Re: [ap-gto] Re: [ap-ug] Sirius, Rigel, Castor


Apr 2, 2013

 


----------------------------

#64523 Apr 2, 2013

Yeap. It crosses the southern meridian around 01:30 AM.



Anthony.



???? 4/2/2013 23:19, ?/? chris1011@... ??????: >

>

> Where is Porrima now? Is it up this time of year?

>

> Rolando

>

> -----Original Message-----

> From: Anthony Ayiomamitis ayiomami@...

> mailto:ayiomami%40otenet.gr>>

> To: ap-ug ap-ug@yahoogroups.com mailto:ap-ug%40yahoogroups.com>>

> Cc: ap-gto ap-gto@yahoogroups.com mailto:ap-gto%40yahoogroups.com>>

> Sent: Tue, Apr 2, 2013 3:18 pm

> Subject: [ap-gto] Re: [ap-ug] Sirius, Rigel, Castor

>

> Rolando,

>

> Be careful with binary stars since they are an addictive preoccupation.

> It is something I used to pursue rather actively with my C14 and imaging

> them is fun as well when trying to get the right colours. If you would

> like a neat list with very helpful supplementary information such as

> separation and position angle, check the Astronomical League list at

> www.astroleague.org/al/obsclubs/dblstar/dblstar2.html .

>

> Nice work with these. How about Porrima next?

>

> Anthony.

>

> ???? 4/2/2013 22:49, ?/? chris1011@...

> mailto:chris1011%40aol.com> ??????:

> >

> >

> >

> > Hi All,

> >

> > Last night was clear and quite steady in the hour after sunset. I had

> > never seen the companion of Sirius before at my observatory, so I

> > swung the 8" EDF refractor into action, with 6mm and 4mm Zeiss Abbe

> > Ortho oculars.

> >

> > Just after sunset in the deepening twilight I saw the Pup sitting

> > quite nicely removed from the primary, visible about 80% of the time

> > as the skiy steadiness ebbed and flowed. Even though the star is only

> > about 30 degrees above the horizon here, myself and Howard both saw it

> > almost immediately, off to the right side. A quick look at the star

> > chart confirmed that it was indeed the Pup.

> >

> > What made it possible to see it visually was a little known accessory

> > that Valery Deryushin (Aries Optics) sent me some years back. This is

> > a special mirror diagonal with a variable prism that can be tuned to

> > exactly cancel out the atmospheric refraction, which is quite

> > noticeable at that low altitude.

> > In any case, I figured that if I could see it, I should be able to

> > image it. I put up my trusty STL11K camera and the very first shot at

> > 0.3 second exposure with a narrowband OIII filter showed the secondary

> > quite clearly. The attached image was taken with an H-a, OII and

> > normal Blue filter to achieve the RGB image. I also decided to image

> > Rigel, which has similar separation, and Castor, which is a closer

> double.

> >

> > All images were processed in MaximDL, 100 seperate sub-second

> > exposures of each color stacked. The images were then scaled up by a

> > factor of 4.17.

> >

> > Rolando

> >

> >

> www.astromart.com/common/image_popup.asp?image=/images/forums/803000-803999/803603.jpg&caption=

> >

> >

> www.astromart.com/common/image_popup.asp?image=/images/forums/803000-803999/803603.jpg&caption=>

> >

>







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