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Pages: 1 | 2 | (show all) Dennis_S253 scholastic sledgehammer Reged: 11/22/11 Loc: West Central Florida eta cas question       #4986270 - 12/26/11 11:18 PM Edit   Reply   Quote Quick Reply   Seperation is listed at 12". When using stellarium I set up a test scope, a ETX 125. Using a 3.2 MM Ep which give close to 600X mag I can't see the split. Does stellarium not show double's correctly when using ocular view? Post Extras:       rookie Good Night Nurse Reged: 01/14/06 Loc: St. Petersburg, FL Re: eta cas question [Re: Dennis_S253]       #4986280 - 12/26/11 11:28 PM Edit   Reply   Quote Quick Reply   It's possible that your high power setting has made the field of view is too small to see both components. Try reducing the power and see what happens. Post Extras:       Dennis_S253 scholastic sledgehammer Reged: 11/22/11 Loc: West Central Florida Re: eta cas question [Re: rookie]       #4986686 - 12/27/11 09:59 AM Edit   Reply   Quote Quick Reply   At the close to 600x mag I can see a peanut shape. Upon doing some research... Simbad says eta cas is a Spectroscopic binary. Then doing some research on Spectroscopic binary, It says the 2 stars are so close that you can't split them with a telescope. There seems to be some confusion here. Post Extras:       Ziggy943 Post Laureate Reged: 08/11/06 Loc: Utah Re: eta cas question [Re: Dennis_S253]       #4986872 - 12/27/11 12:19 PM Edit   Reply   Quote Quick Reply   Eta Cass is an easy visual binary. At 600x you're way over magnifying. It would still easily fit into the FOV. Try it at about 100x and look for the deep magenta companion. The companion is a dwarf M0 star. You should not be having any trouble seeing this with a 5". Just be sure you're on the right star. Post Extras:       blb Post Laureate Reged: 11/25/05 Loc: Piedmont NC Re: eta cas question [Re: Dennis_S253]       #4986916 - 12/27/11 12:53 PM Edit   Reply   Quote Quick Reply   Quote: At the close to 600x mag I can see a peanut shape. Upon doing some research... Simbad says eta cas is a Spectroscopic binary. Then doing some research on Spectroscopic binary, It says the 2 stars are so close that you can't split them with a telescope. There seems to be some confusion here. What is the confusion? You can not see a spectroscopic binary without a spectroscope and the training to read the information. This is an easy visual pair at 12 seconds seperation. The fact that one of the stars is a spectroscopic binary and isn't visible with a telescope isn't a problem for me. Post Extras:       Dennis_S253 scholastic sledgehammer Reged: 11/22/11 Loc: West Central Florida Re: eta cas question [Re: blb]       #4987006 - 12/27/11 01:46 PM Edit   Reply   Quote Quick Reply   The fact that one of the stars is a spectroscopic binary and isn't visible with a telescope isn't a problem for me. So, if it isn't visible with a telescope, how can you split it? There must be another member of this system people are looking at and spliting. Post Extras:       blb Post Laureate Reged: 11/25/05 Loc: Piedmont NC Re: eta cas question [Re: Dennis_S253]       #4987041 - 12/27/11 02:12 PM Edit   Reply   Quote Quick Reply   Quote: So, if it isn't visible with a telescope, how can you split it? There must be another member of this system people are looking at and spliting. YES! that is correct. They are NOT looking at the spectroscopic pair, they can't. They are looking at the visual pair. The stat's in Sissy Haas's book, Double Stars for Small Telescopes has it listed this way; Magnitude: A=3.5, B=7.4 Seperation = 13.0" Position Angle = 319 degrees Year of Obs = 2003 These two stars can be seen with a small telescope as a showcase pair that are a striking yellow and ruddy-purple or garnet color. Just look at this pair with your telescope and not a computer screen and you will see. You failed to read beyond the first sentance in your quote. You did not read that I said: Quote: ...This is an easy visual pair at 12 seconds seperation. The fact that one of the stars is a spectroscopic binary and isn't visible with a telescope isn't a problem for me. Post Extras:       archer1960 sage Reged: 07/26/11 Re: eta cas question [Re: blb]       #4987154 - 12/27/11 03:38 PM Edit   Reply   Quote Quick Reply   Kind of like Rigel. It's easy to split A from B. Many people don't know that B is itself a spectoscopic binary, which cannot be split visually (AFAIK). Post Extras:       piyro member Reged: 05/14/10 Loc: Canary Islands, Spain Re: eta cas question [Re: blb]       #4987227 - 12/27/11 04:39 PM Edit   Reply   Quote Quick Reply   Quote: [...]The stat's in Sissy Haas's book, Double Stars for Small Telescopes has it listed this way; Magnitude: A=3.5, B=7.4 Seperation = 13.0" Position Angle = 319 degrees Year of Obs = 2003 These two stars can be seen with a small telescope as a showcase pair that are a striking yellow and ruddy-purple or garnet color. [...] Eta Cas is easy with my trash 60 mm f/12 refractor even an 35x. Not so easy with my 76 mm f/4 Celestron Firstscope. Pedro. Post Extras:       David Knisely Postmaster Reged: 04/19/04 Loc: southeastern Nebraska Re: eta cas question [Re: archer1960]       #4987298 - 12/27/11 05:40 PM Edit   Reply   Quote Quick Reply   Quote: Kind of like Rigel. It's easy to split A from B. Many people don't know that B is itself a spectoscopic binary, which cannot be split visually (AFAIK). It was the A component of Eta that was once thought to a spectroscopic binary, although after more detailed study (C.L. Morbey and R.F. Griffin, 1986), there is considerable doubt now that either star is one. Visually, they are quite an easy pair that are visible at 59x and look great at around 100x. The primary is an off-white color, while the companion is a dim reddish-orange hue (at least to my eyes using my 9.25 inch SCT) . Clear skies to you. Post Extras:       JIMZ7 Pooh-Bah Reged: 10/22/05 Loc: S.E.Michigan near DTW Re: eta cas question [Re: Dennis_S253]       #4987368 - 12/27/11 06:35 PM Edit   Reply   Quote Quick Reply   Are we talking about the same star? In a 4" f/9.8 refractor it splits easy at 42x but nicer at higher powers. Jim Post Extras:       Dennis_S253 scholastic sledgehammer Reged: 11/22/11 Loc: West Central Florida Re: eta cas question [Re: David Knisely]       #4987373 - 12/27/11 06:39 PM Edit   Reply   Quote Quick Reply   Thanks for the info guys. Last night I was out and thought I seen it at 80x and 103x. I was just confused about the way stellarium shows it not spliting. Post Extras:       David Knisely Postmaster Reged: 04/19/04 Loc: southeastern Nebraska Re: eta cas question [Re: Dennis_S253]       #4987939 - 12/28/11 03:02 AM Edit   Reply   Quote Quick Reply   Quote: Thanks for the info guys. Last night I was out and thought I seen it at 80x and 103x. I was just confused about the way stellarium shows it not spliting. Stellarium is basically "eye candy", and without a lot of modification often may not be all that useful as a rigorous tool for the die-hard amateur. Even Megastar doesn't show the companion to Eta-A, although when I switch the double star markers on, it does indicate that Eta is indeed a double, and when clicked on will show the WDS data on the double. Clear skies to you. Post Extras:       RLTYS Post Laureate Reged: 12/18/04 Loc: New York (Long Island) Re: eta cas question [Re: David Knisely]       #4987983 - 12/28/11 05:58 AM Edit   Reply   Quote Quick Reply   With my 10" refl using magnifications rangeing from 38-174x Eta appears, primary white, secondary org/yellow. Rich (RLTYS) Post Extras:       piyro member Reged: 05/14/10 Loc: Canary Islands, Spain Re: eta cas question [Re: RLTYS]       #4988696 - 12/28/11 03:47 PM Edit   Reply   Quote Quick Reply   Quote: With my 10" refl using magnifications rangeing from 38-174x Eta appears, primary white, secondary org/yellow. Rich (RLTYS) With my 60mm f/12 refractor at 56x it was easy, primary light yellow, secondary blue/white. Pedro. Post Extras:       David Knisely Postmaster Reged: 04/19/04 Loc: southeastern Nebraska Re: eta cas question [Re: piyro]       #4988914 - 12/28/11 06:06 PM Edit   Reply   Quote Quick Reply   Quote: Quote: With my 10" refl using magnifications rangeing from 38-174x Eta appears, primary white, secondary org/yellow. Rich (RLTYS) With my 60mm f/12 refractor at 56x it was easy, primary light yellow, secondary blue/white. Pedro. Well, in such a small scope, the color estimates might not be all that good. The primary is a brighter 3rd magnitude G0 V star which generally is an off-white or vague yellowish-white color, while the companion is a dim magnitude 7.5 K7 V class dwarf star that is definitely reddish-orange (color index 1.39) and not really blue at all. Clear skies to you. Post Extras:       Dennis_S253 scholastic sledgehammer Reged: 11/22/11 Loc: West Central Florida Re: eta cas question [Re: David Knisely]       #4989257 - 12/28/11 10:44 PM Edit   Reply   Quote Quick Reply   I thought I posted but I guess I didn't. Still need to learn this Quote stuff I quess. What I said was, tonight I was out and at 66.7X I could see a yellowish/white star and a orangish dimmer star. I opened up an old program I have called redshift 2. It says Eta Cas has (8) components. I can't believe I'm seeing Hip 3821A and Hip 3821B. Which makes me wonder why Sally list the A and B star Mags. I think I'm seeing a 8+ mag and there are a lot of other stars in the FOV. Post Extras:       David Knisely Postmaster Reged: 04/19/04 Loc: southeastern Nebraska Re: eta cas question [Re: Dennis_S253]       #4989405 - 12/29/11 01:19 AM Edit   Reply   Quote Quick Reply   Quote: I thought I posted but I guess I didn't. Still need to learn this Quote stuff I quess. What I said was, tonight I was out and at 66.7X I could see a yellowish/white star and a orangish dimmer star. I opened up an old program I have called redshift 2. It says Eta Cas has (8) components. I can't believe I'm seeing Hip 3821A and Hip 3821B. Which makes me wonder why Sally list the A and B star Mags. I think I'm seeing a 8+ mag and there are a lot of other stars in the FOV. Redshift was never known for its accuracy. There are at least seven stars brighter than 13th magnitude within about six arc minutes radius from Eta-A, but only one (Eta-B Cas) is a real physical companion (the rest are just fainter background stars). The nearest bright one other than Eta-B is 10th magnitude T 3663:1792:1 which sits about 1.7' arc to the southeast of Eta. Clear skies to you. Post Extras:       7331Peg Sirius Observer Reged: 09/01/08 Loc: North coast of Oregon Re: eta cas question [Re: Dennis_S253]       #4989432 - 12/29/11 01:53 AM Attachment (15 downloads) Edit   Reply   Quote Quick Reply   I covered this about a month ago, but I'll do it here again. The WDS lists ten components for Eta Cass, but as Dave says in the post following yours, only one (B) is known to be gravitationally linked. I came across the WDS listing by accident one evening, and was intrigued enough with the idea of seeing if I could hunt down all the components that I gave it a try. I located all of them without too much problem, and wrote up the whole affair here: Another Look at Eta Cassiopeiae, in which We Return in Search of All Ten Components And here's a sketch from that website showing the ten components: John Post Extras:       Asbytec Guy in a furry hat Reged: 08/08/07 Loc: La Union, PI Re: eta cas question [Re: 7331Peg]       #4989521 - 12/29/11 04:30 AM Edit   Reply   Quote Quick Reply   John, excellent observing report. I had fun attempting it and managed all but "J." Well, I think I glimpsed it in Stellarium. Post Extras:       Pages: 1 | 2 | (show all)

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