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Splitting Doubles Stars


Mick H

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I split 52 and 32 Orionis with my Mewlon 210 a while back, though haven't tried recently due to the weather.

@Barry-W-Fenner anything beyond F needs some serious scopage and excellent seeing and likely excellent transparency too. Reference here to using a 36" dob with some of the beat observers there are out there. A challenge shall we say.

https://books.google.co.uk/books?id=fDQZAwAAQBAJ&pg=PA172&lpg=PA172&dq=barbara+texas+star+party+trapezium&source=bl&ots=IButERpdCI&sig=ACfU3U3-YCNiHEfffSmezDU-GEX39L28fw&hl=en&sa=X&ved=2ahUKEwi73ba4u6znAhWqgVwKHRjICCIQ6AEwCnoECAYQAQ#v=onepage&q=barbara texas star party trapezium&f=false

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Other interesting "point source" challenges include:

- spotting the central star in planetary nebulae. A few are relatively straightforward, many are rather difficult !

- spotting quasars. A few are possible with moderate aperture scopes and observing such distant objects is kind of fun.

- spotting supernovae when they occur. There is a bright one (relatively speaking) in NGC 4636 (Virgo) as I type.

- finding Barnards Star in Ophiuchus. The closest star (apart from the Sun) that we can see in the N. Hemisphere.

- spotting well known asteroids such as Ceres and 4 Vesta.

And many more ..... probably justifies a separate thread :smiley:

 

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7 hours ago, John said:

Other interesting "point source" challenges include:

- spotting the central star in planetary nebulae. A few are relatively straightforward, many are rather difficult !

- spotting quasars. A few are possible with moderate aperture scopes and observing such distant objects is kind of fun.

- spotting supernovae when they occur. There is a bright one (relatively speaking) in NGC 4636 (Virgo) as I type.

- finding Barnards Star in Ophiuchus. The closest star (apart from the Sun) that we can see in the N. Hemisphere.

- spotting well known asteroids such as Ceres and 4 Vesta.

And many more ..... probably justifies a separate thread :smiley:

 

Morning John,

As usual I have many questions regarding the above list (some daft, Some hopefully not so) I will look to start a thread as I would like to find out about finding these central stars and resolving Globular's

Regards

 

Baz

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22 minutes ago, Barry-W-Fenner said:

If I remember correctly there is a star on SkySafari which can be split into 3 bodies. Does anyone know of the top of there head which star this is? If not I can read through all start descriptions again.

 

Thank you

Baz

Iota Cassiopeia is a lovely triple star.

 

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  • 2 weeks later...
On 30/01/2020 at 18:47, Mick H said:

I would like to have a go at splitting doubles stars with my NexStar 8se, I have heard about it but never really tried it.

Have viewed at Albireo which i love. 

So my question is will the NexStar 8se be good for this, and if so any advise with splitting doubles stars.

 

On occasion, when I just want to coast along without giving much thought to anything in particular, I pick a constellation that's reasonably high and check out all the major constellation stars. To the naked eye they often appear as single points of light, but through the telescope they can be beautiful binaries which in many cases display contrasting colours. To make things a little more interesting, you can then look up information about the star using atlases etc. So in a sense, it's binary star observing in reverse. It's also easy to find yourself lured away from your primary target and start examining some truly exquisit pairs that you'd otherwise miss if your target was specific. Be warned though! You can lose all track of time very easily as minutes become hours.

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On 31/01/2020 at 00:44, John said:

Other interesting "point source" challenges include:

- spotting the central star in planetary nebulae. A few are relatively straightforward, many are rather difficult !

- spotting quasars. A few are possible with moderate aperture scopes and observing such distant objects is kind of fun.

- spotting supernovae when they occur. There is a bright one (relatively speaking) in NGC 4636 (Virgo) as I type.

- finding Barnards Star in Ophiuchus. The closest star (apart from the Sun) that we can see in the N. Hemisphere.

- spotting well known asteroids such as Ceres and 4 Vesta.

And many more ..... probably justifies a separate thread :smiley:

 

John, are there quasars, achievable for moderat apertures (e.g. 100mm)?

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On 31/01/2020 at 10:22, Stu said:

I split 52 and 32 Orionis with my Mewlon 210 a while back, though haven't tried recently due to the weather.

… and that's the challenge I'm setting myself tonight with the 12 inch Dob. Likewise our weather has been uncooperative of late but all bodes well this evening as the sun is sinking in a clear blue sky and the wind has dropped off. Very humid though, a bit tropical actually for us, so not sure if that will affect the seeing, especially for these two very tight doubles, time will tell.

I'm thinking around 230x to 250x will be needed, any advice for the best powers for splitting them gratefully accepted, though I think it'll be a case of suck it and see. :) 

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On 11/02/2020 at 08:47, Sergey said:

John, are there quasars, achievable for moderate apertures (e.g. 100mm)?

The brightest is 3C 273 in Virgo at magnitude 12.9. It depends how dark your skies are but while it might be theoretically possible with a 100mm aperture but practically 130mm would stand more of a chance.

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Well, mixed emotions really. Despite the warm sultry conditions the seeing was exceptional, rock steady and clear as a bell, so that was wonderful. The disappointment  (if you could call it that) was that splitting both 32 and 52 Orionis proved a bit too easy. I had geared myself up for a bit of a challenge and they both exposed themselves a little too readily. My goodness they're both jolly tight doubles though, if it weren't for the incredible seeing I think I would have struggled.

Started with my usual EP the Baader 8-24mm zoom up to 187x and moved up to the Morpheus 6.5mm for 230x. Could just about see the split with this but decided to go full bore with the SW Planetary 4mm for 375x and the splits were clear.

Followed this triumph with some slightly easier splits E &F in the Trapezium, very clear even with the 8mm zoom. Rigel B was too easy, but surprisingly Sirius Pup proved problematic, I eventually found it hiding directly behind one of the diffraction spikes, but once located I could see it even through the spike!

Put on the HB filter in the vain hope of spotting the Horsehead but no go, I don't think I'm going to see it with our skies here.

Nonetheless, had a bit of a grand tour of some old favorites our southern skies, Carina Nebula, Pearl Cluster, Southern Pleiades, Wishing Well Cluster, Tarantula Nebula.

If I only got one session as good as this a couple of times a year I think I would be content! :) 

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6 hours ago, John said:

The brightest is 3C 273 in Virgo at magnitude 12.9. It depends how dark your skies are but while it might be theoretically possible with a 100mm aperture but practically 130mm would stand more of a chance.

Would like to give that a go at some point, but that's just out of reach here with the Mewlon of 8" f8. Darker sky needed.

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6 hours ago, Geoff Barnes said:

Well, mixed emotions really. Despite the warm sultry conditions the seeing was exceptional, rock steady and clear as a bell, so that was wonderful. The disappointment  (if you could call it that) was that splitting both 32 and 52 Orionis proved a bit too easy. I had geared myself up for a bit of a challenge and they both exposed themselves a little too readily. My goodness they're both jolly tight doubles though, if it weren't for the incredible seeing I think I would have struggled.

Started with my usual EP the Baader 8-24mm zoom up to 187x and moved up to the Morpheus 6.5mm for 230x. Could just about see the split with this but decided to go full bore with the SW Planetary 4mm for 375x and the splits were clear.

Followed this triumph with some slightly easier splits E &F in the Trapezium, very clear even with the 8mm zoom. Rigel B was too easy, but surprisingly Sirius Pup proved problematic, I eventually found it hiding directly behind one of the diffraction spikes, but once located I could see it even through the spike!

Put on the HB filter in the vain hope of spotting the Horsehead but no go, I don't think I'm going to see it with our skies here.

Nonetheless, had a bit of a grand tour of some old favorites our southern skies, Carina Nebula, Pearl Cluster, Southern Pleiades, Wishing Well Cluster, Tarantula Nebula.

If I only got one session as good as this a couple of times a year I think I would be content! :) 

I guess the thing is Geoff, that what challenges us here in the UK may not trouble the southern observer. However other stuff we find mundane might be closer to the limit or beyond it for you because of that geography.

Saying that, a 1 arc second split is not an easy split normally, wherever you are :icon_biggrin:

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13 hours ago, John said:

The brightest is 3C 273 in Virgo at magnitude 12.9. It depends how dark your skies are but while it might be theoretically possible with a 100mm aperture but practically 130mm would stand more of a chance.

Thank you very much, John. I will try it.

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18 hours ago, Geoff Barnes said:

Well, mixed emotions really. Despite the warm sultry conditions the seeing was exceptional, rock steady and clear as a bell, so that was wonderful. The disappointment  (if you could call it that) was that splitting both 32 and 52 Orionis proved a bit too easy. I had geared myself up for a bit of a challenge and they both exposed themselves a little too readily. My goodness they're both jolly tight doubles though, if it weren't for the incredible seeing I think I would have struggled.

Started with my usual EP the Baader 8-24mm zoom up to 187x and moved up to the Morpheus 6.5mm for 230x. Could just about see the split with this but decided to go full bore with the SW Planetary 4mm for 375x and the splits were clear.

Followed this triumph with some slightly easier splits E &F in the Trapezium, very clear even with the 8mm zoom. Rigel B was too easy, but surprisingly Sirius Pup proved problematic, I eventually found it hiding directly behind one of the diffraction spikes, but once located I could see it even through the spike!

Put on the HB filter in the vain hope of spotting the Horsehead but no go, I don't think I'm going to see it with our skies here.

Nonetheless, had a bit of a grand tour of some old favorites our southern skies, Carina Nebula, Pearl Cluster, Southern Pleiades, Wishing Well Cluster, Tarantula Nebula.

If I only got one session as good as this a couple of times a year I think I would be content! :) 

Sounds great to me Geoff! So much bad seeing around it always seems amazingly easy when it finally stabilises. I got E & F through the Mewlon easily recently, whereas I often struggle with F. Purely down to seeing.

Last night I had a nice little session with a 4", and did manage 32 Orionis at high power (the scope took up to x300 very nicely). 52 was a bridge too far, I got elongation but no separation or even narrowing between the two. More power needed which I didn't have available.

Iota Cass looked stunning last night, I had forgotten just what a lovely triple that is.

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1 hour ago, Stu said:

Iota Cass looked stunning last night, I had forgotten just what a lovely triple that is.

Would love to be able to see that one Stu, but alas Cassiopeia never rises above the horizon here, just a smidgen below most of the year.

I wonder if most of the northern and southern skies are visible from the top of Kilimanjaro?

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4 hours ago, Stu said:

Iota Cass looked stunning last night, I had forgotten just what a lovely triple that is.

I have mainly used Cassiopeia for star hoping to the local clusters which near by. I really would like to see a triple so I will have to pay more attention to constellation Cassiopeia - Sky Safari here I come in search of this triple...

 

Baz

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4 minutes ago, Barry-W-Fenner said:

I have mainly used Cassiopeia for star hoping to the local clusters which near by. I really would like to see a triple so I will have to pay more attention to constellation Cassiopeia - Sky Safari here I come in search of this triple...

 

Baz

Quite an easy hop from Epsilon Cas. Telrad circles overlaid on it to show the scale.

Screenshot_20200214-105354_SkySafari 6 Pro.jpg

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Excellent thread. Skies cleared 90 minutes later then forecast last night, too late for any imaging or a proper session so plonked the 8" on the lawn and worked my way through the Orion list on page 1- getting as far as eta before the equipment and seeing stopped me. Really nice little session. Diffraction was causing me a few problems, and the aperture mask is too small for this sort of thing, but I found by holding my hand over half the aperture it greatly improved things. 

When there's a bit more time I'll definitely come back and have a go with better equipment 😊

 

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