Back garden observing session 29.11.2017

[Doc]

Went out in the back garden last night. Managed four hours between 18.30 and 22.30. All of the double stars below were observed with the 12mm Clave' eyepiece. I'm really astounded by these Clave's, the 12mm is really sharp and shows pin point stars right to the edge. The 12mm Clave' gives a magnification of x70. I know they are not ortho's but they do act like such. Must get myself some of the smaller focal length ones.

 

Perseus

 

Epsilon Per - 2.91/8.88 - Easy - White/White

Eta Per - 3.75/8.50 - Easy - Yellow/White

Zeta Per - 2.88/9.16 - Easy - White/White

Theta Per - 4.11/10.25 - 20.4" - Hard and only glimpsed on and off - White/White

 

Aries

 

Gamma Ari - 3.88/4.58 - 7.5" - Medium - White/White

41 Ari - 3.61/11.04 - 34" - Hard only glimpse it occasionally as it's 11.04 mag and on the limit of the scope - White/White

Auriga

 

Theta Aur - 2.65/7.20 - 4" - Hard - White/White

 

Cepheus

 

Beta Cep - 3.23/8.63 - 14.8" - Easy - White/White

Garnet Star - 4.01 - Couldn't detect any of the companions - Red

Xi Cep - 4.40/6.40 - 8.4" - Medium - White/White

 

Gemini

 

Alpha Gem (Castor) - 1.58/2.97 - 5.3" - Medium - White/White

77 Gem - 3.56/8.20 - 7.9" - Hard - Whte/White

Eta Gem - 3.29/6.15 - 1.6" - Only managed a peanut split even with the 6mm Delos

Epsilon Gem - 3.00/9.64 - 110" - Very Easy - White/White

Delta Gem - 3.53/8.18 - 5.5" - Easy - White/White

Zeta Gem - 4.07/10.70 - 87.4" - Easy

 

Ursa Major

 

23 UMa - 3.65/9.18 - 23.2" - Easy - White/White

Iota UMa - 3.14/9.20 - 1.9" - Only managed a peanut split

 

Orion

 

Lambda Ori - 3.51/5.45/10.72 - 4.9"/28.7" - All three stars split

Zeta Ori - 1.9/3.7/9.6 - 2.3"/58" - Medium - All three stars split

Epsilon Ori - 1.72/10.5 - 179" - Easy

Beta Ori (Rigel) - 0.28/6.80 - 9.3" - Easy - White/White

Tau Ori - 3.59/11.00 - 33.3" - Hard - Only glimpsed with averted vision

Eta Ori - 3.39/4.87 - 1.8" - Only managed a peanut split.

31 Ori - 4.69/9.70 - 12.7" - Medium - Secondary looked very dim, I would say dimmer then 9.70 mag

Iota Ori - 2.9/7.0/9.7 - 10.8"/49.4" - All three seen - Easy

 

 

 

 

[Stu]

Great session Doc. I'll certainly try for some of these if it stays clear tonight.

[cotterless45]

Superb report, Bogardus is always a challenge. Iota Orionis is a great view in NGC 1980, good to have results under a waxing Moon, Nick.

[chiltonstar]

A very nice report! I'm intrigued by one observation - Iota Ori which you describe as a triple. Visually this is said in CDSA to be two components, with Struve 745 and 747 nearby??

Chris

[Doc]

7 hours ago, chiltonstar said:

A very nice report! I'm intrigued by one observation - Iota Ori which you describe as a triple. Visually this is said in CDSA to be two components, with Struve 745 and 747 nearby??

Chris

My info was mainly Steve O'Meara books Hidden Treasures and Herschel 400 Observing guide, he calls Iota Orionis (STF752) a triple star. Also in Burnhams Celestrial Handbook Iota Orionis is also called a triple star. 

[chiltonstar]

14 minutes ago, Doc said:

My info was mainly Steve O'Meara books Hidden Treasures and Herschel 400 Observing guide, he calls Iota Orionis (STF752) a triple star. Also in Burnhams Celestrial Handbook Iota Orionis is also called a triple star. 

Interesting differences in the information, I tend to use WDS/Stelle Doppie to be sure, and CDSA will only include stars genuinely part of the system, not ones that are optical doubles.

Chris

[Stu]

SkySafari describes it as a quadruple system. The primary as a spectroscopic binary, and then a 7th mag companion at 11" and an 11th mag one at 50", both with listed orbital periods implying they are a system.

Strangely though it does not show the 11th mag component, just the 7th.

[chiltonstar]

47 minutes ago, Stu said:

SkySafari describes it as a quadruple system. The primary as a spectroscopic binary, and then a 7th mag companion at 11" and an 11th mag one at 50", both with listed orbital periods implying they are a system.

Strangely though it does not show the 11th mag component, just the 7th.

Certainly some odd discrepancies in these listings. Even for a star as well known as Sigma Orionis, many observers and sources don't quote the C component which is pretty obvious for scopes of 100mm or more.

Chris

[Stu]

3 hours ago, chiltonstar said:

Certainly some odd discrepancies in these listings. Even for a star as well known as Sigma Orionis, many observers and sources don't quote the C component which is pretty obvious for scopes of 100mm or more.

Chris

Indeed. For Sigma Orionis SkySafari acknowledges the C component in the description and the separation data but doesn't actually show it!

[Paul73]

Sky Safari lists 9 components down to mag 12.1 for Sigma Orionis despite referring to is as a Quintuple system! Consistency must be very very hard with that much data.

Paul

[chiltonstar]

3 hours ago, Paul73 said:

Sky Safari lists 9 components down to mag 12.1 for Sigma Orionis despite referring to is as a Quintuple system! Consistency must be very very hard with that much data.

Paul

That makes a certain sense though: CDSA gives it as a septuple (7) system, with 5 visible components (A has three inseparable components - spectroscopic). There are other unrelated components in the same group.

Chris