ''Ugly Duckling'' reflector, I haven't yet determined the value of a linear divisions, so I didn't try to measure the separation. But I tried to measure the position angle and got PA = 350*. Stelle Doppie gives PA = 253.4*, measured in 2019. An error of only 1,6* on the first try I say to be a big progress compared to the estimated accuracy of +/ - five degrees ( ten, fifteen , twenty  ... ) so far.

- I also tried a position angle measurement at Albireo where I got PA= 55*.
Stelle Doppie gives for Beta Cyg a PA= 53,9* from 2022. Error of 1.1*. The future is rosy !

- I looked again at Rho Oph that Olcott included here at Scorpio and saw four components, with AB = 3''.
C is at 151'' and D is at 156''. Another celestial beauty !

* I quickly went back to  Ursa Minor where I fallen behind on Thursday when I didn't found STT 262.  But observed Burnham 799 instead.

 Stellarium showed me at what a short distance from Burnham 799 is STT 262. I found very easily STT 262 and resolved it at 29x/ Svbony model 170 at f=30mm.

 ( End of the ''Olcott revisited'' part of the observation of last night.)

- I continued by resolving again at 173x the double Burnham 799, with a separation of 1,4''.

- In Cepheus I have resolved but not split  STF 2 and STF 13. Neither at 216x/ TMB Planetary 4mm nor at 270x/ TS Planetary 3,2mm, I didn't get the separation, only the ''eternal'' sign of Infinity. I was satisfied with that.

* I ended with the Saturn observation where at 173x, I could see very well the ring become a thick bar. To the south of the ring, a band or a shadow of the ring was visible?
Three stars could be seen to the west of Saturn, forming a sloping line. Right near the eastern ansa was Rhea. Six times the diameter of the ring to the west was Titan. Sometimes, even farther west of Titan and very, very faintly glowing was seen fluctuating, only barely visible, a very dim spot that was never visible with direct vision: Iapetus. This elusive object was seen with averted vision only, about one-third of the distance between Titan and the middle star of the three-star linear asterism in the western part of the field.

Very rich is Scorpio! Such are these mythological beasts!

Like Smaug, the Fire Dragon, the possessor of a superb hoard in Draco. Some, however, with quicker hands - like Bilbo Baggins, or eyepieces - like old Mircea who wrote this lines, dare to sneak to their treasures.

I'm attaching a picture of my beloved ''Ugly Duckling'' Dobsonian reflector, D = 125mm F/6.9, used at Scorpio.  Next year, this home-made reflector, will be thirty years old.

If the subject will trigger some interest, I will post also my next observations.

Mircea

Translated with DeepL.com (free version)

[Mircea]

Thank you Nik 271, John, JeremyS and  IB20 for the encouragement !

 

On Sunday, July 21, I continued the ''reading at the eyepiece'' of the I.S.W.A.T.I.T. book.
The telescope used was the already mentioned Dobsonian D= 125mm F/6.9 armed with the Svbony 10 -30mm zoom eyepiece and TMB Planetary eyepieces.

Canes Venatici, p. 22 -23: there are only five stars for this constellation in the table and on the map in Olcott's book.

- Cor Caroli/ Alfa CVn is a superb double star, one of the most beautiful. If I had to choose one word to describe it, it would be "elegant". One must observe it carefully, relaxed. At 87x I could already start seeing the fantastic color contrast but it was 173x when it become clearly visible: the primary is a very pure white and the companion is lilac.

- 2 CVn was easily resolved at 87x but it is worth using higher magnifications here too. At 173x the colors of the components were much better visible: the primary was a pale orange  while the companion I saw it as lavender indigo. Olcott saw it as blue.

- ''La Superba''/ Y CVn was already visible as orange in the RACI finder but much better, deeper orange-reddish color in the telescope, at 87x.

- I found with difficulty STF 1615, hidden in the haze, then resolved it without difficulty.

- 15 CVn appears in the eyepiece as a bright triple but Olcott only describes it as a double. The third bright star, visible close  at low power, does not belong to the system. Stelle Doppie however shows me that 15 CVn really is a triple. The STFA 24 double's companion should resolve into BU 608 BC with a 1.3" separation. STFA 24 or 15 CVn I can tick it off but I still wish to see BU 608. Maybe tonight ?

So, we have a short list for Canis Venatici but with three stars with very nice color contrast. Y CVn was not included in the table , only in the notes. That is however older acquaintance to me. And since April 30 is on my variable star menu.

 

Ursa Major , pag. 34 -35: Olcott lists nine double/multiple stars, of which I visited seven last night.

- 23 UMa was fairly easy to find but a bit harder to resolve, not because of the 23'' separation but because of a Delta mag = 5.5mv. Once found, I split it and then used this star to find the others in the area.

- Sigma 2 / STF 1306 was more difficult to resolve. It has a 4'' separation and Delta m = 4mv. At 87x I got nowhere, I had to use 173x, and a lot of patience but in the end I succeeded.

- Using the minimum magnification of 29x , obtained with the zoom eyepiece, I then resolved STF 1415, STF 1495, STF 1520, 65 UMa and Zeta UMa.

 

I zoomed in for about 60x magnification to see the galaxy M81, visible only with averted vision.

 

I am left with two doubles of Olcott's list for UMa not observed: 57 UMa and STF 1561. They were already lost in the haze and in the city's light pollution. And I look forward with anticipation for a bit of armwrestling with BU 608 BC.

* I tested the Apex 28mm eyepiece, 2'' format, on the small Dobsonian. It provides a magnification of 31x and a real field on the sky of 1,8*: Cr 399 - almost completely fit in the field of the eyepiece, M29, M39, 61 Cyg, Zeta Lyr, Beta Lyr, star fields of the Milky Way. Not a great eyepiece but is usable at F/6.9. It was bonus so I will not throw it away.

* I concluded the session with a gift to ''heart, mind and soul''. That was a nice  split of Delta Cyg at 173x.

Mircea

Edited Monday at 17:19 by Mircea