Jump to content


Sigma Orionis

This topic has been archived. This means that you cannot reply to this topic.
3 replies to this topic

#1 JayinUT


    I'm not Sleepy

  • *****
  • Posts: 3933
  • Joined: 19 Sep 2008

Posted 07 April 2009 - 11:01 PM

My next double that I looked at was Sigma Orionis.

"Both very young hydrogen-fusing dwarfs only a few million years old, the brighter is a magnificent blue class O (09.5) star, while the lesser is class B (B0.5). The pair orbit every 170 years at a distance of about 90 Astronomical Units. After correction for ultraviolet light from very hot (32,000 and 29,600 Kelvin) surfaces, they respectively radiate at a rate of 35,000 and 30,000 Suns. Temperature and luminosity give masses of 18 and 13.5 times that of the Sun, the sum of nearly 32 solar masses making the close AB pair among the most massive of visual binaries. Together they illuminate their surroundings, causing interstellar gas to glow."

This and more information can be found here.

Per my last post I used the XT8 and my 13mm and 5mm Stratus with the 2x shorty barlow. Seeing was 7/10 and transparency was 3/5. The image is based on a sketch done at the scope that night and is a digital scope made in Gimp.

Posted Image

#2 frank5817



  • *****
  • Posts: 8635
  • Joined: 13 Jun 2006

Posted 08 April 2009 - 01:23 PM


Simply beautiful. You do this very well. :cool: :rainbow: :bow:

Frank :)

#3 JayinUT


    I'm not Sleepy

  • *****
  • Posts: 3933
  • Joined: 19 Sep 2008

Posted 08 April 2009 - 02:08 PM

Thanks Frank. I'm learning. I'm thinking I should post the sketch at the scope. I was really happy with my sketch of M3 and am working on a digital version. Too much work though getting the new house ready to move in so it may be a week or so.

#4 CarlosEH


    Fly Me to the Moon

  • *****
  • Posts: 7339
  • Joined: 19 Jan 2005

Posted 09 April 2009 - 04:07 AM


An excellent observation of Sigma Orionis. This is a very interesting (and extremely brilliant!)double star in the heavens. Only Rigel (Beta Orionis) nearby is more luminous than this pair (40-66,000 Suns!, http://www.astro.ill.../sow/rigel.html ). Thank you for sharing it with us all.


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics